From 608370c630b6fdd4ed5fbbc956eb817fbc8ff271 Mon Sep 17 00:00:00 2001
From: atraversatlassian <141701698+atraversatlassian@users.noreply.github.com>
Date: Fri, 15 Sep 2023 10:47:46 +1000
Subject: [PATCH] NONE Enabling more eslint rules and fixing errors (#2413)

* NONE Enabling more eslint rules and fixing errors

* NONE fix unit tests

* NONE fix more unit tests

* NONE fix lint errors from merge

* Clean up jest expect rule

* NONE refactor eslint file

* Fix lint errors from merge

* Addressing initial feedback

* Addressing feedback

* More careful with toString

* Address feedback

* Addressing feedback

* minor fixes

* Fix some typing
---
 .eslintrc.json                                | 100 +++++++++++-------
 package.json                                  |   1 +
 src/app.test.ts                               |   4 +-
 src/app.ts                                    |   2 +-
 src/config/jira-test-site-check.test.ts       |   2 +-
 src/config/logger.ts                          |   6 +-
 src/config/metric-helpers.test.ts             |   2 +-
 src/config/statsd.ts                          |   2 +-
 src/github/client/app-token-holder.ts         |   2 +-
 src/github/client/github-anonymous-client.ts  |   2 +-
 src/github/client/github-client-errors.ts     |   2 +-
 .../client/github-client-interceptors.ts      |   2 +-
 src/github/client/github-client.ts            |   4 +-
 src/github/client/github-client.types.ts      |  22 ++++
 src/github/client/github-queries.ts           |   1 +
 src/github/code-scanning-alert.test.ts        |  63 ++++++++++-
 src/github/code-scanning-alert.ts             |   9 +-
 src/github/installation.ts                    |   2 +-
 src/github/issue-comment.ts                   |   9 +-
 src/github/repository.ts                      |   2 +-
 src/jira/client/jira-client.ts                |   6 +-
 src/jira/util/jira-client-util.ts             |   3 +-
 src/jira/util/jwt.test.ts                     |   6 +-
 src/jira/util/jwt.ts                          |  27 ++---
 src/middleware/github-webhook-middleware.ts   |   6 +-
 .../jira-symmetric-jwt-middleware.ts          |   9 +-
 src/models/axios-error-event-decorator.ts     |   2 +-
 src/models/encrypted-model.test.ts            |   2 +-
 src/models/installation.test.ts               |   4 +-
 .../jira-admin/jira-admin-check.test.ts       |   2 +-
 src/rest/routes/analytics-proxy/index.test.ts |   2 +-
 src/rest/routes/github-apps/index.test.ts     |   2 +-
 src/rest/routes/github-orgs/index.test.ts     |   2 +-
 src/rest/routes/jira/index.test.ts            |   2 +-
 src/rest/routes/oauth/index.test.ts           |   2 +-
 src/routes/api/api-router.ts                  |   2 +-
 .../api/client-key/recover-client-key.ts      |   2 +-
 ...t-failed-and-pending-deployment-cursors.ts |   2 +-
 .../data-cleanup/cleanup-reposyncstates.ts    |   4 +-
 .../api/db-migrations/db-migration-down.ts    |   2 +-
 .../api/db-migrations/db-migration-utils.ts   |   6 +-
 .../api/installation/api-installation-get.ts  |   5 +-
 .../api/jira/api-jira-uninstall-post.ts       |   2 +-
 .../github-configuration-app-installs-get.ts  |   2 +-
 .../configuration/github-configuration-get.ts |  12 ++-
 .../create-branch/github-branches-get.test.ts |   2 +-
 .../github-create-branch-get.test.ts          |   6 +-
 .../create-branch/github-create-branch-get.ts |   6 +-
 .../github-create-branch-options-get.ts       |   4 +-
 ...github-create-branch-post.frontend.test.ts |   4 +-
 .../github-create-branch-post.ts              |   3 +-
 src/routes/github/github-5ku-router.ts        |   4 +-
 src/routes/github/github-oauth.ts             |   3 +-
 src/routes/github/github-router.test.ts       |   2 +-
 .../manifest/github-manifest-complete-get.ts  |   2 +-
 src/routes/github/setup/github-setup-post.ts  |   2 +-
 ...ithub-subscription-deferred-install-get.ts |   2 +-
 ...thub-subscription-deferred-install-post.ts |   2 +-
 .../github/webhook/webhook-receiver-post.ts   |   5 +-
 .../jira-atlassian-connect-get.ts             |   2 +-
 ...nnect-enterprise-app-create-or-edit-get.ts |   5 +-
 .../jira-connect-enterprise-app-post.test.ts  |   8 +-
 .../app/jira-connect-enterprise-app-put.ts    |   5 +-
 .../app/jira-connect-enterprise-apps-get.ts   |   5 +-
 .../jira-connect-enterprise-delete.ts         |   5 +-
 .../enterprise/jira-connect-enterprise-get.ts |   5 +-
 .../jira-connect-enterprise-post.ts           |  12 +--
 src/routes/jira/connect/jira-connect-get.ts   |   5 +-
 .../jira/jira-connected-repos-get.test.ts     |   2 +-
 src/routes/jira/jira-connected-repos-get.ts   |   5 +-
 src/routes/jira/jira-delete.test.ts           |   4 +-
 src/routes/jira/jira-get.ts                   |   7 +-
 .../jira-security-workspaces-post.test.ts     |  12 +--
 src/routes/version/version-get.ts             |   4 +-
 .../subscription-installation-service.test.ts |   4 +-
 src/sqs/backfill-error-handler.test.ts        |   2 +-
 src/sqs/error-handlers.ts                     |  13 +--
 src/sqs/sqs.ts                                |   4 +-
 src/sync/branches.ts                          |   3 +-
 src/sync/code-scanning-alerts.ts              |   4 +-
 src/sync/commits.ts                           |   3 +-
 src/sync/deduplicator.test.ts                 |   2 +-
 src/sync/dependabot-alerts.ts                 |   4 +-
 src/sync/deployment.test.ts                   |  29 +++--
 src/sync/installation.test.ts                 |   2 +-
 src/sync/parallel-page-fetcher.test.ts        |  20 ++--
 src/sync/scheduler.test.ts                    |  10 +-
 src/sync/transforms/branch.ts                 |   6 +-
 src/transforms/push.ts                        |   2 +-
 .../transform-code-scanning-alert.ts          |  10 +-
 src/transforms/transform-dependabot-alert.ts  |   4 +-
 src/transforms/transform-deployment.test.ts   |   8 +-
 src/transforms/transform-pull-request.ts      |   2 +-
 src/transforms/transform-repository-id.ts     |   2 +-
 .../transform-secret-scanning-alert.ts        |   2 +-
 src/transforms/transform-workflow.ts          |   2 +-
 src/util/create-url-with-query-string.ts      |   3 +-
 src/util/curl/curl-utils.test.ts              |   4 +-
 src/util/error-string-from-unknown.ts         |   3 +
 src/util/handlebars/handlebar-helpers.ts      |   4 +-
 src/util/jira-utils.test.ts                   |   2 +-
 src/util/logger-utils.ts                      |   2 +-
 src/util/workers-health-monitor.ts            |   8 +-
 test/e2e/utils/jira.ts                        |   2 +-
 .../setup/matchers/to-be-called-with-delay.ts |   2 +-
 test/setup/matchers/to-promise.ts             |   2 +-
 test/setup/setup.ts                           |   2 +-
 .../routes/api/api-router.test.ts.snap        |   2 +-
 test/snapshots/snapshot-resolver.ts           |   2 +-
 test/utils/database-state-creator.ts          |   2 +-
 yarn.lock                                     |   5 +
 111 files changed, 399 insertions(+), 272 deletions(-)
 create mode 100644 src/util/error-string-from-unknown.ts

diff --git a/.eslintrc.json b/.eslintrc.json
index c8e9580a6e..dae25f8aec 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -35,11 +35,12 @@
 		}
 	},
 	"rules": {
-		"@typescript-eslint/explicit-module-boundary-types": "off",
-		"@typescript-eslint/no-var-requires": "error",
-		"@typescript-eslint/no-unused-vars": ["error", { "argsIgnorePattern": "^_" }],
-		"no-unused-vars": "off",
-		"no-console": "error",
+		"indent": ["error", "tab", {
+			"SwitchCase": 1
+		}],
+		"@typescript-eslint/indent": ["error", "tab", {
+			"SwitchCase": 1
+		}],
 		"quotes": [
 			"error",
 			"double",
@@ -48,13 +49,7 @@
 				"allowTemplateLiterals": true
 			}
 		],
-		"indent": ["error", "tab", {
-			"SwitchCase": 1
-		}],
-		"@typescript-eslint/indent": ["error", "tab", {
-			"SwitchCase": 1
-		}],
-		"@import/no-unresolved": "off",
+		//extra rules
 		"object-curly-spacing": ["error", "always"],
 		"semi": ["error", "always"],
 		"no-trailing-spaces": "error",
@@ -62,34 +57,17 @@
 		"keyword-spacing": "error",
 		"space-in-parens": ["error", "never"],
 		"func-style" : ["error", "expression"],
-		"require-await": "off",
 		"@typescript-eslint/no-floating-promises": ["error"],
-		"jest/expect-expect": [
-			"error",
-			{
-				"assertFunctionNames": [
-					"expect",
-					"supertest.**.expect",
-					"*.expect"
-				]
-			}
-		],
-		// To be removed later
-		"@typescript-eslint/no-non-null-assertion": "off",
-		"@typescript-eslint/no-explicit-any": "off",
-		"@typescript-eslint/prefer-nullish-coalescing": "off",
-		"@typescript-eslint/restrict-template-expressions": "off",
-		"@typescript-eslint/no-unsafe-assignment": "off",
-		"@typescript-eslint/no-unsafe-argument": "off",
-		"@typescript-eslint/no-unsafe-member-access": "off",
-		"@typescript-eslint/no-unsafe-return": "off",
-		"@typescript-eslint/no-unsafe-call": "off",
-		"@typescript-eslint/unbound-method": "off",
-		"@typescript-eslint/require-await": "off",
-		"@typescript-eslint/await-thenable": "off",
-		"@typescript-eslint/restrict-plus-operands": "off",
-		"@typescript-eslint/no-misused-promises": "off"
-		
+		"@typescript-eslint/explicit-module-boundary-types": "off",
+		"@typescript-eslint/no-var-requires": "error",
+		"@typescript-eslint/no-unused-vars": ["error", { "argsIgnorePattern": "^_" }],
+		"no-unused-vars": ["error", { "argsIgnorePattern": "^_" }],
+		"no-console": "error",
+		"@typescript-eslint/restrict-template-expressions": ["error", {
+			"allowBoolean": true,
+			"allowNullish": true,
+			"allowNumber": true
+		}]
 	},
 	"overrides": [{
 		"files": [ "test/**/*.ts", "src/**/*.test.ts" ],
@@ -100,7 +78,49 @@
 			"@typescript-eslint/no-explicit-any": "off",
 			"@typescript-eslint/no-non-null-assertion": "off",
 			"jest/no-done-callback": "off",
-			"jest/expect-expect": "off"
+			"jest/expect-expect": [
+				"error",
+				{
+					"assertFunctionNames": [
+						"expect",
+						"supertest.**.expect",
+						"*.expect",
+						"expectDisabledButton",
+						"expectEnabledButton"
+					]
+				}
+			]
+		}
+	},
+	{
+		"files": [ 
+			"test/**",
+			"src/*.ts",
+			"src/config/**",
+			"src/github/**",
+			"src/jira/**",
+			"src/middleware/**",
+			"src/models/**",
+			"src/rest/**",
+			"src/routes/**",
+			"src/services/**",
+			"src/sqs/**",
+			"src/sync/**",
+			"src/transforms/**",
+			"src/util/**",
+			"src/worker/**"
+		],
+		"rules": {
+			// To be removed later
+			"@typescript-eslint/no-unsafe-assignment": "off",
+			"@typescript-eslint/no-unsafe-argument": "off",
+			"@typescript-eslint/no-unsafe-member-access": "off",
+			"@typescript-eslint/no-unsafe-return": "off",
+			"@typescript-eslint/no-unsafe-call": "off",
+			"@typescript-eslint/unbound-method": "off",
+			"@typescript-eslint/require-await": "off",
+			"@typescript-eslint/await-thenable": "off",
+			"@typescript-eslint/no-misused-promises": "off"
 		}
 	}]
 }
diff --git a/package.json b/package.json
index 1f41798766..e1ae61f755 100644
--- a/package.json
+++ b/package.json
@@ -63,6 +63,7 @@
 		"@octokit/auth-app": "^2.6.0",
 		"@octokit/graphql-schema": "^10.73.0",
 		"@sentry/node": "^6.8.0",
+		"@types/safe-json-stringify": "^1.1.2",
 		"atlassian-jwt": "^2.0.0",
 		"aws-sdk": "^2.1015.0",
 		"axios": "^0.26.0",
diff --git a/src/app.test.ts b/src/app.test.ts
index 7a6488f9d2..3d74e7c183 100644
--- a/src/app.test.ts
+++ b/src/app.test.ts
@@ -6,7 +6,7 @@ describe("app", () => {
 		it("please review routes and update snapshot when adding or modifying the routes!", async () => {
 			const app = getFrontendApp();
 
-			const appRoutes: Array<any> = [];
+			const appRoutes: Array<{method: string, path: string, exec: string[]}> = [];
 			const collectRoutes = (stack, parentPath = "", parentMiddlewares: Array<any> = []) => {
 				const ROOT_REGEX = parentPath + sanitizeRegexStr("^\\/?(?=\\/|$)");
 				const pathMiddlewares = {};
@@ -51,7 +51,7 @@ describe("app", () => {
 			collectRoutes(app._router.stack);
 
 			const allRoutes = appRoutes.map(route =>
-				":" + route.method.toUpperCase() + " " + route.path + "\n\t" + route.exec.join(",")
+				`:${route.method.toUpperCase()} ${route.path}\n\t${route.exec.join(",")}`
 			).join("\n");
 
 			expect(allRoutes).toMatchSnapshot();
diff --git a/src/app.ts b/src/app.ts
index 3019eaadf6..b3e62a4ab1 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -44,7 +44,7 @@ const secureHeaders = (app: Express) => {
 			defaultSrc: ["'self'"],
 			// Allow <script> tags hosted by ourselves and from atlassian when inserted into an iframe
 			scriptSrc: ["'self'", process.env.APP_URL, "https://*.atlassian.net", "https://*.jira.com", "https://connect-cdn.atl-paas.net/",
-				"'unsafe-inline'", "'strict-dynamic'", (_: Request, res: Response): string => `'nonce-${res.locals.nonce}'`],
+				"'unsafe-inline'", "'strict-dynamic'", (_: Request, res: Response): string => `'nonce-${res.locals.nonce as string}'`],
 			// Allow XMLHttpRequest/fetch requests
 			connectSrc: ["'self'", process.env.APP_URL],
 			// Allow <style> tags hosted by ourselves as well as style="" attributes
diff --git a/src/config/jira-test-site-check.test.ts b/src/config/jira-test-site-check.test.ts
index 946a0a8830..d7107621c0 100644
--- a/src/config/jira-test-site-check.test.ts
+++ b/src/config/jira-test-site-check.test.ts
@@ -7,7 +7,7 @@ describe.each([
 	["https://site-3.some-test.atlassian.net", true],
 	["https://real-site-1.non-test.atlassian.net", false]
 ])("Checking whether it is jira test site", (site, shouldBeTest) => {
-	it(`should successfully check ${site} to be is-jira-test-site?: ${shouldBeTest}`, () => {
+	it(`should successfully check ${site ?? "undefined"} to be is-jira-test-site?: ${shouldBeTest}`, () => {
 		expect(isTestJiraHost(site)).toBe(shouldBeTest);
 	});
 });
diff --git a/src/config/logger.ts b/src/config/logger.ts
index 17a36ef71b..832a047e4d 100644
--- a/src/config/logger.ts
+++ b/src/config/logger.ts
@@ -40,7 +40,7 @@ const GIT_REF_URL_REGEX = /^(.*)\/git\/ref\/([^/]+)$/;
 const isGitRefUrl = (url: string) => url.match(GIT_REF_URL_REGEX);
 
 const removeGitRefFromUrl = (url: string) =>
-	url.replace(GIT_REF_URL_REGEX, (_, prefix, gitRef) =>
+	url.replace(GIT_REF_URL_REGEX, (_, prefix: string, gitRef) =>
 		`${prefix}/git/ref/${createHashWithSharedSecret(decodeURIComponent(gitRef))}`
 	);
 
@@ -62,7 +62,7 @@ const REST_DEVINFO_BRANCH_URL_REGEX = /^\/rest\/devinfo\/([^/]+)\/repository\/([
 const isDevInfoBranchUrl = (url: string) => url.match(REST_DEVINFO_BRANCH_URL_REGEX);
 
 const removeBranchFromDevInfoUrl = (url: string) =>
-	url.replace(REST_DEVINFO_BRANCH_URL_REGEX, (_, version, repoNo, branchaName, updateSequenceId) =>
+	url.replace(REST_DEVINFO_BRANCH_URL_REGEX, (_, version, repoNo, branchaName, updateSequenceId: string) =>
 		[
 			"/rest/devinfo",
 			version,
@@ -101,7 +101,7 @@ const removeOwnersAndReposFromUrl = (url: string) =>
 			"repos",
 			createHashWithSharedSecret(decodeURIComponent(repos)),
 			"branches"
-		].join("/") + suffix
+		].join("/") + (suffix as string)
 	);
 
 const censorUrl = (url) => {
diff --git a/src/config/metric-helpers.test.ts b/src/config/metric-helpers.test.ts
index 000dc29fed..3ef1112404 100644
--- a/src/config/metric-helpers.test.ts
+++ b/src/config/metric-helpers.test.ts
@@ -11,7 +11,7 @@ describe("metrics helper", () => {
 		{ repoNum: 1000, bucket: "1000+" },
 		{ repoNum: 10000, bucket: "1000+" }
 	])("for each repo num", ({ repoNum, bucket }) => {
-		it(`should show correct bucket ${bucket} for repo num ${repoNum}`, () => {
+		it(`should show correct bucket ${bucket} for repo num ${repoNum || "undefined"}`, () => {
 			expect(repoCountToBucket(repoNum)).toEqual(bucket);
 		});
 	});
diff --git a/src/config/statsd.ts b/src/config/statsd.ts
index a27942e080..f3e1e55346 100644
--- a/src/config/statsd.ts
+++ b/src/config/statsd.ts
@@ -103,7 +103,7 @@ export const elapsedTimeMetrics = (
 	res.once("finish", () => {
 		const elapsedTime = elapsedTimeInMs();
 		const statusCode = `${res.statusCode}`;
-		const path = (req.baseUrl || "") + (req.route?.path || "/*");
+		const path = (req.baseUrl || "") + (req.route?.path as string || "/*");
 		const tags = { path, method, statusCode };
 		(req.log || logger).debug(`${method} request executed in ${elapsedTime} with status ${statusCode} path ${path}`);
 
diff --git a/src/github/client/app-token-holder.ts b/src/github/client/app-token-holder.ts
index 5d54d7d4eb..77f2c95cad 100644
--- a/src/github/client/app-token-holder.ts
+++ b/src/github/client/app-token-holder.ts
@@ -58,7 +58,7 @@ export class AppTokenHolder {
 		if (!currentToken || currentToken.isAboutToExpire()) {
 			const key = await keyLocator(ghsaId, jiraHost);
 			if (!key) {
-				throw new Error(`No private key found for GitHub app ${appId.toString}`);
+				throw new Error(`No private key found for GitHub app ${appId.toString()}`);
 			}
 			currentToken = AppTokenHolder.createAppJwt(key, appId.appId.toString());
 			this.appTokenCache.set(appId.toString(), currentToken);
diff --git a/src/github/client/github-anonymous-client.ts b/src/github/client/github-anonymous-client.ts
index f0e00b6ccc..70990b5235 100644
--- a/src/github/client/github-anonymous-client.ts
+++ b/src/github/client/github-anonymous-client.ts
@@ -86,7 +86,7 @@ export class GitHubAnonymousClient extends GitHubClient {
 		// In case of invalid or expired refresh token, GitHub API returns status code 200 with res.data object contains error fields,
 		// so adding check for presence of access token to make sure that new access token has been generated.
 		if (!res.data?.access_token) {
-			throw new Error(`Failed to renew access token ${res.data?.error}`);
+			throw new Error(`Failed to renew access token ${res.data?.error as string}`);
 		}
 		return {
 			accessToken: res.data.access_token,
diff --git a/src/github/client/github-client-errors.ts b/src/github/client/github-client-errors.ts
index d5f12052ff..b3858396d8 100644
--- a/src/github/client/github-client-errors.ts
+++ b/src/github/client/github-client-errors.ts
@@ -17,7 +17,7 @@ export class GithubClientError extends Error {
 		this.uiErrorCode = "UNKNOWN";
 
 		this.cause = { ...cause };
-		this.stack = this.stack?.split("\n").slice(0, 2).join("\n") + "\n" + cause.stack;
+		this.stack = (this.stack?.split("\n").slice(0, 2).join("\n") ?? "Missing Stack") + "\n" + (cause.stack ?? "Missing Stack");
 	}
 }
 
diff --git a/src/github/client/github-client-interceptors.ts b/src/github/client/github-client-interceptors.ts
index 803fa85528..e5623e43fb 100644
--- a/src/github/client/github-client-interceptors.ts
+++ b/src/github/client/github-client-interceptors.ts
@@ -43,7 +43,7 @@ export const setRequestTimeout = async (config: AxiosRequestConfig): Promise<Axi
 //TODO Move to util/axios/common-github-webhook-middleware.ts and use with Jira Client
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 const sendResponseMetrics = (metricName: string, gitHubProduct: string, jiraHost: string | undefined, response?: any, status?: string | number, extraTags?: Record<string, string | undefined>) => {
-	status = `${status || response?.status}`;
+	status = `${status?.toString() || response?.status as string}`;
 	const requestDurationMs = Number(
 		Date.now() - (response?.config?.requestStartTime || 0)
 	);
diff --git a/src/github/client/github-client.ts b/src/github/client/github-client.ts
index 167a78ddb4..f2a5d5ae19 100644
--- a/src/github/client/github-client.ts
+++ b/src/github/client/github-client.ts
@@ -127,11 +127,11 @@ export class GitHubClient {
 		);
 		this.axios.interceptors.response.use(
 			instrumentRequest(metricHttpRequest.github, this.restApiUrl, jiraHost, {
-				withApiKey: "" + (!!gitHubConfig.apiKeyConfig),
+				withApiKey: (!!gitHubConfig.apiKeyConfig).toString(),
 				...this.metrics
 			}),
 			instrumentFailedRequest(metricHttpRequest.github, this.restApiUrl, jiraHost, {
-				withApiKey: "" + (!!gitHubConfig.apiKeyConfig),
+				withApiKey: (!!gitHubConfig.apiKeyConfig).toString(),
 				...this.metrics
 			})
 		);
diff --git a/src/github/client/github-client.types.ts b/src/github/client/github-client.types.ts
index 560711dd73..ddb187ea8c 100644
--- a/src/github/client/github-client.types.ts
+++ b/src/github/client/github-client.types.ts
@@ -144,6 +144,28 @@ export type CodeScanningAlertResponseItem = {
 	most_recent_instance: CodeScanningAlertResponseItemMostRecentInstance;
 };
 
+export interface Branch {
+	associatedPullRequests: {
+		nodes: {
+			title: string;
+		}[];
+	};
+	name: string;
+	target: {
+		author: {
+			avatarUrl: string;
+			email: string;
+			name: string;
+		};
+		authoredDate: string;
+		changedFiles: number;
+		oid: string;
+		message: string;
+		url: string;
+		history: any;
+	};
+}
+
 type CodeScanningAlertResponseItemRule = {
 	name: string;
 	description: string;
diff --git a/src/github/client/github-queries.ts b/src/github/client/github-queries.ts
index 32332a6afe..16b24ac993 100644
--- a/src/github/client/github-queries.ts
+++ b/src/github/client/github-queries.ts
@@ -534,6 +534,7 @@ export type DeploymentQueryNode = {
 	cursor: string,
 	node: {
 		createdAt: string,
+		updatedAt?: string,
 		repository: Repository,
 		databaseId: string,
 		commitOid: string,
diff --git a/src/github/code-scanning-alert.test.ts b/src/github/code-scanning-alert.test.ts
index 81e7156342..4d48c956a2 100644
--- a/src/github/code-scanning-alert.test.ts
+++ b/src/github/code-scanning-alert.test.ts
@@ -10,6 +10,8 @@ import { mocked } from "jest-mock";
 import { emitWebhookProcessedMetrics } from "utils/webhook-utils";
 import Logger from "bunyan";
 import { booleanFlag } from "config/feature-flags";
+import { JiraClient } from "../jira/client/jira-client";
+
 jest.mock("config/feature-flags");
 jest.mock("utils/webhook-utils");
 jest.mock("../transforms/transform-code-scanning-alert");
@@ -44,6 +46,57 @@ const getWebhookContext = <T>(): WebhookContext<T> => {
 	};
 };
 
+const createMockJiraClient = () : JiraClient => {
+	return {
+		baseURL: JIRA_BASE_URL,
+		remoteLink: {
+			submit: jest.fn()
+		},
+		security: {
+			submitVulnerabilities: jest.fn()
+		},
+		issues: {
+			get: jest.fn(),
+			getAll: jest.fn(),
+			parse: jest.fn(),
+			comments: {
+				list: jest.fn(),
+				addForIssue: jest.fn(),
+				updateForIssue: jest.fn(),
+				deleteForIssue: jest.fn()
+			},
+			transitions: {
+				getForIssue: jest.fn(),
+				updateForIssue: jest.fn()
+			},
+			worklogs: {
+				addForIssue: jest.fn()
+			}
+		},
+		devinfo: {
+			branch: {
+				delete: jest.fn()
+			},
+			installation: {
+				delete: jest.fn()
+			},
+			pullRequest: {
+				delete: jest.fn()
+			},
+			repository: {
+				delete: jest.fn(),
+				update: jest.fn()
+			}
+		},
+		workflow: {
+			submit: jest.fn()
+		},
+		deployment: {
+			submit: jest.fn()
+		}
+	};
+};
+
 describe("Code Scanning Alert Webhook Handler", () => {
 	beforeEach(() => {
 		jest.resetAllMocks();
@@ -52,11 +105,11 @@ describe("Code Scanning Alert Webhook Handler", () => {
 
 	const mockJiraRemoteLinkSubmit = jest.fn();
 	const mockJiraSecuritySubmit = jest.fn();
-	const jiraClient = {
-		baseURL: JIRA_BASE_URL,
-		remoteLink: { submit: mockJiraRemoteLinkSubmit },
-		security: { submitVulnerabilities: mockJiraSecuritySubmit }
-	};
+	const jiraClient = createMockJiraClient();
+
+	jiraClient.baseURL = JIRA_BASE_URL;
+	jiraClient.remoteLink.submit = mockJiraRemoteLinkSubmit;
+	jiraClient.security.submitVulnerabilities = mockJiraSecuritySubmit;
 
 	it("transform and submit remote link to jira", async () => {
 		const jiraPayload = { remoteLinks: [] };
diff --git a/src/github/code-scanning-alert.ts b/src/github/code-scanning-alert.ts
index 6f3f52605b..f0a3600881 100644
--- a/src/github/code-scanning-alert.ts
+++ b/src/github/code-scanning-alert.ts
@@ -5,18 +5,19 @@ import {
 import { emitWebhookProcessedMetrics } from "utils/webhook-utils";
 import { WebhookContext } from "../routes/github/webhook/webhook-context";
 import { booleanFlag, BooleanFlags } from "config/feature-flags";
+import { JiraClient } from "../jira/client/jira-client";
 
-export const codeScanningAlertWebhookHandler = async (context: WebhookContext, jiraClient, _util, gitHubInstallationId: number): Promise<void> => {
+export const codeScanningAlertWebhookHandler = async (context: WebhookContext, jiraClient: JiraClient, _util, gitHubInstallationId: number): Promise<void> => {
 	await Promise.all([handleRemoteLinks(context, jiraClient, gitHubInstallationId), handleSecurityVulnerability(context, jiraClient, gitHubInstallationId)]);
 };
 
-export const handleRemoteLinks = async (context: WebhookContext, jiraClient, gitHubInstallationId: number): Promise<void> => {
+export const handleRemoteLinks = async (context: WebhookContext, jiraClient: JiraClient, gitHubInstallationId: number): Promise<void> => {
 	context.log = context.log.child({
 		gitHubInstallationId,
 		jiraHost: jiraClient.baseURL
 	});
 
-	const jiraPayload = await transformCodeScanningAlert(context, gitHubInstallationId, jiraClient.baseUrl);
+	const jiraPayload = await transformCodeScanningAlert(context, gitHubInstallationId, jiraClient.baseURL);
 
 	if (!jiraPayload) {
 		context.log.info({ noop: "no_jira_payload_code_scanning_alert" }, "Halting further execution for code scanning alert since remote link payload is empty");
@@ -37,7 +38,7 @@ export const handleRemoteLinks = async (context: WebhookContext, jiraClient, git
 	);
 };
 
-export const handleSecurityVulnerability = async (context: WebhookContext, jiraClient, gitHubInstallationId: number): Promise<void> => {
+export const handleSecurityVulnerability = async (context: WebhookContext, jiraClient: JiraClient, gitHubInstallationId: number): Promise<void> => {
 	context.log = context.log.child({
 		gitHubInstallationId,
 		jiraHost: jiraClient.baseURL
diff --git a/src/github/installation.ts b/src/github/installation.ts
index 13ebed820e..17c3f7f039 100644
--- a/src/github/installation.ts
+++ b/src/github/installation.ts
@@ -64,7 +64,7 @@ export const installationWebhookHandler = async (
 		const webhookReceived = context.webhookReceived;
 		webhookReceived && emitWebhookProcessedMetrics(
 			new Date(webhookReceived).getTime(),
-			`installation-${action}`,
+			`installation-${action ?? "undefined"}`,
 			jiraClient.baseURL,
 			logger,
 			jiraResponse?.status,
diff --git a/src/github/issue-comment.ts b/src/github/issue-comment.ts
index bba0e2c5fb..8d90f10ea6 100644
--- a/src/github/issue-comment.ts
+++ b/src/github/issue-comment.ts
@@ -54,7 +54,7 @@ export const issueCommentWebhookHandler = async (
 		);
 	}
 
-	context.log.info(`Updating comment in GitHub with ID ${comment.id}`);
+	context.log.info(`Updating comment in GitHub with ID ${comment.id as number}`);
 	const updatedIssueComment: GitHubIssueCommentData = {
 		body: linkifiedBody,
 		owner,
@@ -83,7 +83,10 @@ export const issueCommentWebhookHandler = async (
 
 const syncIssueCommentsToJira = async (jiraHost: string, context: WebhookContext, gitHubInstallationClient: GitHubInstallationClient) => {
 	const { comment, repository, issue } = context.payload;
-	const { body: gitHubMessage, id: gitHubId, html_url: gitHubCommentUrl } = comment;
+	const { id: gitHubId } = comment;
+	const gitHubLogin: string = comment.user?.login ?? "undefined";
+	const gitHubMessage: string = comment.body ?? "undefined";
+	const gitHubCommentUrl: string = comment.html_url ?? "undefined";
 	const pullRequest = await gitHubInstallationClient.getPullRequest(repository.owner.login, repository.name, issue.number);
 	// Note: we are only considering the branch name here. Should we also check for pr titles?
 	const issueKey = jiraIssueKeyParser(pullRequest.data.head.ref)[0] || "";
@@ -106,7 +109,7 @@ const syncIssueCommentsToJira = async (jiraHost: string, context: WebhookContext
 				"content": [
 					{
 						"type": "text",
-						"text": `${comment.user.login}`,
+						"text": `${gitHubLogin}`,
 						"marks": [
 							{
 								"type": "strong"
diff --git a/src/github/repository.ts b/src/github/repository.ts
index 6b7c5295f3..47b3645bfd 100644
--- a/src/github/repository.ts
+++ b/src/github/repository.ts
@@ -55,7 +55,7 @@ export const deleteRepositoryWebhookHandler = async (context: WebhookContext, ji
 		return;
 	}
 
-	context.log.info(`Deleting dev info for repo ${context.payload.repository?.id}`);
+	context.log.info(`Deleting dev info for repo ${context.payload.repository?.id as number}`);
 
 	const { id: repositoryId } = context.payload.repository;
 
diff --git a/src/jira/client/jira-client.ts b/src/jira/client/jira-client.ts
index 5df1a41fda..d2babe9db1 100644
--- a/src/jira/client/jira-client.ts
+++ b/src/jira/client/jira-client.ts
@@ -82,7 +82,7 @@ export interface JiraClient {
 		) => Promise<DeploymentsResult>;
 	},
 	remoteLink: {
-		submit: (data: any, options?: JiraSubmitOptions) => Promise<void>;
+		submit: (data: any, options?: JiraSubmitOptions) => Promise<AxiosResponse>;
 	},
 	security: {
 		submitVulnerabilities: (data: JiraVulnerabilityBulkSubmitData, options?: JiraSubmitOptions) => Promise<AxiosResponse>;
@@ -461,7 +461,7 @@ export const getJiraClient = async (
 					operationType: options?.operationType || "NORMAL"
 				};
 				logger.info("Sending remoteLinks payload to jira.");
-				await instance.post("/rest/remotelinks/1.0/bulk", payload);
+				return await instance.post("/rest/remotelinks/1.0/bulk", payload);
 			}
 		},
 		security: {
@@ -498,7 +498,7 @@ export const getJiraClient = async (
 const handleSubmitVulnerabilitiesResponse = (response: AxiosResponse, logger: Logger) => {
 	const rejectedEntities = response.data?.rejectedEntities;
 	if (rejectedEntities?.length > 0) {
-		logger.warn({ rejectedEntities }, `Data depot rejected ${rejectedEntities.length} vulnerabilities`);
+		logger.warn({ rejectedEntities }, `Data depot rejected ${rejectedEntities.length as number} vulnerabilities`);
 	}
 };
 
diff --git a/src/jira/util/jira-client-util.ts b/src/jira/util/jira-client-util.ts
index f46f9e1f1f..4c33008fcc 100644
--- a/src/jira/util/jira-client-util.ts
+++ b/src/jira/util/jira-client-util.ts
@@ -2,10 +2,11 @@ import { envVars }  from "config/env";
 import { getLogger } from "config/logger";
 import { JiraIssue } from "interfaces/jira";
 import { jiraIssueInSquareBracketsRegex } from "utils/jira-utils";
+import { JiraClient } from "~/src/jira/client/jira-client";
 
 const logger = getLogger("jira.util");
 
-export const getJiraUtil = (jiraClient) => {
+export const getJiraUtil = (jiraClient: JiraClient) => {
 	const containsReferenceLink = (line: string) => {
 		// reference text links should have 2 parts only
 		if (line.split(" ").length === 2) {
diff --git a/src/jira/util/jwt.test.ts b/src/jira/util/jwt.test.ts
index 95a13dc202..713f1a705d 100644
--- a/src/jira/util/jwt.test.ts
+++ b/src/jira/util/jwt.test.ts
@@ -49,7 +49,7 @@ describe("jwt", () => {
 			query,
 			method: "GET",
 			pathname: "/jira/configuration",
-			url: `/jira/configuration?${new URLSearchParams(query)}`
+			url: `/jira/configuration?${new URLSearchParams(query).toString()}`
 		};
 	};
 
@@ -91,7 +91,7 @@ describe("jwt", () => {
 			session: {
 				jiraHost: "https://test.atlassian.net"
 			},
-			url: `/jira/configuration?${new URLSearchParams(testQueryParams)}`,
+			url: `/jira/configuration?${new URLSearchParams(testQueryParams).toString()}`,
 			log: getLogger("jwt.test")
 		} as any;
 
@@ -170,7 +170,7 @@ describe("jwt", () => {
 				return {
 					...baseRequest,
 					query,
-					url: `/jira/configuration?${new URLSearchParams(query)}`
+					url: `/jira/configuration?${new URLSearchParams(query).toString()}`
 				};
 			};
 
diff --git a/src/jira/util/jwt.ts b/src/jira/util/jwt.ts
index fbd0d18f40..02100be628 100644
--- a/src/jira/util/jwt.ts
+++ b/src/jira/util/jwt.ts
@@ -8,6 +8,7 @@ import { queryAtlassianConnectPublicKey } from "./query-atlassian-connect-public
 import { includes, isEmpty } from "lodash";
 import { createHash } from "crypto";
 import url, { UrlWithParsedQuery } from "url";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 const JWT_PARAM = "jwt";
 const AUTH_HEADER = "authorization"; // the header name appears as lower-case
@@ -115,22 +116,22 @@ export const validateQsh = (tokenType: TokenType, qsh: string, request: JWTReque
 
 export const validateJwtClaims = (verifiedClaims: { exp: number, qsh: string | undefined }, tokenType: TokenType, request: JWTRequest): void => {
 	if (!verifiedClaims.qsh) {
-		throw "JWT validation Failed, no qsh";
+		throw new Error("JWT validation Failed, no qsh");
 	}
 
 	// 3 second leeway in case of time drift
 	if (verifiedClaims.exp && (Date.now() / 1000 - 3) >= verifiedClaims.exp) {
-		throw "JWT validation failed, token is expired";
+		throw new Error("JWT validation failed, token is expired");
 	}
 
 	if (!validateQsh(tokenType, verifiedClaims.qsh, request)) {
-		throw "JWT Verification Failed, wrong qsh";
+		throw new Error("JWT Verification Failed, wrong qsh");
 	}
 };
 
 const validateSymmetricJwt = (secret: string, request: JWTRequest, tokenType: TokenType, token?: string): void => {
 	if (!token) {
-		throw "Could not find authentication data on request";
+		throw new Error("Could not find authentication data on request");
 	}
 
 	const algorithm = getAlgorithm(token);
@@ -139,20 +140,20 @@ const validateSymmetricJwt = (secret: string, request: JWTRequest, tokenType: To
 	let unverifiedClaims: any;
 	try {
 		unverifiedClaims = decodeSymmetric(token, "", algorithm, true); // decode without verification;
-	} catch (e) {
-		throw `Invalid JWT: ${e.message}`;
+	} catch (e: unknown) {
+		throw new Error(`Invalid JWT: ${errorStringFromUnknown(e)}`);
 	}
 
 	if (!unverifiedClaims.iss) {
-		throw "JWT claim did not contain the issuer (iss) claim";
+		throw new Error("JWT claim did not contain the issuer (iss) claim");
 	}
 
 	/* eslint-disable @typescript-eslint/no-explicit-any*/
 	let verifiedClaims: any; //due to decodeSymmetric return any
 	try {
 		verifiedClaims = decodeSymmetric(token, secret, algorithm, false);
-	} catch (error) {
-		throw `Unable to decode JWT token: ${error}`;
+	} catch (e: unknown) {
+		throw new Error(`Unable to decode JWT token: ${errorStringFromUnknown(e)}`);
 	}
 
 	validateJwtClaims(verifiedClaims, tokenType, request);
@@ -212,7 +213,7 @@ export const validateAsymmetricJwtTokenMiddleware = async (req: Request, res: Re
 export const validateAsymmetricJwtToken = async (request: JWTRequest, token?: string, isStaginTenant = false) => {
 
 	if (!token) {
-		throw "JWT Verification Failed, no token present";
+		throw new Error("JWT Verification Failed, no token present");
 	}
 
 	const publicKey = await queryAtlassianConnectPublicKey(getKeyId(token), isStaginTenant);
@@ -220,13 +221,13 @@ export const validateAsymmetricJwtToken = async (request: JWTRequest, token?: st
 
 	const issuer = unverifiedClaims.iss;
 	if (!issuer) {
-		throw "JWT claim did not contain the issuer (iss) claim";
+		throw new Error("JWT claim did not contain the issuer (iss) claim");
 	}
 
 	if (isEmpty(unverifiedClaims.aud) ||
 		!unverifiedClaims.aud[0] ||
 		!includes(ALLOWED_BASE_URLS, unverifiedClaims.aud[0].replace(/\/$/, ""))) {
-		throw "JWT claim did not contain the correct audience (aud) claim";
+		throw new Error("JWT claim did not contain the correct audience (aud) claim");
 	}
 
 	const verifiedClaims = decodeAsymmetricToken(token, publicKey, false);
@@ -269,7 +270,7 @@ export const createCanonicalRequest = (req: JWTRequest, checkBodyForParams?: boo
 	CANONICAL_QUERY_SEPARATOR +
 	canonicalizeQueryString(req, checkBodyForParams);
 
-const canonicalizeMethod = (req) => req.method.toUpperCase();
+const canonicalizeMethod = (req: JWTRequest) => req.method.toUpperCase();
 
 const canonicalizeUri = (req: JWTRequest) => {
 	let path = req.pathname;
diff --git a/src/middleware/github-webhook-middleware.ts b/src/middleware/github-webhook-middleware.ts
index 309d0c1874..bf51858516 100644
--- a/src/middleware/github-webhook-middleware.ts
+++ b/src/middleware/github-webhook-middleware.ts
@@ -60,7 +60,7 @@ const isStateChangeBranchCreateOrDeploymentAction = (action) =>
 const extractWebhookEventNameFromContext = (context: WebhookContext): string => {
 	let webhookEvent = context.name;
 	if (context.payload?.action) {
-		webhookEvent = `${webhookEvent}.${context.payload.action}`;
+		webhookEvent = `${webhookEvent}.${context.payload.action as string}`;
 	}
 	return webhookEvent;
 };
@@ -116,7 +116,7 @@ export const GithubWebhookMiddleware = (
 			fields: {
 				webhookId,
 				gitHubInstallationId,
-				gitHubServerAppIdPk: "" + gitHubAppId,
+				gitHubServerAppIdPk: gitHubAppId?.toString() ?? "undefined",
 				event: webhookEvent,
 				webhookReceived,
 				repoName,
@@ -181,7 +181,7 @@ export const GithubWebhookMiddleware = (
 
 		context.sentry?.setTag(
 			"transaction",
-			`webhook:${context.name}.${context.payload.action}`
+			`webhook:${context.name}.${context.payload.action as string}`
 		);
 
 		for (const subscription of subscriptions) {
diff --git a/src/middleware/jira-symmetric-jwt-middleware.ts b/src/middleware/jira-symmetric-jwt-middleware.ts
index c12c74d22c..dcdd04d431 100644
--- a/src/middleware/jira-symmetric-jwt-middleware.ts
+++ b/src/middleware/jira-symmetric-jwt-middleware.ts
@@ -12,6 +12,7 @@ import { matchRouteWithPattern } from "~/src/util/match-route-with-pattern";
 import { fetchAndSaveUserJiraAdminStatus } from "middleware/jira-admin-permission-middleware";
 import { envVars } from "~/src/config/env";
 import { booleanFlag, BooleanFlags } from "config/feature-flags";
+import { errorStringFromUnknown } from "../util/error-string-from-unknown";
 
 export const jiraSymmetricJwtMiddleware = async (req: Request, res: Response, next: NextFunction) => {
 	const authHeader = req.headers["authorization"] as string;
@@ -79,9 +80,9 @@ const getIssuer = (token: string, logger: Logger): string | undefined => {
 	let unverifiedClaims;
 	try {
 		unverifiedClaims = decodeSymmetric(token, "", getAlgorithm(token), true); // decode without verification;
-	} catch (err) {
+	} catch (err: unknown) {
 		logger.warn({ err }, "Invalid JWT");
-		throw new Error(`Invalid JWT: ${err.message}`);
+		throw new Error(`Invalid JWT: ${errorStringFromUnknown(err)}`);
 	}
 
 	if (!unverifiedClaims.iss) {
@@ -113,9 +114,9 @@ const verifySymmetricJwt = async (req: Request, token: string, installation: Ins
 
 		verifyJwtClaims(claims, tokenType, req);
 		return claims;
-	} catch (err) {
+	} catch (err: unknown) {
 		req.log.warn({ err }, "Invalid JWT");
-		throw new Error(`Unable to decode JWT token: ${err.message}`);
+		throw new Error(`Unable to decode JWT token: ${errorStringFromUnknown(err)}`);
 	}
 };
 
diff --git a/src/models/axios-error-event-decorator.ts b/src/models/axios-error-event-decorator.ts
index 1f1c6af09c..45822623e2 100644
--- a/src/models/axios-error-event-decorator.ts
+++ b/src/models/axios-error-event-decorator.ts
@@ -71,7 +71,7 @@ export class AxiosErrorEventDecorator {
 		return [
 			"{{ default }}",
 			this.response?.status,
-			`${this.request?.method} ${pathname}`
+			`${this.request?.method as string} ${pathname ?? "undefined"}`
 		];
 	}
 
diff --git a/src/models/encrypted-model.test.ts b/src/models/encrypted-model.test.ts
index d623d8c845..65aa8db265 100644
--- a/src/models/encrypted-model.test.ts
+++ b/src/models/encrypted-model.test.ts
@@ -66,7 +66,7 @@ const newId = () => {
 
 describe("Encrypted model", () => {
 	beforeEach(() => {
-		EncryptionClient.encrypt = jest.fn((_, p) => "encrypted:" + p) as any;
+		EncryptionClient.encrypt = jest.fn((_, p) => `encrypted:${p as string}`) as any;
 		EncryptionClient.decrypt = jest.fn((c) => c.substring("encrypted".length)) as any;
 	});
 
diff --git a/src/models/installation.test.ts b/src/models/installation.test.ts
index 91bce382a4..04d8edb462 100644
--- a/src/models/installation.test.ts
+++ b/src/models/installation.test.ts
@@ -89,7 +89,7 @@ describe("Installation", () => {
 					insert into "Installations"
 					("secrets", "encryptedSharedSecret", "clientKey", "createdAt", "updatedAt")
 					values
-					('xxxxx', 'encrypted:some-plain-text', '${clientKey}', now(), now())
+					('xxxxx', 'encrypted:some-plain-text', '${clientKey as string}', now(), now())
 				`, {
 			type: QueryTypes.INSERT
 		});
@@ -100,7 +100,7 @@ describe("Installation", () => {
 		const found = await Installation.sequelize?.query(`
 			select "encryptedSharedSecret" from "Installations" where "clientKey" = '${hashedClientKey}'
 		`, { plain: true });
-		if (!found) throw new Error("Cannot find installation by clientKey " + clientKey);
+		if (!found) throw new Error(`Cannot find installation by clientKey ${clientKey as string}`);
 		return found.encryptedSharedSecret;
 	};
 });
diff --git a/src/rest/middleware/jira-admin/jira-admin-check.test.ts b/src/rest/middleware/jira-admin/jira-admin-check.test.ts
index c7b5c401a7..ded8f85254 100644
--- a/src/rest/middleware/jira-admin/jira-admin-check.test.ts
+++ b/src/rest/middleware/jira-admin/jira-admin-check.test.ts
@@ -47,7 +47,7 @@ describe("Jira Admin Check", () => {
 						})
 					} as any;
 				} else {
-					throw new Error("Wrong installation " + reqInst);
+					throw new Error(`Wrong installation ${reqInst.toString()}`);
 				}
 			});
 
diff --git a/src/rest/routes/analytics-proxy/index.test.ts b/src/rest/routes/analytics-proxy/index.test.ts
index efde34e994..1fc17ee9ac 100644
--- a/src/rest/routes/analytics-proxy/index.test.ts
+++ b/src/rest/routes/analytics-proxy/index.test.ts
@@ -15,7 +15,7 @@ describe("AnalyticsProxyHandler", () => {
 		iss = "jira-client-key",
 		exp = Date.now() / 1000 + 10000,
 		qsh = "context-qsh",
-		sub = "myAccount" } = {}): any => {
+		sub = "myAccount" } = {}): string => {
 		return encodeSymmetric({
 			qsh,
 			iss,
diff --git a/src/rest/routes/github-apps/index.test.ts b/src/rest/routes/github-apps/index.test.ts
index 135c7c5410..29a96b156b 100644
--- a/src/rest/routes/github-apps/index.test.ts
+++ b/src/rest/routes/github-apps/index.test.ts
@@ -9,7 +9,7 @@ describe("rest oauth router", () => {
 		secret = testSharedSecret,
 		iss = "jira-client-key",
 		exp = Date.now() / 1000 + 10000,
-		qsh = "context-qsh" } = {}): any => {
+		qsh = "context-qsh" } = {}): string => {
 		return encodeSymmetric({
 			qsh,
 			iss,
diff --git a/src/rest/routes/github-orgs/index.test.ts b/src/rest/routes/github-orgs/index.test.ts
index ec59e4691b..96a4bed641 100644
--- a/src/rest/routes/github-orgs/index.test.ts
+++ b/src/rest/routes/github-orgs/index.test.ts
@@ -43,7 +43,7 @@ describe("Test cases for GitHub Org Route", () => {
 		secret = testSharedSecret,
 		iss = "jira-client-key",
 		exp = Date.now() / 1000 + 10000,
-		qsh = "context-qsh" } = {}): any => {
+		qsh = "context-qsh" } = {}): string => {
 		return encodeSymmetric({
 			qsh,
 			iss,
diff --git a/src/rest/routes/jira/index.test.ts b/src/rest/routes/jira/index.test.ts
index aaef3bf3f8..33eb876c82 100644
--- a/src/rest/routes/jira/index.test.ts
+++ b/src/rest/routes/jira/index.test.ts
@@ -10,7 +10,7 @@ describe("Testing the route for fetching the Cloud Id", () => {
 		secret = testSharedSecret,
 		iss = "jira-client-key",
 		exp = Date.now() / 1000 + 10000,
-		qsh = "context-qsh" } = {}): any => {
+		qsh = "context-qsh" } = {}): string => {
 		return encodeSymmetric({
 			qsh,
 			iss,
diff --git a/src/rest/routes/oauth/index.test.ts b/src/rest/routes/oauth/index.test.ts
index a8b50e85b9..5357f0da5f 100644
--- a/src/rest/routes/oauth/index.test.ts
+++ b/src/rest/routes/oauth/index.test.ts
@@ -11,7 +11,7 @@ describe("rest oauth router", () => {
 		secret = testSharedSecret,
 		iss = "jira-client-key",
 		exp = Date.now() / 1000 + 10000,
-		qsh = "context-qsh" } = {}): any => {
+		qsh = "context-qsh" } = {}): string => {
 		return encodeSymmetric({
 			qsh,
 			iss,
diff --git a/src/routes/api/api-router.ts b/src/routes/api/api-router.ts
index a129ae57e1..3bc573b32a 100644
--- a/src/routes/api/api-router.ts
+++ b/src/routes/api/api-router.ts
@@ -130,7 +130,7 @@ const cryptorDebugEndpoint = async (_req: Request, resp: Response) => {
 	try {
 		let data = "";
 		for (let i = 0; i < 10; i++) {
-			data = data + "-" + Math.floor((Math.random() * 10));
+			data = `${data}-${Math.floor((Math.random() * 10))}`;
 		}
 
 		const encrypted = await EncryptionClient.encrypt(EncryptionSecretKeyEnum.GITHUB_SERVER_APP, data);
diff --git a/src/routes/api/client-key/recover-client-key.ts b/src/routes/api/client-key/recover-client-key.ts
index a5503e7e93..097bf3a64a 100644
--- a/src/routes/api/client-key/recover-client-key.ts
+++ b/src/routes/api/client-key/recover-client-key.ts
@@ -94,7 +94,7 @@ const getAndVerifyplainClientKey = async ({ id, jiraHost, clientKey: hashedClien
 		//https://hello.atlassian.net/wiki/spaces/EDGE/pages/315794033/Whitelist+Proxy+-+Usage
 		//use whitelist proxy so that we can hit xxx.jira-dev.com
 		//Unless we don't care about those records in db?
-		const proxy = `http://${process.env.WHITELIST_PROXY_HOST}:${process.env.WHITELIST_PROXY_PORT}`;
+		const proxy = `http://${process.env.WHITELIST_PROXY_HOST ?? "undefined"}:${process.env.WHITELIST_PROXY_PORT ?? "undefined"}`;
 		const result = await axios.create({
 			baseURL: jiraHost,
 			httpAgent: new HttpProxyAgent(proxy),
diff --git a/src/routes/api/commits-from-date/reset-failed-and-pending-deployment-cursors.ts b/src/routes/api/commits-from-date/reset-failed-and-pending-deployment-cursors.ts
index 7f0b9a659e..fa8b63928a 100644
--- a/src/routes/api/commits-from-date/reset-failed-and-pending-deployment-cursors.ts
+++ b/src/routes/api/commits-from-date/reset-failed-and-pending-deployment-cursors.ts
@@ -55,7 +55,7 @@ export const ResetFailedAndPendingDeploymentCursorPost = async (req: Request, re
 			count++;
 			lastId = repo.id;
 		}
-		info(`${count} repo sync states updated, last RepoSyncState id is ${lastId})`);
+		info(`${count} repo sync states updated, last RepoSyncState id is ${lastId ? lastId.toString() : "undefined"})`);
 
 		res.end();
 
diff --git a/src/routes/api/data-cleanup/cleanup-reposyncstates.ts b/src/routes/api/data-cleanup/cleanup-reposyncstates.ts
index ea1f6b6f95..2b311d3aa5 100644
--- a/src/routes/api/data-cleanup/cleanup-reposyncstates.ts
+++ b/src/routes/api/data-cleanup/cleanup-reposyncstates.ts
@@ -61,7 +61,7 @@ const safeParseResult = (result: object, commitToDB: boolean) => {
 						}
 					]
 				*/
-			return `${result[1].rowCount} rows deleted`;
+			return `${(result[1].rowCount as number)} rows deleted`;
 		} else {
 			/*
 			 * something like   result: [
@@ -102,7 +102,7 @@ const safeParseResult = (result: object, commitToDB: boolean) => {
 					}
 				]
 			 */
-			return result[0].map((r: object) => safeJsonStringify(r)).join("\n");
+			return result[0].map((r: object) => safeJsonStringify(r)).join("\n") as string;
 		}
 	} catch (_) {
 		return result;
diff --git a/src/routes/api/db-migrations/db-migration-down.ts b/src/routes/api/db-migrations/db-migration-down.ts
index 8312fb9f1c..10a4710f98 100644
--- a/src/routes/api/db-migrations/db-migration-down.ts
+++ b/src/routes/api/db-migrations/db-migration-down.ts
@@ -53,7 +53,7 @@ const validateScriptAgainstDB = async (targetScript: string) => {
 	if (lastScript.length < 1) {
 		throw {
 			statusCode: 500,
-			message: `There're no scripts in db to migration down, stop proceeding. \n ${lastScript}`
+			message: `There're no scripts in db to migration down, stop proceeding. \n}`
 		};
 	}
 
diff --git a/src/routes/api/db-migrations/db-migration-utils.ts b/src/routes/api/db-migrations/db-migration-utils.ts
index 06238e7b50..513a92d0f4 100644
--- a/src/routes/api/db-migrations/db-migration-utils.ts
+++ b/src/routes/api/db-migrations/db-migration-utils.ts
@@ -17,8 +17,8 @@ const logger = getLogger("DBMigration");
  *
  * @returns The common param in req.body `targetScript` to migrate up or down
  */
-export const getTargetScript = (req: Request) => {
-	const targetScript = (req.body || {}).targetScript;
+export const getTargetScript = (req: Request) : string => {
+	const targetScript: string | null = (req.body || {}).targetScript;
 	if (!targetScript) {
 		throw {
 			statusCode: 400,
@@ -71,7 +71,7 @@ export const runDbMigration = async (targetScript: string, ops: DBMigrationType)
 		default:
 			throw {
 				statusCode: 500,
-				message: `Fail to execute db migration type ${ops}`
+				message: `Fail to execute db migration type`
 			};
 	}
 	const { stdout, stderr } = await exec(cmd, {
diff --git a/src/routes/api/installation/api-installation-get.ts b/src/routes/api/installation/api-installation-get.ts
index 17ef43d76e..83cf48015e 100644
--- a/src/routes/api/installation/api-installation-get.ts
+++ b/src/routes/api/installation/api-installation-get.ts
@@ -3,6 +3,7 @@ import { Subscription } from "models/subscription";
 import { createAppClient } from "~/src/util/get-github-client-config";
 import { AxiosResponse } from "axios";
 import { Octokit } from "@octokit/rest";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const ApiInstallationGet = async (req: Request, res: Response): Promise<void> => {
 	const { installationId, gitHubAppId: gitHubAppIdStr } = req.params;
@@ -46,7 +47,7 @@ export const ApiInstallationGet = async (req: Request, res: Response): Promise<v
 				req.log.error({ ...response }, "Failed installation");
 				return {
 					id: response.id,
-					error: response.err.message + ". More details in logs",
+					error: `${errorStringFromUnknown(response.err)}. More details in logs`,
 					deleted: response.deleted
 				};
 			});
@@ -56,7 +57,7 @@ export const ApiInstallationGet = async (req: Request, res: Response): Promise<v
 			connections,
 			failedConnections,
 			hasConnections: connections.length > 0 || failedConnections.length > 0,
-			syncStateUrl: `${req.protocol}://${req.get("host")}/api/${installationId}/${encodeURIComponent(jiraHost)}/syncstate`
+			syncStateUrl: `${req.protocol}://${req.get("host") ?? ""}/api/${installationId}/${encodeURIComponent(jiraHost)}/syncstate`
 		});
 	} catch (err) {
 		req.log.error({ installationId, err }, "Error getting installation");
diff --git a/src/routes/api/jira/api-jira-uninstall-post.ts b/src/routes/api/jira/api-jira-uninstall-post.ts
index b55a976a1a..edaa09d710 100644
--- a/src/routes/api/jira/api-jira-uninstall-post.ts
+++ b/src/routes/api/jira/api-jira-uninstall-post.ts
@@ -27,7 +27,7 @@ export const ApiJiraUninstallPost = async (request: Request, response: Response)
 		return;
 	}
 	request.log.info(
-		`Forcing uninstall for ${response.locals.installation.clientKey}`
+		`Forcing uninstall for ${response.locals.installation.clientKey as string}`
 	);
 	await JiraEventsUninstallPost(request, response);
 };
diff --git a/src/routes/github/configuration/github-configuration-app-installs-get.ts b/src/routes/github/configuration/github-configuration-app-installs-get.ts
index d56a85551a..4e5d338ac5 100644
--- a/src/routes/github/configuration/github-configuration-app-installs-get.ts
+++ b/src/routes/github/configuration/github-configuration-app-installs-get.ts
@@ -27,7 +27,7 @@ export const GithubConfigurationAppInstallsGet = async (req: Request, res: Respo
 	// We need to re-generate the URL for server because API gateway might override the hostname
 	if (data.html_url.indexOf("/github-apps/") > 0) {
 		// https://docs.github.com/en/enterprise-server@3.8/apps/maintaining-github-apps/installing-github-apps
-		newInstallationUrl = gitHubAppConfig.hostname + "/github-apps/" + data.html_url.split("/github-apps/")[1] + "/installations/new";
+		newInstallationUrl = `${gitHubAppConfig.hostname as string}/github-apps/${data.html_url.split("/github-apps/")[1]}/installations/new`;
 	} else {
 		newInstallationUrl = `${data.html_url}/installations/new`;
 	}
diff --git a/src/routes/github/configuration/github-configuration-get.ts b/src/routes/github/configuration/github-configuration-get.ts
index 2b2a05e309..a32af578a1 100644
--- a/src/routes/github/configuration/github-configuration-get.ts
+++ b/src/routes/github/configuration/github-configuration-get.ts
@@ -17,6 +17,7 @@ import {
 	registerSubscriptionDeferredInstallPayloadRequest,
 	SubscriptionDeferredInstallPayload
 } from "services/subscription-deferred-install-service";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 interface ConnectedStatus {
 	// TODO: really need to type this sync status
@@ -99,7 +100,7 @@ export const getInstallationsWithAdmin = async (
 			return false;
 		});
 		const [isAdmin, numberOfRepos] = await Promise.all([checkAdmin, numberOfReposPromise]);
-		log.info("Number of repos in the org received via GraphQL: " + numberOfRepos);
+		log.info(`Number of repos in the org received via GraphQL: ${numberOfRepos}`);
 
 		let deferredInstallUrl: string | undefined;
 
@@ -138,9 +139,9 @@ const removeFailedConnectionsFromDb = async (logger: Logger, installations: Inst
 					host: jiraHost,
 					gitHubAppId
 				});
-			} catch (err) {
-				const deleteSubscriptionError = `Failed to delete subscription: ${err}`;
-				logger.error(deleteSubscriptionError);
+			} catch (err: unknown) {
+				const deleteSubscriptionError = `Failed to delete subscription: ${errorStringFromUnknown(err)}`;
+				logger.error({ err }, deleteSubscriptionError);
 			}
 		}));
 };
@@ -157,7 +158,8 @@ export const GithubConfigurationGet = async (req: Request, res: Response, next:
 
 	const log = req.log.child({ jiraHost });
 
-	const { gitHubAppId, uuid: gitHubAppUuid } = gitHubAppConfig;
+	const { uuid: gitHubAppUuid } = gitHubAppConfig;
+	const gitHubAppId: number = gitHubAppConfig.gitHubAppId;
 
 	gitHubAppId ? req.log.debug(`Displaying orgs that have GitHub Enterprise app ${gitHubAppId} installed.`)
 		: req.log.debug("Displaying orgs that have GitHub Cloud app installed.");
diff --git a/src/routes/github/create-branch/github-branches-get.test.ts b/src/routes/github/create-branch/github-branches-get.test.ts
index 6fc130dd96..d9871ec835 100644
--- a/src/routes/github/create-branch/github-branches-get.test.ts
+++ b/src/routes/github/create-branch/github-branches-get.test.ts
@@ -144,7 +144,7 @@ describe("Getting GitHub Branches securely avoiding XSS attacks", () => {
 });
 
 const defaultBranchForXSS = "DEFAULTTESTXSS\"><script>alert('🔫🔫🔫🔫🔫🔫')</script>";
-const setupNockForXSSBranches = (gitHubInstallationId) => {
+const setupNockForXSSBranches = (gitHubInstallationId: number) => {
 
 	githubNock
 		.post(`/app/installations/${gitHubInstallationId}/access_tokens`)
diff --git a/src/routes/github/create-branch/github-create-branch-get.test.ts b/src/routes/github/create-branch/github-create-branch-get.test.ts
index 55ab1ad1e4..cdb46f0471 100644
--- a/src/routes/github/create-branch/github-create-branch-get.test.ts
+++ b/src/routes/github/create-branch/github-create-branch-get.test.ts
@@ -19,12 +19,12 @@ for (let i = 0; i < 100; i++) {
 	REPOS_FIXTURE_EXPANDED.data.viewer.repositories.edges.push({
 		node: {
 			id: 1000 + i,
-			name: "SampleRepo" + i,
-			full_name: "user1/SampleRepo" + i,
+			name: `SampleRepo${i}`,
+			full_name: `user1/SampleRepo${i}`,
 			owner: {
 				login: "user1"
 			},
-			html_url: "https://github.com/user1/SampleRepo" + i,
+			html_url: `https://github.com/user1/SampleRepo${i}`,
 			updated_at: new Date(i * 1000).toISOString()
 		}
 	});
diff --git a/src/routes/github/create-branch/github-create-branch-get.ts b/src/routes/github/create-branch/github-create-branch-get.ts
index 072a72f85f..397382c341 100644
--- a/src/routes/github/create-branch/github-create-branch-get.ts
+++ b/src/routes/github/create-branch/github-create-branch-get.ts
@@ -11,10 +11,8 @@ import { RepoSyncState } from "models/reposyncstate";
 const MAX_REPOS_RETURNED = 20;
 
 export const GithubCreateBranchGet = async (req: Request, res: Response, next: NextFunction): Promise<void> => {
-	const {
-		gitHubAppConfig,
-		jiraHost
-	} = res.locals;
+	const gitHubAppConfig = res.locals.gitHubAppConfig;
+	const jiraHost: string = res.locals.jiraHost;
 	const logger = getLogger("github-create-branch-get", {
 		fields: {
 			...req.log?.fields,
diff --git a/src/routes/github/create-branch/github-create-branch-options-get.ts b/src/routes/github/create-branch/github-create-branch-options-get.ts
index 6f5623d54b..5100e9c634 100644
--- a/src/routes/github/create-branch/github-create-branch-options-get.ts
+++ b/src/routes/github/create-branch/github-create-branch-options-get.ts
@@ -16,7 +16,7 @@ export const GithubCreateBranchOptionsGet = async (req: Request, res: Response,
 		return next(new Error(Errors.MISSING_ISSUE_KEY));
 	}
 
-	const jiraHost = res.locals.jiraHost;
+	const jiraHost: string = res.locals.jiraHost;
 
 	const logger = getLogger("github-create-branch-get-options", {
 		fields: {
@@ -43,7 +43,7 @@ export const GithubCreateBranchOptionsGet = async (req: Request, res: Response,
 		return;
 	}
 
-	const url = new URL(`${req.protocol}://${req.get("host")}${req.originalUrl}`);
+	const url = new URL(`${req.protocol}://${req.get("host") ?? ""}${req.originalUrl}`);
 	// Only has cloud instance
 	if (servers.hasCloudServer && servers.gheServerInfos.length == 0) {
 		logger.info("redirecting to cloud.");
diff --git a/src/routes/github/create-branch/github-create-branch-post.frontend.test.ts b/src/routes/github/create-branch/github-create-branch-post.frontend.test.ts
index 323c96634b..cb82f57559 100644
--- a/src/routes/github/create-branch/github-create-branch-post.frontend.test.ts
+++ b/src/routes/github/create-branch/github-create-branch-post.frontend.test.ts
@@ -79,7 +79,7 @@ describe("github-create-branch-post.frontend", () => {
 			]);
 		});
 
-		const expandSelector = async (text) => {
+		const expandSelector = async (text: string) => {
 			const elementWithTextLocator = await page.locator(`span.select2-chosen:has-text("${text}")`);
 			const element = await elementWithTextLocator.elementHandle();
 
@@ -162,6 +162,8 @@ describe("github-create-branch-post.frontend", () => {
 
 				await page.click("#createBranchBtn");
 				await page.waitForSelector("text=Github branch created");
+
+				expect(gheApiNock).toBeDone();
 			});
 		});
 	});
diff --git a/src/routes/github/create-branch/github-create-branch-post.ts b/src/routes/github/create-branch/github-create-branch-post.ts
index 0fb57864ef..dd8c2d016f 100644
--- a/src/routes/github/create-branch/github-create-branch-post.ts
+++ b/src/routes/github/create-branch/github-create-branch-post.ts
@@ -35,7 +35,8 @@ const getErrorMessages = (statusCode: number): string => {
 
 export const GithubCreateBranchPost = async (req: Request, res: Response): Promise<void> => {
 	const { gitHubAppConfig, jiraHost } = res.locals;
-	const { owner, repo, sourceBranchName, newBranchName } = req.body;
+	const { owner, repo, sourceBranchName } = req.body;
+	const newBranchName: string = req.body.newBranchName;
 	const logger = getLogger("github-create-branch-options-get", {
 		fields: req.log?.fields
 	});
diff --git a/src/routes/github/github-5ku-router.ts b/src/routes/github/github-5ku-router.ts
index ae6af9d90c..7aa8de6269 100644
--- a/src/routes/github/github-5ku-router.ts
+++ b/src/routes/github/github-5ku-router.ts
@@ -3,8 +3,8 @@ import sanitize from "sanitize-html";
 
 export const GitHub5KURedirectHandler = (req: Request, res: Response, next: NextFunction) => {
 	if (req.query["state"] === "spa") {
-		const sanitizedGitHubInstallationId = sanitize(String(req.query.installation_id || ""));
-		const sanitizedSetupAction = sanitize(String(req.query.setup_action || ""));
+		const sanitizedGitHubInstallationId: string = sanitize(String(req.query.installation_id || ""));
+		const sanitizedSetupAction: string = sanitize(String(req.query.setup_action || ""));
 		if (sanitizedGitHubInstallationId) {
 			res.redirect(`/rest/app/cloud/github-installed?installation_id=${sanitizedGitHubInstallationId}`);
 		} else if (sanitizedSetupAction) {
diff --git a/src/routes/github/github-oauth.ts b/src/routes/github/github-oauth.ts
index 88b98b1e3c..1290c4c92c 100644
--- a/src/routes/github/github-oauth.ts
+++ b/src/routes/github/github-oauth.ts
@@ -33,7 +33,8 @@ const getRedirectUrl = async (res: Response, state: string) => {
 	}
 	const scopes = ["user", "repo"];
 
-	const { hostname, clientId } = res.locals.gitHubAppConfig;
+	const hostname: string = res.locals.gitHubAppConfig.hostname;
+	const clientId: string = res.locals.gitHubAppConfig.clientId;
 	const callbackURI = `${appUrl}${callbackPath}`;
 	return `${hostname}/login/oauth/authorize?client_id=${clientId}&scope=${encodeURIComponent(scopes.join(" "))}&redirect_uri=${encodeURIComponent(callbackURI)}&state=${state}`;
 };
diff --git a/src/routes/github/github-router.test.ts b/src/routes/github/github-router.test.ts
index 0974094b6c..584783c61d 100644
--- a/src/routes/github/github-router.test.ts
+++ b/src/routes/github/github-router.test.ts
@@ -181,7 +181,7 @@ describe("GitHub router", () => {
 					.get("/github/configuration")
 					.set(
 						"Cookie",
-						`session=${cookies.session}; session.sig=${cookies["session.sig"]}`
+						`session=${cookies.session as string}; session.sig=${cookies["session.sig"] as string}`
 					)
 					.expect(302);
 
diff --git a/src/routes/github/manifest/github-manifest-complete-get.ts b/src/routes/github/manifest/github-manifest-complete-get.ts
index 5cf67667c0..18d7f689d1 100644
--- a/src/routes/github/manifest/github-manifest-complete-get.ts
+++ b/src/routes/github/manifest/github-manifest-complete-get.ts
@@ -43,7 +43,7 @@ export const GithubManifestCompleteGet = async (req: Request, res: Response) =>
 				}
 				: undefined
 		);
-		const gitHubAppConfig = await gitHubClient.createGitHubApp("" + req.query.code);
+		const gitHubAppConfig = await gitHubClient.createGitHubApp(req.query.code.toString());
 		await GitHubServerApp.install({
 			uuid,
 			appId: gitHubAppConfig.id,
diff --git a/src/routes/github/setup/github-setup-post.ts b/src/routes/github/setup/github-setup-post.ts
index 5c6e1828b6..6f923eafbf 100644
--- a/src/routes/github/setup/github-setup-post.ts
+++ b/src/routes/github/setup/github-setup-post.ts
@@ -25,7 +25,7 @@ const validateJiraSite = async (
 
 export const GithubSetupPost = async (req: Request, res: Response): Promise<void> => {
 	const { jiraHost, jiraDomain, jiraDomainMain, jiraDomainModal } = req.body;
-	const domain = jiraDomain || jiraDomainMain || jiraDomainModal || "";
+	const domain: string = jiraDomain || jiraDomainMain || jiraDomainModal || "";
 	const url = jiraHost || `https://${domain}.atlassian.net`;
 
 	req.log.debug({ jiraHost: url }, `Received github setup page request for jira`);
diff --git a/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-get.ts b/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-get.ts
index 85c6d32660..af1562ed34 100644
--- a/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-get.ts
+++ b/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-get.ts
@@ -18,7 +18,7 @@ export const GitHubSubscriptionDeferredInstallGet = async (req: Request, res: Re
 	res.render("subscription-deferred-install-approval-form.hbs", {
 		csrfToken: req.csrfToken(),
 		orgName: payload.orgName,
-		orgUrl: `${res.locals.gitHubAppConfig.hostname}/${payload.orgName}`,
+		orgUrl: `${res.locals.gitHubAppConfig.hostname as string}/${payload.orgName}`,
 		jiraHost: res.locals.jiraHost
 	});
 
diff --git a/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-post.ts b/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-post.ts
index 4462a470c3..73b2dd7ed5 100644
--- a/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-post.ts
+++ b/src/routes/github/subscription-deferred-install/github-subscription-deferred-install-post.ts
@@ -22,7 +22,7 @@ export const GithubSubscriptionDeferredInstallPost = async (req: Request, res: R
 	res.render("subscription-deferred-install-approval-form.hbs", {
 		success: true,
 		orgName: payload.orgName,
-		orgUrl: `${res.locals.gitHubAppConfig.hostname}/${payload.orgName}`,
+		orgUrl: `${res.locals.gitHubAppConfig.hostname as string}/${payload.orgName}`,
 		jiraHost: res.locals.jiraHost
 	});
 };
diff --git a/src/routes/github/webhook/webhook-receiver-post.ts b/src/routes/github/webhook/webhook-receiver-post.ts
index 4851bd65af..02f3e0c318 100644
--- a/src/routes/github/webhook/webhook-receiver-post.ts
+++ b/src/routes/github/webhook/webhook-receiver-post.ts
@@ -23,6 +23,7 @@ import { dependabotAlertWebhookHandler } from "~/src/github/dependabot-alert";
 import { extraLoggerInfo } from "./webhook-logging-extra";
 import { secretScanningAlertWebhookHandler } from "~/src/github/secret-scanning-alert";
 import { installationWebhookHandler } from "~/src/github/installation";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const WebhookReceiverPost = async (request: Request, response: Response): Promise<void> => {
 	const eventName = request.headers["x-github-event"] as string;
@@ -87,8 +88,8 @@ export const WebhookReceiverPost = async (request: Request, response: Response):
 		webhookContext.log.info("Webhook was successfully processed");
 		response.sendStatus(204);
 
-	} catch (err) {
-		(webhookContext?.log || logger).error({ err }, "Something went wrong, returning 400: " + err.message);
+	} catch (err: unknown) {
+		(webhookContext?.log || logger).error({ err }, `Something went wrong, returning 400: ${errorStringFromUnknown(err)}`);
 		response.sendStatus(400);
 	}
 };
diff --git a/src/routes/jira/atlassian-connect/jira-atlassian-connect-get.ts b/src/routes/jira/atlassian-connect/jira-atlassian-connect-get.ts
index 94ebcac14c..c88730fa7a 100644
--- a/src/routes/jira/atlassian-connect/jira-atlassian-connect-get.ts
+++ b/src/routes/jira/atlassian-connect/jira-atlassian-connect-get.ts
@@ -8,7 +8,7 @@ const isProd = instance === "production";
 
 // TODO: implement named routes (https://www.npmjs.com/package/named-routes) to facilitate rerouting between files
 export const postInstallUrl = "/jira";
-export const APP_NAME = `GitHub for Jira${isProd ? "" : ` (${instance})`}`;
+export const APP_NAME = `GitHub for Jira${isProd ? "" : ` (${instance ?? ""})`}`;
 export const LOGO_URL = "https://github.githubassets.com/images/modules/logos_page/GitHub-Mark.png";
 
 const adminCondition = [
diff --git a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-create-or-edit-get.ts b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-create-or-edit-get.ts
index 4668f221b1..40fce0971a 100644
--- a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-create-or-edit-get.ts
+++ b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-create-or-edit-get.ts
@@ -6,6 +6,7 @@ import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsScreenEventsEnum } from "interfaces/common";
 import { resolveIntoConnectConfig } from "utils/ghe-connect-config-temp-storage";
 import { getAllKnownHeaders } from "utils/http-headers";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectEnterpriseAppCreateOrEditGet = async (
 	req: Request,
@@ -79,7 +80,7 @@ export const JiraConnectEnterpriseAppCreateOrEditGet = async (
 			knownHttpHeadersLowerCase: getAllKnownHeaders()
 		});
 		req.log.debug("Jira create or edit app page rendered successfully.");
-	} catch (error) {
-		return next(new Error(`Failed to render Jira create or edit app page: ${error}`));
+	} catch (error: unknown) {
+		return next(new Error(`Failed to render Jira create or edit app page: ${errorStringFromUnknown(error)}`));
 	}
 };
diff --git a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-post.test.ts b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-post.test.ts
index ab1b5b4e3c..54f7f7132d 100644
--- a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-post.test.ts
+++ b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-post.test.ts
@@ -51,7 +51,7 @@ describe("jira-connect-enterprise-app-post", () => {
 			TEST_GHE_APP_PARTIAL = {
 				appId: 12321,
 				gitHubBaseUrl: gheUrl,
-				gitHubClientId: "client-id" + Math.random(),
+				gitHubClientId: "client-id" + Math.random().toString(),
 				gitHubClientSecret: "client-secret",
 				webhookSecret: "webhook-secret",
 				privateKey: fs.readFileSync(path.resolve(__dirname, "../../../../../../test/setup/test-key.pem"), { encoding: "utf8" }),
@@ -122,9 +122,9 @@ describe("jira-connect-enterprise-app-post", () => {
 				gitHubClientId: expect.stringMatching(/client-id.*/i),
 
 				secrets: null,
-				privateKey: "encrypted:" + TEST_GHE_APP_PARTIAL.privateKey,
-				gitHubClientSecret: "encrypted:" + TEST_GHE_APP_PARTIAL.gitHubClientSecret,
-				webhookSecret: "encrypted:" + TEST_GHE_APP_PARTIAL.webhookSecret,
+				privateKey: "encrypted:" + (TEST_GHE_APP_PARTIAL.privateKey as string),
+				gitHubClientSecret: "encrypted:" + (TEST_GHE_APP_PARTIAL.gitHubClientSecret as string),
+				webhookSecret: "encrypted:" + (TEST_GHE_APP_PARTIAL.webhookSecret as string),
 
 				apiKeyHeaderName: null,
 				encryptedApiKeyValue: null,
diff --git a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-put.ts b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-put.ts
index 62b92e8b07..e06c4ab6ee 100644
--- a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-put.ts
+++ b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-app-put.ts
@@ -3,6 +3,7 @@ import { GitHubServerApp } from "~/src/models/github-server-app";
 import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsTrackEventsEnum, AnalyticsTrackSource } from "interfaces/common";
 import { validateApiKeyInputsAndReturnErrorIfAny } from "utils/api-key-validator";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectEnterpriseAppPut = async (
 	req: Request,
@@ -47,7 +48,7 @@ export const JiraConnectEnterpriseAppPut = async (
 
 		res.status(202).send();
 		req.log.debug("Jira Connect Enterprise App updated successfully.");
-	} catch (error) {
+	} catch (error: unknown) {
 
 		await sendAnalytics(res.locals.jiraHost, AnalyticsEventTypes.TrackEvent, {
 			action: AnalyticsTrackEventsEnum.UpdateGitHubServerAppTrackEventName,
@@ -58,6 +59,6 @@ export const JiraConnectEnterpriseAppPut = async (
 		});
 
 		res.status(404).send({ message: "Failed to update GitHub App." });
-		return next(new Error(`Failed to update GitHub app: ${error}`));
+		return next(new Error(`Failed to update GitHub app: ${errorStringFromUnknown(error)}`));
 	}
 };
diff --git a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-apps-get.ts b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-apps-get.ts
index db9335c310..f2d84a0328 100644
--- a/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-apps-get.ts
+++ b/src/routes/jira/connect/enterprise/app/jira-connect-enterprise-apps-get.ts
@@ -3,6 +3,7 @@ import { GitHubServerApp } from "models/github-server-app";
 import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsScreenEventsEnum } from "interfaces/common";
 import { resolveIntoConnectConfig } from "utils/ghe-connect-config-temp-storage";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectEnterpriseAppsGet = async (
 	req: Request,
@@ -51,8 +52,8 @@ export const JiraConnectEnterpriseAppsGet = async (
 		}
 
 		req.log.debug("Jira Connect Enterprise App page rendered successfully.");
-	} catch (error) {
-		return next(new Error(`Failed to render Jira Connect Enterprise App page: ${error}`));
+	} catch (error: unknown) {
+		return next(new Error(`Failed to render Jira Connect Enterprise App page: ${errorStringFromUnknown(error)}`));
 	}
 };
 
diff --git a/src/routes/jira/connect/enterprise/jira-connect-enterprise-delete.ts b/src/routes/jira/connect/enterprise/jira-connect-enterprise-delete.ts
index fda5fd42fa..807ba0464d 100644
--- a/src/routes/jira/connect/enterprise/jira-connect-enterprise-delete.ts
+++ b/src/routes/jira/connect/enterprise/jira-connect-enterprise-delete.ts
@@ -4,6 +4,7 @@ import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsTrackEventsEnum, AnalyticsTrackSource } from "interfaces/common";
 import { isConnected } from "utils/is-connected";
 import { saveConfiguredAppProperties } from "utils/app-properties-utils";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectEnterpriseDelete = async (
 	req: Request,
@@ -32,7 +33,7 @@ export const JiraConnectEnterpriseDelete = async (
 
 		res.status(200).send({ success: true });
 		req.log.debug("Jira Connect Enterprise Server successfully deleted.");
-	} catch (error) {
+	} catch (error: unknown) {
 
 		await sendAnalytics(res.locals.jiraHost, AnalyticsEventTypes.TrackEvent, {
 			action: AnalyticsTrackEventsEnum.RemoveGitHubServerTrackEventName,
@@ -43,6 +44,6 @@ export const JiraConnectEnterpriseDelete = async (
 		});
 
 		res.status(200).send({ success: false, message: "Failed to delete GitHub Enterprise Server." });
-		return next(new Error(`Failed to DELETE GitHub Enterprise Server: ${error}`));
+		return next(new Error(`Failed to DELETE GitHub Enterprise Server: ${errorStringFromUnknown(error)}`));
 	}
 };
diff --git a/src/routes/jira/connect/enterprise/jira-connect-enterprise-get.ts b/src/routes/jira/connect/enterprise/jira-connect-enterprise-get.ts
index e266dde895..99c3894dba 100644
--- a/src/routes/jira/connect/enterprise/jira-connect-enterprise-get.ts
+++ b/src/routes/jira/connect/enterprise/jira-connect-enterprise-get.ts
@@ -4,6 +4,7 @@ import { chain, groupBy } from "lodash";
 import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsScreenEventsEnum } from "interfaces/common";
 import { getAllKnownHeaders } from "utils/http-headers";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectEnterpriseGet = async (
 	req: Request,
@@ -40,8 +41,8 @@ export const JiraConnectEnterpriseGet = async (
 		}
 
 		req.log.debug("Jira Connect Enterprise GET page rendered successfully.");
-	} catch (error) {
-		return next(new Error(`Failed to render Jira Connect Enterprise GET page: ${error}`));
+	} catch (error: unknown) {
+		return next(new Error(`Failed to render Jira Connect Enterprise GET page: ${errorStringFromUnknown(error)}`));
 	}
 };
 
diff --git a/src/routes/jira/connect/enterprise/jira-connect-enterprise-post.ts b/src/routes/jira/connect/enterprise/jira-connect-enterprise-post.ts
index 5a0f325375..058b42e585 100644
--- a/src/routes/jira/connect/enterprise/jira-connect-enterprise-post.ts
+++ b/src/routes/jira/connect/enterprise/jira-connect-enterprise-post.ts
@@ -69,9 +69,9 @@ export const JiraConnectEnterprisePost = async (
 	// inside the handler
 	const TIMEOUT_PERIOD_MS = parseInt(process.env.JIRA_CONNECT_ENTERPRISE_POST_TIMEOUT_MSEC || "30000");
 
-	const gheServerURL = req.body.gheServerURL?.trim();
-	const apiKeyHeaderName = req.body.apiKeyHeaderName?.trim();
-	const apiKeyValue = req.body.apiKeyValue?.trim();
+	const gheServerURL: string = req.body.gheServerURL?.trim() ?? "undefined";
+	const apiKeyHeaderName: string | undefined = req.body.apiKeyHeaderName?.trim();
+	const apiKeyValue: string | undefined = req.body.apiKeyValue?.trim();
 
 	const { id: installationId } = res.locals.installation;
 
@@ -124,7 +124,7 @@ export const JiraConnectEnterprisePost = async (
 
 	try {
 		const client = await createAnonymousClient(gheServerURL, jiraHost, { trigger: "jira-connect-enterprise-post" }, req.log,
-			apiKeyHeaderName
+			apiKeyHeaderName && apiKeyValue !== undefined
 				? {
 					headerName: apiKeyHeaderName,
 					apiKeyGenerator: () => Promise.resolve(apiKeyValue)
@@ -146,7 +146,7 @@ export const JiraConnectEnterprisePost = async (
 					reason: "Received OK, but the host is not GitHub Enterprise server"
 				}]
 			});
-			sendErrorMetricAndAnalytics(jiraHost, ErrorResponseCode.CANNOT_CONNECT, "" + response.status);
+			sendErrorMetricAndAnalytics(jiraHost, ErrorResponseCode.CANNOT_CONNECT, response?.status?.toString() ?? "undefined");
 			return;
 		}
 
@@ -176,7 +176,7 @@ export const JiraConnectEnterprisePost = async (
 			return;
 		}
 
-		const codeOrStatus = "" + (axiosError.code || axiosError.response?.status);
+		const codeOrStatus = (axiosError.code || axiosError.response?.status?.toString() || "undefined");
 		req.log.warn({ err, gheServerURL }, `Couldn't access GHE host`);
 
 		const reasons = [err.message];
diff --git a/src/routes/jira/connect/jira-connect-get.ts b/src/routes/jira/connect/jira-connect-get.ts
index 1bbd052dba..7c49e96320 100644
--- a/src/routes/jira/connect/jira-connect-get.ts
+++ b/src/routes/jira/connect/jira-connect-get.ts
@@ -1,6 +1,7 @@
 import { NextFunction, Request, Response } from "express";
 import { sendAnalytics } from "utils/analytics-client";
 import { AnalyticsEventTypes, AnalyticsScreenEventsEnum } from "interfaces/common";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 export const JiraConnectGet = async (
 	req: Request,
@@ -19,7 +20,7 @@ export const JiraConnectGet = async (
 		res.render("jira-select-github-product.hbs");
 
 		req.log.info("Jira Connect page rendered successfully.");
-	} catch (error) {
-		return next(new Error(`Failed to render Jira Connect page: ${error}`));
+	} catch (error: unknown) {
+		return next(new Error(`Failed to render Jira Connect page: ${errorStringFromUnknown(error)}`));
 	}
 };
diff --git a/src/routes/jira/jira-connected-repos-get.test.ts b/src/routes/jira/jira-connected-repos-get.test.ts
index 6682da3971..35ba654d90 100644
--- a/src/routes/jira/jira-connected-repos-get.test.ts
+++ b/src/routes/jira/jira-connected-repos-get.test.ts
@@ -105,7 +105,7 @@ describe("jira-connected-repos-get", () => {
 					delete newRepoSyncState["commitStatus"];
 					delete newRepoSyncState["branchStatus"];
 					newRepoSyncState["repoId"] = repoSyncState.repoId + newRepoStateNo;
-					newRepoSyncState["repoName"] = repoSyncState.repoName + newRepoStateNo;
+					newRepoSyncState["repoName"] = repoSyncState.repoName + newRepoStateNo.toString();
 					newRepoSyncState["repoFullName"] = repoSyncState.repoFullName + String(newRepoStateNo).padStart(3, "0");
 					if (newRepoStateNo % 3 == 1) {
 						newRepoSyncState["commitStatus"] = "complete";
diff --git a/src/routes/jira/jira-connected-repos-get.ts b/src/routes/jira/jira-connected-repos-get.ts
index 16950607ec..1c848f1fbd 100644
--- a/src/routes/jira/jira-connected-repos-get.ts
+++ b/src/routes/jira/jira-connected-repos-get.ts
@@ -3,6 +3,7 @@ import { Op } from "sequelize";
 import { RepoSyncState } from "~/src/models/reposyncstate";
 import { Subscription, TaskStatus } from "~/src/models/subscription";
 import { sequelize } from "models/sequelize";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 interface Page {
 	pageNum: number;
@@ -130,9 +131,9 @@ export const JiraConnectedReposGet = async (
 			...getPaginationState(pageNumber, pageSize, reposCount)
 		});
 
-	} catch (err) {
+	} catch (err: unknown) {
 		req.log.warn({ err }, "Failed to render connected repos");
-		return next(new Error(`Failed to render connected repos: ${err}`));
+		return next(new Error(`Failed to render connected repos: ${errorStringFromUnknown(err)}`));
 	}
 };
 
diff --git a/src/routes/jira/jira-delete.test.ts b/src/routes/jira/jira-delete.test.ts
index f00b9f10e1..1885b62c3c 100644
--- a/src/routes/jira/jira-delete.test.ts
+++ b/src/routes/jira/jira-delete.test.ts
@@ -94,11 +94,11 @@ describe("DELETE /jira/configuration", () => {
 			.reply(200, "OK");
 
 		jiraNock
-			.delete("/rest/security/1.0/linkedWorkspaces/bulk?workspaceIds="+subscription.id)
+			.delete("/rest/security/1.0/linkedWorkspaces/bulk?workspaceIds="+(subscription.id ? (subscription.id as number)?.toString() : "undefined"))
 			.reply(202);
 
 		jiraNock
-			.delete("/rest/security/1.0/bulkByProperties?workspaceId="+subscription.id)
+			.delete("/rest/security/1.0/bulkByProperties?workspaceId="+(subscription.id ? (subscription.id as number)?.toString() : "undefined"))
 			.reply(202);
 
 		jiraNock
diff --git a/src/routes/jira/jira-get.ts b/src/routes/jira/jira-get.ts
index d935638edc..82d8a1ab39 100644
--- a/src/routes/jira/jira-get.ts
+++ b/src/routes/jira/jira-get.ts
@@ -13,6 +13,7 @@ import { AnalyticsEventTypes, AnalyticsScreenEventsEnum } from "interfaces/commo
 import { getCloudOrServerFromGitHubAppId } from "utils/get-cloud-or-server";
 import { Errors } from "config/errors";
 import { booleanFlag, BooleanFlags } from "config/feature-flags";
+import { errorStringFromUnknown } from "~/src/util/error-string-from-unknown";
 
 interface FailedConnection {
 	id: number;
@@ -182,7 +183,7 @@ const renderJiraCloudAndEnterpriseServer = async (res: Response, req: Request):
 	}
 
 	const successfulServerConnections = gheServersWithConnections
-		.reduce((acc, obj) => acc + obj.successfulConnections?.length, 0);
+		.reduce((acc: number, obj: any) => acc + (obj.successfulConnections?.length as number), 0);
 	const allSuccessfulConnections = [...successfulCloudConnections, ...gheServersWithConnections];
 	const completeConnections = allSuccessfulConnections.filter(connection => connection.syncStatus === "FINISHED");
 
@@ -232,7 +233,7 @@ export const JiraGet = async (
 
 		await renderJiraCloudAndEnterpriseServer(res, req);
 		req.log.debug("Jira configuration rendered successfully.");
-	} catch (error) {
-		return next(new Error(`Failed to render Jira configuration: ${error}`));
+	} catch (error: unknown) {
+		return next(new Error(`Failed to render Jira configuration: ${errorStringFromUnknown(error)}`));
 	}
 };
diff --git a/src/routes/jira/security/workspaces/jira-security-workspaces-post.test.ts b/src/routes/jira/security/workspaces/jira-security-workspaces-post.test.ts
index 40305233da..9d637448be 100644
--- a/src/routes/jira/security/workspaces/jira-security-workspaces-post.test.ts
+++ b/src/routes/jira/security/workspaces/jira-security-workspaces-post.test.ts
@@ -169,7 +169,7 @@ describe("Workspaces Post", () => {
 				{
 					id: String(createdDbEntries.sub1.id),
 					name: createdDbEntries.repo1.repoOwner,
-					url: "https://github.com/"+ createdDbEntries.repo1.repoOwner,
+					url: "https://github.com/" + (createdDbEntries.repo1.repoOwner as string),
 					avatarUrl: createdDbEntries.sub1.avatarUrl
 				}
 			]
@@ -220,7 +220,7 @@ describe("Workspaces Post", () => {
 				{
 					id: String(createdDbEntries.sub1.id),
 					name: createdDbEntries.repo1.repoOwner,
-					url: "https://github.com/"+ createdDbEntries.repo1.repoOwner,
+					url: "https://github.com/" + (createdDbEntries.repo1.repoOwner as string),
 					avatarUrl: createdDbEntries.sub1.avatarUrl
 				}
 			]
@@ -250,7 +250,7 @@ describe("Workspaces Post", () => {
 				{
 					id: String(createdDbEntries.sub3.id),
 					name: createdDbEntries.repo3.repoOwner,
-					url: "https://github.com/"+ createdDbEntries.repo3.repoOwner,
+					url: "https://github.com/" + (createdDbEntries.repo3.repoOwner as string),
 					avatarUrl: DEFAULT_AVATAR
 				}
 			]
@@ -279,19 +279,19 @@ describe("Workspaces Post", () => {
 				{
 					id: String(createdDbEntries.sub1.id),
 					name: createdDbEntries.repo1.repoOwner,
-					url: "https://github.com/"+ createdDbEntries.repo1.repoOwner,
+					url: "https://github.com/" + (createdDbEntries.repo1.repoOwner as string),
 					avatarUrl: createdDbEntries.sub1.avatarUrl
 				},
 				{
 					id: String(createdDbEntries.sub2.id),
 					name: createdDbEntries.repo2.repoOwner,
-					url: "https://github.internal.atlassian.com/"+ createdDbEntries.repo2.repoOwner,
+					url: "https://github.internal.atlassian.com/" + (createdDbEntries.repo2.repoOwner as string),
 					avatarUrl: createdDbEntries.sub2.avatarUrl
 				},
 				{
 					id: String(createdDbEntries.sub3.id),
 					name: createdDbEntries.repo3.repoOwner,
-					url: "https://github.com/"+ createdDbEntries.repo3.repoOwner,
+					url: "https://github.com/" + (createdDbEntries.repo3.repoOwner as string),
 					avatarUrl: DEFAULT_AVATAR
 				}
 			]
diff --git a/src/routes/version/version-get.ts b/src/routes/version/version-get.ts
index 633692a4e5..eb457839ae 100644
--- a/src/routes/version/version-get.ts
+++ b/src/routes/version/version-get.ts
@@ -4,10 +4,10 @@ import { envVars }  from "config/env";
 export const VersionGet = (_: Request, res: Response) => {
 	res.send({
 		branch: envVars.GIT_BRANCH_NAME,
-		branchUrl: `${envVars.GITHUB_REPO_URL}/tree/${envVars.GIT_BRANCH_NAME}`,
+		branchUrl: `${envVars.GITHUB_REPO_URL}/tree/${envVars.GIT_BRANCH_NAME ?? "undefined"}`,
 		commit: envVars.GIT_COMMIT_SHA,
 		commitDate: envVars.GIT_COMMIT_DATE,
-		commitUrl: `${envVars.GITHUB_REPO_URL}/commit/${envVars.GIT_COMMIT_SHA}`,
+		commitUrl: `${envVars.GITHUB_REPO_URL}/commit/${envVars.GIT_COMMIT_SHA ?? "undefined"}`,
 		deploymentDate: envVars.DEPLOYMENT_DATE
 	});
 };
diff --git a/src/services/subscription-installation-service.test.ts b/src/services/subscription-installation-service.test.ts
index 736db45e03..ed2c656a71 100644
--- a/src/services/subscription-installation-service.test.ts
+++ b/src/services/subscription-installation-service.test.ts
@@ -36,7 +36,7 @@ describe("subscription-installation-service", () => {
 
 		if (config.isInstalledInUserSpace !== undefined) {
 			cloudOrGheNock
-				.get("/app/installations/" + gitHubInstallationId)
+				.get("/app/installations/" + gitHubInstallationId.toString())
 				.matchHeader("Authorization", /^Bearer .+$/)
 				.reply(200, {
 					account: {
@@ -48,7 +48,7 @@ describe("subscription-installation-service", () => {
 
 		if (config.fetchAvatar === true) {
 			cloudOrGheNock
-				.get("/app/installations/" + gitHubInstallationId)
+				.get("/app/installations/" + gitHubInstallationId.toString())
 				.matchHeader("Authorization", /^Bearer .+$/)
 				.reply(200, {
 					account: {
diff --git a/src/sqs/backfill-error-handler.test.ts b/src/sqs/backfill-error-handler.test.ts
index f49e186a30..91a02ae778 100644
--- a/src/sqs/backfill-error-handler.test.ts
+++ b/src/sqs/backfill-error-handler.test.ts
@@ -57,7 +57,7 @@ describe("backfillErrorHandler", () => {
 				"date": "Fri, 04 Mar 2022 21:09:27 GMT",
 				"x-ratelimit-limit": "8900",
 				"x-ratelimit-remaining": "0",
-				"x-ratelimit-reset": "" + resetTime,
+				"x-ratelimit-reset": "" + resetTime.toString(),
 				"x-ratelimit-resource": "core",
 				"x-ratelimit-used": "2421"
 			});
diff --git a/src/sqs/error-handlers.ts b/src/sqs/error-handlers.ts
index 1cb5ab8fac..aa5bfa9b95 100644
--- a/src/sqs/error-handlers.ts
+++ b/src/sqs/error-handlers.ts
@@ -1,5 +1,4 @@
 import { JiraClientError } from "../jira/client/axios";
-import { Octokit } from "@octokit/rest";
 import { emitWebhookFailedMetrics } from "utils/webhook-utils";
 import { ErrorHandler, ErrorHandlingResult, SQSMessageContext, BaseMessagePayload } from "./sqs.types";
 import { GithubClientRateLimitingError } from "../github/client/github-client-errors";
@@ -18,10 +17,8 @@ const RATE_LIMITING_DELAY_BUFFER_SEC = 10;
 const EXPONENTIAL_BACKOFF_BASE_SEC = 60;
 const EXPONENTIAL_BACKOFF_MULTIPLIER = 3;
 
-type ErrorTypes = JiraClientError | Octokit.HookError | GithubClientRateLimitingError | Error;
-
 export const handleUnknownError: ErrorHandler<BaseMessagePayload> = async <MessagePayload extends BaseMessagePayload>(
-	err: ErrorTypes,
+	err: Error,
 	context: SQSMessageContext<MessagePayload>
 ): Promise<ErrorHandlingResult> => {
 	const delaySec = EXPONENTIAL_BACKOFF_BASE_SEC * Math.pow(EXPONENTIAL_BACKOFF_MULTIPLIER, context.receiveCount);
@@ -29,7 +26,7 @@ export const handleUnknownError: ErrorHandler<BaseMessagePayload> = async <Messa
 	return { retryable: true, retryDelaySec: delaySec, isFailure: true };
 };
 
-export const jiraAndGitHubErrorsHandler: ErrorHandler<BaseMessagePayload> = async <MessagePayload extends BaseMessagePayload> (error: ErrorTypes,
+export const jiraAndGitHubErrorsHandler: ErrorHandler<BaseMessagePayload> = async <MessagePayload extends BaseMessagePayload> (error: Error,
 	context: SQSMessageContext<MessagePayload>): Promise<ErrorHandlingResult> => {
 
 	context.log.warn({ err: error }, "Handling Jira or GitHub error");
@@ -78,9 +75,9 @@ const maybeHandleNonRetryableResponseCode = <MessagePayload extends BaseMessageP
 	//Unfortunately we can't check if error is instance of Octokit.HookError because it is not a class, so we'll just rely on status
 	//New GitHub Client error (GithubClientError) also has status parameter, so it will be covered by the following check too
 	//TODO When we get rid of Octokit completely add check if (error instanceof GithubClientError) before the following code
-	const maybeErrorWithStatus: any = error;
-	if (maybeErrorWithStatus.status && UNRETRYABLE_STATUS_CODES.includes(maybeErrorWithStatus.status)) {
-		context.log.warn({ err: maybeErrorWithStatus }, `Received error with ${maybeErrorWithStatus.status} status. Unretryable. Discarding the message`);
+	const status: number | undefined = error["status"];
+	if (status && UNRETRYABLE_STATUS_CODES.includes(status)) {
+		context.log.warn({ err: error }, `Received error with ${status} status. Unretryable. Discarding the message`);
 		return { retryable: false, isFailure: false };
 	}
 	return undefined;
diff --git a/src/sqs/sqs.ts b/src/sqs/sqs.ts
index b31395e040..7babb7a99d 100644
--- a/src/sqs/sqs.ts
+++ b/src/sqs/sqs.ts
@@ -82,7 +82,7 @@ export class SqsQueue<MessagePayload extends BaseMessagePayload> {
 
 		const sendMessageResult = await this.sqs.sendMessage(params)
 			.promise();
-		logger.info({ delaySeconds: delaySec, newMessageId: sendMessageResult.MessageId }, `Successfully added message to sqs queue messageId: ${sendMessageResult.MessageId}`);
+		logger.info({ delaySeconds: delaySec, newMessageId: sendMessageResult.MessageId }, `Successfully added message to sqs queue messageId: ${sendMessageResult.MessageId ?? "undefinded"}`);
 		statsd.increment(sqsQueueMetrics.sent, this.metricsTags, { jiraHost: payload.jiraHost });
 		return sendMessageResult;
 	}
@@ -382,7 +382,7 @@ export class SqsQueue<MessagePayload extends BaseMessagePayload> {
 
 	public async changeVisibilityTimeout(message: Message, timeoutSec: number, logger: Logger): Promise<void> {
 		if (!message.ReceiptHandle) {
-			logger.error(`No ReceiptHandle in message with ID = ${message.MessageId}`);
+			logger.error(`No ReceiptHandle in message with ID = ${message.MessageId ?? ""}`);
 			return;
 		}
 
diff --git a/src/sync/branches.ts b/src/sync/branches.ts
index 43e6a3b72d..3d4230cefc 100644
--- a/src/sync/branches.ts
+++ b/src/sync/branches.ts
@@ -5,6 +5,7 @@ import Logger from "bunyan";
 import { BackfillMessagePayload } from "~/src/sqs/sqs.types";
 import { createHashWithSharedSecret } from "utils/encryption";
 import { shouldSendAll } from "config/feature-flags";
+import { Branch } from "~/src/github/client/github-client.types";
 
 // TODO: better typings
 export const getBranchTask = async (
@@ -24,7 +25,7 @@ export const getBranchTask = async (
 	const commitSince = messagePayload.commitsFromDate ? new Date(messagePayload.commitsFromDate) : undefined;
 	const result = await gitHubClient.getBranchesPage(repository.owner.login, repository.name, perPage, commitSince, cursor as string);
 	const edges = result?.repository?.refs?.edges || [];
-	const branches = edges.map(edge => edge?.node);
+	const branches: Branch[] = edges.map(edge => edge?.node);
 	(logger.fields || {}).branchNameArray = (branches || []).map(b => createHashWithSharedSecret(String(b.name)));
 	(logger.fields || {}).branchShaArray = (branches || []).map(b => createHashWithSharedSecret(String(b.target?.oid)));
 	const alwaysSendBranches = await shouldSendAll("branches-backfill", _jiraHost, logger);
diff --git a/src/sync/code-scanning-alerts.ts b/src/sync/code-scanning-alerts.ts
index 734eba3bf1..0b64a08ebb 100644
--- a/src/sync/code-scanning-alerts.ts
+++ b/src/sync/code-scanning-alerts.ts
@@ -85,8 +85,8 @@ const transformCodeScanningAlert = async (
 
 	const gitHubClientConfig = await getGitHubClientConfigFromAppId(gitHubAppId, jiraHost);
 
-	const handleUnmappedState = (state) => logger.info(`Received unmapped state from code_scanning_alert sync: ${state}`);
-	const handleUnmappedSeverity = (severity) => logger.info(`Received unmapped severity from code_scanning_alert sync: ${severity}`);
+	const handleUnmappedState = (state: string) => logger.info(`Received unmapped state from code_scanning_alert sync: ${state}`);
+	const handleUnmappedSeverity = (severity: string | null) => logger.info(`Received unmapped severity from code_scanning_alert sync: ${severity ?? "Missing Severity"}`);
 
 	const vulnerabilities = alerts.map((alert) => {
 		const identifiers = transformRuleTagsToIdentifiers(alert.rule.tags);
diff --git a/src/sync/commits.ts b/src/sync/commits.ts
index 97b359b8ad..bc0caefd05 100644
--- a/src/sync/commits.ts
+++ b/src/sync/commits.ts
@@ -38,7 +38,8 @@ export const getCommitTask = async (
 	const { edges, commits } = await fetchCommits(gitHubClient, repository, commitSince, cursor, perPage);
 
 	if (commits.length > 0) {
-		logger.info(`Last commit authoredDate=${commits[commits.length - 1].authoredDate}`);
+		const authoredDate = commits[commits.length - 1]?.authoredDate;
+		logger.info(`Last commit authoredDate=${authoredDate?.toString() || "undefined"}`);
 		(logger.fields || {}).commitShaArray = commits.map(c => createHashWithSharedSecret(String(c.oid)));
 	}
 	const alwaysSend = await shouldSendAll("commits-backfill", _jiraHost, logger);
diff --git a/src/sync/deduplicator.test.ts b/src/sync/deduplicator.test.ts
index f17f37674d..3ebb650ca6 100644
--- a/src/sync/deduplicator.test.ts
+++ b/src/sync/deduplicator.test.ts
@@ -8,7 +8,7 @@ describe("deduplicator", () => {
 	let key = "";
 	beforeEach(() => {
 		storage = new RedisInProgressStorageWithTimeout(redis);
-		key = new Date().toISOString() + Math.random();
+		key = new Date().toISOString() + Math.random().toString();
 		jest.useFakeTimers("modern").setSystemTime(new Date("2020-01-01").getTime());
 	});
 
diff --git a/src/sync/dependabot-alerts.ts b/src/sync/dependabot-alerts.ts
index fcdb082103..e135edf142 100644
--- a/src/sync/dependabot-alerts.ts
+++ b/src/sync/dependabot-alerts.ts
@@ -86,8 +86,8 @@ const transformDependabotAlerts = async (
 
 	const gitHubClientConfig = await getGitHubClientConfigFromAppId(gitHubAppId, jiraHost);
 
-	const handleUnmappedState = (state) => logger.info(`Received unmapped state from dependabot_alerts sync: ${state}`);
-	const handleUnmappedSeverity = (severity) => logger.info(`Received unmapped severity from dependabot_alerts sync: ${severity}`);
+	const handleUnmappedState = (state: string) => logger.info(`Received unmapped state from dependabot_alerts sync: ${state}`);
+	const handleUnmappedSeverity = (severity: string | null) => logger.info(`Received unmapped severity from dependabot_alerts sync: ${severity ?? "Missing Severity"}`);
 
 	const vulnerabilities = alerts.map((alert) => {
 		return {
diff --git a/src/sync/deployment.test.ts b/src/sync/deployment.test.ts
index 8e7a8a9fe6..5bb1f79ad6 100644
--- a/src/sync/deployment.test.ts
+++ b/src/sync/deployment.test.ts
@@ -10,7 +10,7 @@ import { envVars } from "config/env";
 
 import deploymentNodesFixture from "fixtures/api/graphql/deployment-nodes.json";
 import mixedDeploymentNodes from "fixtures/api/graphql/deployment-nodes-mixed.json";
-import { getDeploymentsQuery, getDeploymentsQueryWithStatuses } from "~/src/github/client/github-queries";
+import { DeploymentQueryNode, getDeploymentsQuery, getDeploymentsQueryWithStatuses } from "~/src/github/client/github-queries";
 import { waitUntil } from "test/utils/wait-until";
 import { DatabaseStateCreator } from "test/utils/database-state-creator";
 import { GitHubServerApp } from "models/github-server-app";
@@ -209,16 +209,15 @@ describe("sync/deployments", () => {
 		//size up to 9 entities
 		const createDeploymentEntities = (size: number) => {
 			return Array.from({ length: size }).map((_, idx) => {
-				const clone = JSON.parse(JSON.stringify(deploymentNodesFixture.data.repository.deployments.edges[0]));
-				clone._seq = idx + 1;
-				clone.cursor = `cursor:${idx + 1}`;
+				const clone: DeploymentQueryNode = JSON.parse(JSON.stringify(deploymentNodesFixture.data.repository.deployments.edges[0]));
+				clone.cursor = `${idx + 1}`;
 				clone.node.createdAt = `2023-01-0${idx + 1}T10:00:00Z`;
 				clone.node.updatedAt = `2023-01-0${idx + 1}T10:00:00Z`;
 				clone.node.databaseId = `dbid-${idx + 1}`;
 				clone.node.commitOid = `SHA${idx + 1}`;
-				clone.node.statuses.nodes.forEach(n => {
+				clone.node.statuses!.nodes.forEach(n => {
 					n.createdAt = clone.node.createdAt;
-					n.updatedAt = clone.node.updatedAt;
+					n.updatedAt = clone.node.updatedAt!;
 					if (n.state === "SUCCESS") {
 						n.logUrl = `deployment-url-${idx + 1}`;
 					}
@@ -232,10 +231,10 @@ describe("sync/deployments", () => {
 				.query(true).reply(200, { data: { repository: { deployments: { edges: deployments } } } });
 		};
 
-		const nockDeploymentListingApi = (deployments, repeatTimes) => {
+		const nockDeploymentListingApi = (deployments: DeploymentQueryNode[], repeatTimes: number) => {
 			Array.from({ length: repeatTimes }).forEach(() => {
 				githubNock.get(`/repos/test-repo-owner/test-repo-name/deployments?environment=prod&per_page=10`)
-					.reply(200, deployments.map((item, idx) => ({
+					.reply(200, deployments.map((item: DeploymentQueryNode, idx: number) => ({
 						id: item.node.databaseId,
 						sha: item.node.commitOid,
 						ref: "random",
@@ -255,7 +254,7 @@ describe("sync/deployments", () => {
 			});
 		};
 
-		const nockDeploymentStatusApi = (deployments, repeatTimes) => {
+		const nockDeploymentStatusApi = (deployments: DeploymentQueryNode[], repeatTimes: number) => {
 			Array.from({ length: repeatTimes }).forEach(() => {
 				deployments.forEach((item, idx) => {
 					githubNock.get(`/repos/test-repo-owner/test-repo-name/deployments/${item.node.databaseId}/statuses?per_page=100`)
@@ -267,25 +266,25 @@ describe("sync/deployments", () => {
 			});
 		};
 
-		const nockDeploymentCommitGetApi = (deployments, repeatTimes) => {
+		const nockDeploymentCommitGetApi = (deployments: DeploymentQueryNode[], repeatTimes: number) => {
 			Array.from({ length: repeatTimes }).forEach(() => {
 				deployments.forEach(item => {
 					githubNock.get(`/repos/test-repo-owner/test-repo-name/commits/${item.node.commitOid}`)
 						.reply(200, {
 							commit: {
 								author: { name: "random", email: "random", date: new Date() },
-								message: `commit message [JIRA-${item._seq}]`
+								message: `commit message [JIRA-${item.cursor}]`
 							}, html_url: "random"
 						});
 				});
 			});
 		};
 
-		const expectDeploymentEntryInDB = async (deployments) => {
+		const expectDeploymentEntryInDB = async (deployments: DeploymentQueryNode[]) => {
 			for (const deployment of deployments) {
 				const { repository: { id: repoId }, environment, statuses, commitOid } = deployment.node;
 				const key = createHashWithoutSharedSecret(`ghurl_${gitHubCloudConfig.baseUrl}_repo_${repoId}_env_${environment}`);
-				const successStatusDate = new Date(statuses.nodes.find(n=>n.state === "SUCCESS")?.updatedAt).getTime();
+				const successStatusDate = new Date(statuses!.nodes.find(n=>n.state === "SUCCESS")!.updatedAt).getTime();
 				const result = await ddb.getItem({
 					TableName: envVars.DYNAMO_DEPLOYMENT_HISTORY_CACHE_TABLE_NAME,
 					Key: {
@@ -299,14 +298,14 @@ describe("sync/deployments", () => {
 			}
 		};
 
-		const expectEdgesAndPayloadMatchToDeploymentCommits = (result, deployments) => {
+		const expectEdgesAndPayloadMatchToDeploymentCommits = (result, deployments: DeploymentQueryNode[]) => {
 			expect(result).toEqual({
 				edges: deployments.map(d =>
 					expect.objectContaining({ cursor: d.cursor, node: expect.objectContaining({ commitOid: d.node.commitOid }) })
 				),
 				jiraPayload: {
 					deployments: deployments.map(d => expect.objectContaining({
-						associations: [{ associationType: "issueIdOrKeys", values: [ `JIRA-${d._seq}`] }] })
+						associations: [{ associationType: "issueIdOrKeys", values: [ `JIRA-${d.cursor}`] }] })
 					)
 				}
 			});
diff --git a/src/sync/installation.test.ts b/src/sync/installation.test.ts
index ee607d3c90..e6628237e9 100644
--- a/src/sync/installation.test.ts
+++ b/src/sync/installation.test.ts
@@ -354,7 +354,7 @@ describe("sync/installation", () => {
 			const sendMessageMock = jest.fn();
 			await markCurrentTaskAsFailedAndContinue({
 				...MESSAGE_PAYLOAD,
-				installationId: MESSAGE_PAYLOAD.installationId + 1
+				installationId: (MESSAGE_PAYLOAD.installationId as number) + 1
 			}, TASK, false, sendMessageMock, getLogger("test"), mockError);
 
 			const refreshedRepoSyncState = await RepoSyncState.findByPk(repoSyncState.id);
diff --git a/src/sync/parallel-page-fetcher.test.ts b/src/sync/parallel-page-fetcher.test.ts
index 34d856d7ef..6ffbe906fb 100644
--- a/src/sync/parallel-page-fetcher.test.ts
+++ b/src/sync/parallel-page-fetcher.test.ts
@@ -7,11 +7,11 @@ describe("fetchNextPagesInParallel", () => {
 		const singlePageFetchFactory = jest.fn().mockImplementation((pageCursor: PageSizeAwareCounterCursor) => {
 			const edges = [{
 				cursor: pageCursor.serialise(),
-				node: { id: "id" + pageCursor.pageNo }
+				node: { id: "id" + pageCursor.pageNo.toString() }
 			}];
 			const jiraPayload = {
-				pullRequests: [{ id: "pid" + pageCursor.pageNo }],
-				builds: [{ id: "bid" + pageCursor.pageNo }]
+				pullRequests: [{ id: "pid" + pageCursor.pageNo.toString() }],
+				builds: [{ id: "bid" + pageCursor.pageNo.toString() }]
 			};
 			return Promise.resolve({ edges, jiraPayload });
 		});
@@ -33,12 +33,12 @@ describe("fetchNextPagesInParallel", () => {
 		const singlePageFetchFactory = jest.fn().mockImplementation((pageCursor: PageSizeAwareCounterCursor) => {
 			const edges = [{
 				cursor: pageCursor.serialise(),
-				node: { id: "id" + pageCursor.pageNo }
+				node: { id: "id" + pageCursor.pageNo.toString() }
 			}];
 			const jiraPayload = {
 				foo: "bar",
-				pullRequests: [{ id: "pid" + pageCursor.pageNo }],
-				builds: [{ id: "bid" + pageCursor.pageNo }]
+				pullRequests: [{ id: "pid" + pageCursor.pageNo.toString() }],
+				builds: [{ id: "bid" + pageCursor.pageNo.toString() }]
 			};
 			return Promise.resolve({ edges, jiraPayload });
 		});
@@ -65,9 +65,9 @@ describe("fetchNextPagesInParallel", () => {
 			}
 			const edges = [{
 				cursor: pageCursor.serialise(),
-				node: { id: "id" + pageCursor.pageNo }
+				node: { id: "id" + pageCursor.pageNo.toString() }
 			}];
-			const jiraPayload = { pullRequests: [{ id: "pid" + pageCursor.pageNo }] };
+			const jiraPayload = { pullRequests: [{ id: "pid" + pageCursor.pageNo.toString() }] };
 			return Promise.resolve({ edges, jiraPayload });
 		});
 		const fetchedData = await fetchNextPagesInParallel(2, new PageSizeAwareCounterCursor("1"), singlePageFetchFactory);
@@ -86,9 +86,9 @@ describe("fetchNextPagesInParallel", () => {
 			}
 			const edges = [{
 				cursor: pageCursor.serialise(),
-				node: { id: "id" + pageCursor.pageNo }
+				node: { id: "id" + pageCursor.pageNo.toString() }
 			}];
-			const jiraPayload = { pullRequests: [{ id: "pid" + pageCursor.pageNo }] };
+			const jiraPayload = { pullRequests: [{ id: "pid" + pageCursor.pageNo.toString() }] };
 			return Promise.resolve({ edges, jiraPayload });
 		});
 		await expect(fetchNextPagesInParallel(2, new PageSizeAwareCounterCursor("1"), singlePageFetchFactory)).rejects.toThrowError("foo");
diff --git a/src/sync/scheduler.test.ts b/src/sync/scheduler.test.ts
index cfdd473030..85487cb4a4 100644
--- a/src/sync/scheduler.test.ts
+++ b/src/sync/scheduler.test.ts
@@ -22,8 +22,8 @@ describe("scheduler", () => {
 			delete newRepoSyncState["commitStatus"];
 			delete newRepoSyncState["branchStatus"];
 			newRepoSyncState["repoId"] = repoSyncState.repoId + newRepoStateNo;
-			newRepoSyncState["repoName"] = repoSyncState.repoName + newRepoStateNo;
-			newRepoSyncState["repoFullName"] = repoSyncState.repoFullName + newRepoStateNo;
+			newRepoSyncState["repoName"] = repoSyncState.repoName + newRepoStateNo.toString();
+			newRepoSyncState["repoFullName"] = repoSyncState.repoFullName + newRepoStateNo.toString();
 			newRepoSyncStatesData.push(newRepoSyncState);
 		}
 		await RepoSyncState.bulkCreate(newRepoSyncStatesData);
@@ -158,9 +158,9 @@ describe("scheduler", () => {
 		const tasks = await getNextTasks(subscription, [], getLogger("test"));
 		const repoIdsAndTaskType = new Set<string>();
 		tasks.otherTasks.forEach(task => {
-			repoIdsAndTaskType.add("" + task.repositoryId + task.task);
+			repoIdsAndTaskType.add("" + task.repositoryId.toString() + task.task);
 		});
-		repoIdsAndTaskType.add("" + tasks.mainTask!.repositoryId + tasks.mainTask!.task);
+		repoIdsAndTaskType.add("" + tasks.mainTask!.repositoryId.toString() + tasks.mainTask!.task);
 		expect(tasks.otherTasks.length + 1).toEqual(repoIdsAndTaskType.size);
 	});
 
@@ -172,7 +172,7 @@ describe("scheduler", () => {
 		for (let i = 0; i < 50; i++) {
 			const tasks = await getNextTasks(subscription, [], getLogger("test"));
 			tasks.otherTasks.forEach(task => {
-				otherTasksAndTaskTypes.add("" + task.repositoryId);
+				otherTasksAndTaskTypes.add("" + task.repositoryId.toString());
 			});
 		}
 		// The pool size should be 100:
diff --git a/src/sync/transforms/branch.ts b/src/sync/transforms/branch.ts
index f43ebe0634..e6e9fae621 100644
--- a/src/sync/transforms/branch.ts
+++ b/src/sync/transforms/branch.ts
@@ -3,6 +3,8 @@ import { getJiraAuthor, jiraIssueKeyParser, limitCommitMessage } from "utils/jir
 import { isEmpty, union } from "lodash";
 import { generateCreatePullRequestUrl } from "../../transforms/util/pull-request-link-generator";
 import { transformRepositoryDevInfoBulk } from "~/src/transforms/transform-repository";
+import { Repository } from "models/subscription";
+import { Branch } from "~/src/github/client/github-client.types";
 
 // TODO: better typing in file
 /**
@@ -14,7 +16,7 @@ import { transformRepositoryDevInfoBulk } from "~/src/transforms/transform-repos
  *  - Title of the last associated Pull Request
  *  - Message from the last commit in that branch
  */
-const mapBranch = (branch, repository, alwaysSend: boolean) => {
+const mapBranch = (branch: Branch, repository: Repository, alwaysSend: boolean) => {
 	const branchKeys = jiraIssueKeyParser(branch.name);
 	const pullRequestKeys = jiraIssueKeyParser(
 		branch.associatedPullRequests.nodes.length ? branch.associatedPullRequests.nodes[0].title : ""
@@ -83,7 +85,7 @@ const mapCommit = (commit, alwaysSend: boolean) => {
  * @param payload
  * @param gitHubBaseUrl - can be undefined for Cloud
  */
-export const transformBranches = (payload: { branches: any, repository: any }, gitHubBaseUrl: string | undefined, alwaysSendBranches: boolean, alwaysSendCommits: boolean) => {
+export const transformBranches = (payload: { branches: any, repository: Repository }, gitHubBaseUrl: string | undefined, alwaysSendBranches: boolean, alwaysSendCommits: boolean) => {
 	// TODO: use reduce instead of map/filter
 	const branches = payload.branches
 		.map((branch) => mapBranch(branch, payload.repository, alwaysSendBranches))
diff --git a/src/transforms/push.ts b/src/transforms/push.ts
index d01a390aae..7234b75ba9 100644
--- a/src/transforms/push.ts
+++ b/src/transforms/push.ts
@@ -32,7 +32,7 @@ const mapFile = (
 		unchanged: JiraCommitFileChangeTypeEnum.UNKNOWN
 	};
 
-	const fallbackUrl = `https://github.com/${repoOwner}/${repoName}/blob/${commitHash}/${githubFile.filename}`;
+	const fallbackUrl = `https://github.com/${repoOwner ?? "undefined"}/${repoName}/blob/${commitHash}/${githubFile.filename}`;
 
 	if (isEmpty(githubFile.filename)) {
 		return undefined;
diff --git a/src/transforms/transform-code-scanning-alert.ts b/src/transforms/transform-code-scanning-alert.ts
index dbfe451aa2..2b5eb28e2c 100644
--- a/src/transforms/transform-code-scanning-alert.ts
+++ b/src/transforms/transform-code-scanning-alert.ts
@@ -91,9 +91,9 @@ export const transformCodeScanningAlert = async (context: WebhookContext, github
 	return {
 		remoteLinks: [{
 			schemaVersion: "1.0",
-			id: `${transformRepositoryId(repository.id, gitHubInstallationClient.baseUrl)}-${alert.number}`,
+			id: `${transformRepositoryId(repository.id, gitHubInstallationClient.baseUrl)}-${alert.number as number}`,
 			updateSequenceNumber: Date.now(),
-			displayName: `Alert #${alert.number}`,
+			displayName: `Alert #${alert.number as number}`,
 			description: alert.rule.description.substring(0, MAX_STRING_LENGTH) || undefined,
 			url: alert.html_url,
 			type: "security",
@@ -124,15 +124,15 @@ export const transformCodeScanningAlertToJiraSecurity = async (context: WebhookC
 	};
 	const gitHubInstallationClient = await createInstallationClient(githubInstallationId, jiraHost, metrics, context.log, context.gitHubAppConfig?.gitHubAppId);
 
-	const handleUnmappedState = (state) => context.log.info(`Received unmapped state from code_scanning_alert webhook: ${state}`);
-	const handleUnmappedSeverity = (severity) => context.log.info(`Received unmapped severity from code_scanning_alert webhook: ${severity}`);
+	const handleUnmappedState = (state: string) => context.log.info(`Received unmapped state from code_scanning_alert webhook: ${state}`);
+	const handleUnmappedSeverity = (severity: string | null) => context.log.info(`Received unmapped severity from code_scanning_alert webhook: ${severity ?? "Missing Severity"}`);
 
 	const identifiers = transformRuleTagsToIdentifiers(alert.rule.tags);
 
 	return {
 		vulnerabilities: [{
 			schemaVersion: "1.0",
-			id: `c-${transformRepositoryId(repository.id, gitHubInstallationClient.baseUrl)}-${alert.number}`,
+			id: `c-${transformRepositoryId(repository.id, gitHubInstallationClient.baseUrl)}-${alert.number as number}`,
 			updateSequenceNumber: Date.now(),
 			containerId: transformRepositoryId(repository.id, gitHubInstallationClient.baseUrl),
 			displayName: alert.rule.name,
diff --git a/src/transforms/transform-dependabot-alert.ts b/src/transforms/transform-dependabot-alert.ts
index 71f6505223..00cd9859ab 100644
--- a/src/transforms/transform-dependabot-alert.ts
+++ b/src/transforms/transform-dependabot-alert.ts
@@ -34,8 +34,8 @@ export const transformDependabotAlert = async (context: WebhookContext<Dependabo
 
 	const githubClientConfig = await getGitHubClientConfigFromAppId(context.gitHubAppConfig?.gitHubAppId, jiraHost);
 
-	const handleUnmappedState = (state) => context.log.info(`Received unmapped state from dependabot_alert webhook: ${state}`);
-	const handleUnmappedSeverity = (severity) => context.log.info(`Received unmapped severity from dependabot_alert webhook: ${severity}`);
+	const handleUnmappedState = (state: string) => context.log.info(`Received unmapped state from dependabot_alert webhook: ${state}`);
+	const handleUnmappedSeverity = (severity: string | null) => context.log.info(`Received unmapped severity from dependabot_alert webhook: ${severity ?? "Missing Serverity"}`);
 
 	return {
 		vulnerabilities: [{
diff --git a/src/transforms/transform-deployment.test.ts b/src/transforms/transform-deployment.test.ts
index f21842cf5d..7cff9ee74b 100644
--- a/src/transforms/transform-deployment.test.ts
+++ b/src/transforms/transform-deployment.test.ts
@@ -288,7 +288,7 @@ describe("transform GitHub webhook payload to Jira payload", () => {
 				]);
 
 			// Compare commits
-			githubNock.get(`/repos/${owner.login}/${repoName}/compare/6e87a40179eb7ecf5094b9c8d690db727472d5bc...${deploymentPayload.deployment.sha}`)
+			githubNock.get(`/repos/${owner.login}/${repoName}/compare/6e87a40179eb7ecf5094b9c8d690db727472d5bc...${deploymentPayload.deployment.sha as string}`)
 				.reply(200, { commits: [] });
 
 			mockGetRepoConfigNoServices();
@@ -697,7 +697,7 @@ describe("transform GitHub webhook payload to Jira payload", () => {
 				const jiraPayload = await transformDeployment(gitHubClient, deployment_status.payload as any, jiraHost, "webhook", getLogger("deploymentLogger"), undefined);
 
 				// make expected issue id array
-				const expectedIssueIds = [...Array(500).keys()].map(number => "ABC-" + (number + 1));
+				const expectedIssueIds = [...Array(500).keys()].map(number => "ABC-" + (number + 1).toString());
 
 				expect(jiraPayload).toMatchObject(buildJiraPayload("testing", [
 					{
@@ -733,7 +733,7 @@ describe("transform GitHub webhook payload to Jira payload", () => {
 				expect(jiraPayload).toMatchObject(buildJiraPayload("testing", [
 					{
 						associationType: "issueIdOrKeys",
-						values: [...Array(499).keys()].map(number => "ABC-" + (number + 1))
+						values: [...Array(499).keys()].map(number => "ABC-" + (number + 1).toString())
 					},
 					{
 						associationType: "serviceIdOrKeys",
@@ -779,7 +779,7 @@ describe("transform GitHub webhook payload to Jira payload", () => {
 				expect(jiraPayload).toMatchObject(buildJiraPayload("testing", [
 					{
 						associationType: "issueIdOrKeys",
-						values: [...Array(497).keys()].map(number => "ABC-" + (number + 1))
+						values: [...Array(497).keys()].map(number => "ABC-" + (number + 1).toString())
 					},
 					{
 						associationType: "serviceIdOrKeys",
diff --git a/src/transforms/transform-pull-request.ts b/src/transforms/transform-pull-request.ts
index 66eac1642d..9f7b5fa241 100644
--- a/src/transforms/transform-pull-request.ts
+++ b/src/transforms/transform-pull-request.ts
@@ -96,7 +96,7 @@ export const extractIssueKeysFromPrRest = async (pullRequest: Octokit.PullsListR
 
 export const extractIssueKeysFromPr = (pullRequest: pullRequestNode) => {
 	const { title, headRef, body } = pullRequest;
-	return jiraIssueKeyParser(`${title}\n${headRef?.name}\n${body}`);
+	return jiraIssueKeyParser(`${title}\n${headRef?.name ?? ""}\n${body}`);
 };
 
 export const transformPullRequestRest = async (
diff --git a/src/transforms/transform-repository-id.ts b/src/transforms/transform-repository-id.ts
index 82d1fd01f4..7c5d30ccb5 100644
--- a/src/transforms/transform-repository-id.ts
+++ b/src/transforms/transform-repository-id.ts
@@ -31,7 +31,7 @@ const calculatePrefix = (url: string) => {
  */
 export const transformRepositoryId = (repositoryId: number, gitHubBaseUrl?: string): TransformedRepositoryId => {
 	if (!gitHubBaseUrl || calculatePrefix(gitHubBaseUrl) === calculatePrefix(GITHUB_CLOUD_BASEURL)) {
-		return ("" + repositoryId) as TransformedRepositoryId;
+		return (repositoryId?.toString() || "undefined") as TransformedRepositoryId;
 	}
 
 	return `${calculatePrefix(gitHubBaseUrl)}-${repositoryId}` as TransformedRepositoryId;
diff --git a/src/transforms/transform-secret-scanning-alert.ts b/src/transforms/transform-secret-scanning-alert.ts
index 708ecc7e32..e5ddbd6b68 100644
--- a/src/transforms/transform-secret-scanning-alert.ts
+++ b/src/transforms/transform-secret-scanning-alert.ts
@@ -44,7 +44,7 @@ export const transformSecretScanningAlert = async (
 // To Jira: Status can be one of: : open, closed
 export const transformGitHubStateToJiraStatus = (state: string | undefined, logger: Logger): JiraVulnerabilityStatusEnum => {
 	if (!state) {
-		logger.info(`Received unmapped state from secret_scanning_alert webhook: ${state}`);
+		logger.info(`Received unmapped state from secret_scanning_alert webhook: ${state ?? "Missing State"}`);
 		return JiraVulnerabilityStatusEnum.UNKNOWN;
 	}
 	switch (state) {
diff --git a/src/transforms/transform-workflow.ts b/src/transforms/transform-workflow.ts
index 1ca3251692..cbdfb674c1 100644
--- a/src/transforms/transform-workflow.ts
+++ b/src/transforms/transform-workflow.ts
@@ -83,7 +83,7 @@ export const transformWorkflow = async (
 		logger
 	) : "";
 
-	const issueKeys = jiraIssueKeyParser(`${head_branch}\n${payload.workflow_run.head_commit?.message}\n${commitMessages}`);
+	const issueKeys = jiraIssueKeyParser(`${head_branch}\n${payload.workflow_run.head_commit?.message ?? ""}\n${commitMessages}`);
 	if (!issueKeys.length && !alwaysSend) {
 		return undefined;
 	}
diff --git a/src/util/create-url-with-query-string.ts b/src/util/create-url-with-query-string.ts
index 6ef3e879eb..b849fd46f0 100644
--- a/src/util/create-url-with-query-string.ts
+++ b/src/util/create-url-with-query-string.ts
@@ -13,7 +13,8 @@ export const createUrlWithQueryString = (req: Request, URL: string): string => {
 	const queryStrings = keys.reduce((_, current, index, array) => {
 		if (req.query[current]) {
 			queryString += index === 0 ? "?" : "";
-			queryString += current + "=" + req.query[current];
+			queryString += current + "=";
+			queryString += req.query[current];
 			queryString += index !== array.length - 1 ? "&" : "";
 		}
 		return queryString;
diff --git a/src/util/curl/curl-utils.test.ts b/src/util/curl/curl-utils.test.ts
index f2dab93496..769dfc26e6 100644
--- a/src/util/curl/curl-utils.test.ts
+++ b/src/util/curl/curl-utils.test.ts
@@ -35,7 +35,7 @@ describe("curl-utils", () => {
 
 	describe("logCurlOutput", () => {
 		it("should not explode with empty output", () => {
-			logCurlOutputInChunks({ body: "", meta: "" }, getLogger("test"));
+			expect(() => logCurlOutputInChunks({ body: "", meta: "" }, getLogger("test"))).not.toThrowError();
 		});
 
 		it("should not explode with non-empty output", async () => {
@@ -44,7 +44,7 @@ describe("curl-utils", () => {
 				method: "GET",
 				authorization: "secrets"
 			});
-			logCurlOutputInChunks(result, getLogger("test"));
+			expect(() => logCurlOutputInChunks(result, getLogger("test"))).not.toThrowError();
 		});
 	});
 });
diff --git a/src/util/error-string-from-unknown.ts b/src/util/error-string-from-unknown.ts
new file mode 100644
index 0000000000..0dbb2e9185
--- /dev/null
+++ b/src/util/error-string-from-unknown.ts
@@ -0,0 +1,3 @@
+export const errorStringFromUnknown = (e : unknown) : string => {
+	return e instanceof Error ? e.toString() : "unkown";
+};
diff --git a/src/util/handlebars/handlebar-helpers.ts b/src/util/handlebars/handlebar-helpers.ts
index f159d0347a..ecd849abc7 100644
--- a/src/util/handlebars/handlebar-helpers.ts
+++ b/src/util/handlebars/handlebar-helpers.ts
@@ -21,7 +21,7 @@ export const registerHandlebarsHelpers = () => {
 
 	hbs.registerHelper(
 		"ifAllReposSynced",
-		(numberOfSyncedRepos, totalNumberOfRepos) =>
+		(numberOfSyncedRepos: number, totalNumberOfRepos: number): any =>
 			numberOfSyncedRepos === totalNumberOfRepos
 				? totalNumberOfRepos
 				: `${numberOfSyncedRepos} / ${totalNumberOfRepos}`
@@ -33,7 +33,7 @@ export const registerHandlebarsHelpers = () => {
 
 	hbs.registerHelper("isNotConnected", (syncStatus) => syncStatus == null);
 
-	hbs.registerHelper("setSubscriptionUrl", (uuid, installationId) => uuid
+	hbs.registerHelper("setSubscriptionUrl", (uuid: string, installationId: number) => uuid
 		? `/github/${uuid}/subscriptions/${installationId}`
 		: `/github/subscriptions/${installationId}`
 	);
diff --git a/src/util/jira-utils.test.ts b/src/util/jira-utils.test.ts
index 9a4fed2e5f..dc363a76ed 100644
--- a/src/util/jira-utils.test.ts
+++ b/src/util/jira-utils.test.ts
@@ -115,7 +115,7 @@ describe("Jira Utils", () => {
 			["JIRA-123abcd"],
 			["JIRA-123abcd JIRA-456 abcd", "JIRA-456"]
 		])("matching with whole word", (full, ...issueKeys) => {
-			it(`should match "${full}" to "${issueKeys}"`, () => {
+			it(`should match "${full}" to "${issueKeys.toString()}"`, () => {
 				expect(jiraIssueKeyParser(full)).toEqual(issueKeys ? issueKeys : []);
 			});
 		});
diff --git a/src/util/logger-utils.ts b/src/util/logger-utils.ts
index a157f2dfd0..34114a75f8 100644
--- a/src/util/logger-utils.ts
+++ b/src/util/logger-utils.ts
@@ -40,7 +40,7 @@ class RawLogStream extends Writable {
 			return next();
 		}
 
-		const chunk = safeJsonStringify(record) + "\n";
+		const chunk = `${safeJsonStringify(record)}\n`;
 		this.writeStream.write(chunk, encoding);
 		next();
 	}
diff --git a/src/util/workers-health-monitor.ts b/src/util/workers-health-monitor.ts
index 62484997be..6f0f55be3d 100644
--- a/src/util/workers-health-monitor.ts
+++ b/src/util/workers-health-monitor.ts
@@ -9,7 +9,7 @@ export const startMonitorOnWorker = (parentLogger: Logger, iAmAliveInervalMsec:
 	const logger = parentLogger.child({ isWorker: true });
 	logger.info({ iAmAliveInervalMsec }, "worker config");
 
-	process.on("message", (msg) => {
+	process.on("message", (msg: string) => {
 		logger.info(`worker received a message: ${msg}`);
 		if (msg === CONF_SHUTDOWN_MSG) {
 			logger.warn("shutdown received, stop healthcheck");
@@ -32,7 +32,7 @@ export const startMonitorOnWorker = (parentLogger: Logger, iAmAliveInervalMsec:
 const logRunningProcesses = (logger: Logger) => {
 	exec("ps aux", (err, stdout) => {
 		if (err) {
-			logger.error({ err }, `exec error: ${err}`);
+			logger.error({ err }, `exec error: ${err.toString()}`);
 			return;
 		}
 
@@ -64,7 +64,7 @@ export const startMonitorOnMaster = (parentLogger: Logger, config: {
 					logger.info(`registering a new worker with pid=${workerPid}`);
 					registeredWorkers[workerPid] = true;
 					worker.on("message", () => {
-						logInfoSampled(logger, "workerIsAlive:" + workerPid, `received message from worker ${workerPid}, marking as live`, 100);
+						logInfoSampled(logger, `workerIsAlive:${workerPid}`, `received message from worker ${workerPid}, marking as live`, 100);
 						liveWorkers[workerPid] = Date.now();
 					});
 					worker.on("exit", (code, signal) => {
@@ -87,7 +87,7 @@ export const startMonitorOnMaster = (parentLogger: Logger, config: {
 		if (!workersReadyAt) {
 			if (Object.keys(registeredWorkers).length > config.numberOfWorkersThreshold) {
 				workersReadyAt = new Date(Date.now() + config.workerStartupTimeMsecs);
-				logger.info(`consider workers as ready after ${workersReadyAt}`);
+				logger.info(`consider workers as ready after ${workersReadyAt?.toString()}`);
 			} else {
 				logger.info("no enough workers");
 			}
diff --git a/test/e2e/utils/jira.ts b/test/e2e/utils/jira.ts
index 84ef3d1fff..e5e33764f3 100644
--- a/test/e2e/utils/jira.ts
+++ b/test/e2e/utils/jira.ts
@@ -105,7 +105,7 @@ export const jiraCreateIssue = async (page: Page, projectId: string = testData.p
 	// V3 implementation
 	// await page.click("[data-testid='navigation-apps-sidebar-next-gen.ui.menu.software-backlog-link']");
 	// const taskInput = page.locator("[data-test-id='platform-inline-card-create.ui.form.summary.styled-text-area']");
-	await taskInput.fill("Task " + Date.now());
+	await taskInput.fill("Task " + Date.now().toString());
 	await taskInput.press("Enter");
 	const url = await page.locator("[data-test-id='platform-board-kit.ui.column.draggable-column.styled-wrapper']:first-child [data-test-id='platform-board-kit.ui.card.card'][draggable]").last().getAttribute("id");
 	return url?.replace("card-", "") || "";
diff --git a/test/setup/matchers/to-be-called-with-delay.ts b/test/setup/matchers/to-be-called-with-delay.ts
index 1b703821e5..b9060ba0cb 100644
--- a/test/setup/matchers/to-be-called-with-delay.ts
+++ b/test/setup/matchers/to-be-called-with-delay.ts
@@ -8,7 +8,7 @@ declare namespace jest {
 
 expect.extend({
 	toBeCalledWithDelaySec: async (received: jest.Mock<unknown>, expectedDelaySec: number) => {
-		const actual = received.mock?.calls[0][0].DelaySeconds;
+		const actual = received.mock?.calls[0][0].DelaySeconds as number;
 		const pass = actual == expectedDelaySec;
 		const message = () => `Expected parameter to have DelaySeconds = ${expectedDelaySec} ${pass ? "" : `but was ${actual}`}`;
 
diff --git a/test/setup/matchers/to-promise.ts b/test/setup/matchers/to-promise.ts
index 42694158ec..82548bf431 100644
--- a/test/setup/matchers/to-promise.ts
+++ b/test/setup/matchers/to-promise.ts
@@ -25,7 +25,7 @@ expect.extend({
 		}
 		return {
 			pass: false,
-			message: () => `Expected promise to resolve, however it rejected with error: \n${error.stack}\n`
+			message: () => `Expected promise to resolve, however it rejected with error: \n${error.stack ?? "Missing Stack"}\n`
 		};
 	},
 	toReject: async (promise: Promise<unknown>) => {
diff --git a/test/setup/setup.ts b/test/setup/setup.ts
index 7374757a13..7ffbdbf6ab 100644
--- a/test/setup/setup.ts
+++ b/test/setup/setup.ts
@@ -131,7 +131,7 @@ beforeAll(async () => {
 });
 
 beforeEach(() => {
-	const instance = envVars.APP_KEY.split(".").pop();
+	const instance = envVars.APP_KEY.split(".").pop()!;
 	global.jiraHost = process.env.ATLASSIAN_URL || `https://${instance}.atlassian.net`;
 	global.jiraStaginHost = process.env.ATLASSIAN_URL?.replace(".atlassian.net", ".jira-dev.com") || `https://${instance}.jira-dev.com`;
 	global.jiraNock = nock(global.jiraHost);
diff --git a/test/snapshots/routes/api/api-router.test.ts.snap b/test/snapshots/routes/api/api-router.test.ts.snap
index 4dcd234053..4729a3adbb 100644
--- a/test/snapshots/routes/api/api-router.test.ts.snap
+++ b/test/snapshots/routes/api/api-router.test.ts.snap
@@ -33,7 +33,7 @@ Object {
   "failedConnections": Array [
     Object {
       "deleted": false,
-      "error": "Error executing Axios Request: Request failed with status code 500. More details in logs",
+      "error": "Error: Error executing Axios Request: Request failed with status code 500. More details in logs",
       "id": 1234,
     },
   ],
diff --git a/test/snapshots/snapshot-resolver.ts b/test/snapshots/snapshot-resolver.ts
index 88e311a535..840ff12224 100644
--- a/test/snapshots/snapshot-resolver.ts
+++ b/test/snapshots/snapshot-resolver.ts
@@ -9,7 +9,7 @@ module.exports = {
 	 * @param testPath Path of the test file being tested
 	 * @param snapshotExtension The extension for snapshots (.snap usually)
 	 */
-	resolveSnapshotPath:(testPath, snapshotExtension) =>
+	resolveSnapshotPath:(testPath: string, snapshotExtension: string) =>
 		path.join(snapshotDirPath, testPath.replace(srcPath, "") + snapshotExtension),
 
 	/**
diff --git a/test/utils/database-state-creator.ts b/test/utils/database-state-creator.ts
index 5076a463bd..3bc146e1ed 100644
--- a/test/utils/database-state-creator.ts
+++ b/test/utils/database-state-creator.ts
@@ -120,7 +120,7 @@ export class DatabaseStateCreator {
 			uuid: v4(),
 			appId: 12321,
 			gitHubBaseUrl: gheUrl,
-			gitHubClientId: "client-id" + Math.random(),
+			gitHubClientId: "client-id" + Math.random().toString(),
 			gitHubClientSecret: "client-secret",
 			webhookSecret: "webhook-secret",
 			privateKey: fs.readFileSync(path.resolve(__dirname, "../../test/setup/test-key.pem"), { encoding: "utf8" }),
diff --git a/yarn.lock b/yarn.lock
index 797931b3ae..d56fa9ecc8 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1235,6 +1235,11 @@
   dependencies:
     "@types/node" "*"
 
+"@types/safe-json-stringify@^1.1.2":
+  version "1.1.2"
+  resolved "https://packages.atlassian.com/api/npm/npm-remote/@types/safe-json-stringify/-/safe-json-stringify-1.1.2.tgz#913796617042de2259f62ce82843c239258ca287"
+  integrity sha512-Hj/LZMBXFH3Qj9sNmNu6syBpkZqBaM00HgP7naf9CnZhB3kdxmrenWUD2cY6vvTWjuBM3NPOLknPKDUOQuTWXA==
+
 "@types/semver@^7.3.12":
   version "7.5.1"
   resolved "https://packages.atlassian.com/api/npm/npm-remote/@types/semver/-/semver-7.5.1.tgz#0480eeb7221eb9bc398ad7432c9d7e14b1a5a367"