diff --git a/clean_files.txt b/clean_files.txt
index 8fda272a91..3ebec75466 100644
--- a/clean_files.txt
+++ b/clean_files.txt
@@ -160,6 +160,7 @@ themes/brainy
 themes/brunton
 themes/candy
 themes/easy
+themes/elixr
 themes/essential
 themes/githelpers.theme.bash
 themes/inretio
diff --git a/themes/elixr/elixr.theme.bash b/themes/elixr/elixr.theme.bash
index 266abbad43..d266fae89d 100644
--- a/themes/elixr/elixr.theme.bash
+++ b/themes/elixr/elixr.theme.bash
@@ -1,15 +1,16 @@
-#!/usr/bin/env bash
+# shellcheck shell=bash
+# shellcheck disable=SC2034 # Expected behavior for themes.
 
-SCM_THEME_PROMPT_DIRTY=" ${red}✗"
-SCM_THEME_PROMPT_CLEAN=" ${bold_green}✓"
-SCM_THEME_PROMPT_PREFIX=" ${green}| "
-SCM_THEME_PROMPT_SUFFIX="${green} |"
+SCM_THEME_PROMPT_DIRTY=" ${red?}✗"
+SCM_THEME_PROMPT_CLEAN=" ${bold_green?}✓"
+SCM_THEME_PROMPT_PREFIX=" ${green?}| "
+SCM_THEME_PROMPT_SUFFIX="${green?} |"
 SCM_NONE_CHAR='◐ '
 SCM_GIT_SHOW_MINIMAL_INFO=true
-GIT_THEME_PROMPT_DIRTY=" ${red}✗"
-GIT_THEME_PROMPT_CLEAN=" ${bold_green}✓"
-GIT_THEME_PROMPT_PREFIX=" ${green}|"
-GIT_THEME_PROMPT_SUFFIX="${green}|"
+GIT_THEME_PROMPT_DIRTY=" ${red?}✗"
+GIT_THEME_PROMPT_CLEAN=" ${bold_green?}✓"
+GIT_THEME_PROMPT_PREFIX=" ${green?}|"
+GIT_THEME_PROMPT_SUFFIX="${green?}|"
 
 RVM_THEME_PROMPT_PREFIX="|"
 RVM_THEME_PROMPT_SUFFIX=" d|"
@@ -17,7 +18,7 @@ RVM_THEME_PROMPT_SUFFIX=" d|"
 BOLD="\[\e[1m\]"
 
 function prompt_command() {
-  PS1="\n${bold_cyan}$(scm_prompt_char_info)$(virtualenv_prompt) ${bold_cyan}\w :${reset_color}${normal}${BOLD} "
+	PS1="\n${bold_cyan?}$(scm_prompt_char_info)$(virtualenv_prompt) ${bold_cyan}\w :${reset_color?}${normal?}${BOLD} "
 }
 
 safe_append_prompt_command prompt_command