diff --git a/Sources/geometrize/GeometrizeModelHillClimb.swift b/Sources/geometrize/GeometrizeModelHillClimb.swift
index ba8d31f..d90364e 100644
--- a/Sources/geometrize/GeometrizeModelHillClimb.swift
+++ b/Sources/geometrize/GeometrizeModelHillClimb.swift
@@ -64,18 +64,24 @@ class GeometrizeModelHillClimb: GeometrizeModelBase {
             for _ in 0..<maxThreads {
                 let seed = UInt64(baseRandomSeed + randomSeedOffset) // TODO: fix
                 randomSeedOffset += 1
-                taskGroup.addTask {
-                    let state = await bestHillClimbStateAsync(
-                        shapeCreator: shapeCreator,
-                        alpha: alpha,
-                        n: shapeCount,
-                        age: maxShapeMutations,
-                        target: target,
-                        current: current,
-                        lastScore: lastScore,
-                        energyFunction: energyFunction,
-                        seed: seed
-                    )
+                taskGroup.addTask { [current] in
+                    var generator = SplitMix64(seed: seed)
+                    let state = await withCheckedContinuation { continuation in
+                        var buffer = current
+                        let state = bestHillClimbState(
+                            shapeCreator: shapeCreator,
+                            alpha: alpha,
+                            n: shapeCount,
+                            age: maxShapeMutations,
+                            target: target,
+                            current: current,
+                            buffer: &buffer,
+                            lastScore: lastScore,
+                            energyFunction: energyFunction,
+                            using: &generator
+                        )
+                        continuation.resume(returning: state)
+                    }
                     return state
                 }
             }
diff --git a/Sources/geometrize/HillClimbAsync.swift b/Sources/geometrize/HillClimbAsync.swift
deleted file mode 100644
index 20c9895..0000000
--- a/Sources/geometrize/HillClimbAsync.swift
+++ /dev/null
@@ -1,162 +0,0 @@
-import Foundation
-
-/// Gets the best state using a hill climbing algorithm.
-/// - Parameters:
-///   - shapeCreator: A function that will create the shapes that will be chosen from.
-///   - alpha: The opacity of the shape.
-///   - n: The number of random states to generate.
-///   - age: The number of hillclimbing steps.
-///   - target: The target bitmap.
-///   - current: The current bitmap.
-///   - buffer: The buffer bitmap.
-///   - lastScore: The last score.
-///   - energyFunction: A function to calculate the energy.
-///   - seed: The Random number generator to use.
-/// - Returns: The best state acquired from hill climbing i.e. the one with the lowest energy.
-func bestHillClimbStateAsync( // swiftlint:disable:this function_parameter_count
-    shapeCreator: ShapeCreator,
-    alpha: UInt8,
-    n: Int,
-    age: Int,
-    target: Bitmap,
-    current: Bitmap,
-    lastScore: Double,
-    energyFunction: EnergyFunction = defaultEnergyFunction,
-    seed: UInt64
-) async -> State {
-    var buffer = current
-    var generator = SplitMix64(seed: seed)
-    return await withCheckedContinuation { continuation in
-        let state: State = bestRandomState(
-            shapeCreator: shapeCreator,
-            alpha: alpha,
-            n: n,
-            target: target,
-            current: current,
-            buffer: &buffer, // TODO: should it be inout?
-            lastScore: lastScore,
-            energyFunction: energyFunction,
-            using: &generator
-        )
-        let resState = hillClimb(
-            state: state,
-            maxAge: age,
-            target: target,
-            current: current,
-            buffer: &buffer, // TODO: should it be inout?
-            lastScore: lastScore,
-            energyFunction: energyFunction,
-            using: &generator
-        )
-        continuation.resume(returning: resState)
-    }
-}
-
-/// Hill climbing optimization algorithm, attempts to minimize energy (the error/difference).
-/// https://en.wikipedia.org/wiki/Hill_climbing
-/// - Parameters:
-///   - state: The state to optimize.
-///   - maxAge: The maximum age.
-///   - target: The target bitmap.
-///   - current: The current bitmap.
-///   - buffer: The buffer bitmap.
-///   - lastScore: The last score.
-///   - energyFunction: An energy function to be used.
-///   - using: The Random number generator to use.
-/// - Returns: The best state found from hillclimbing.
-func hillClimbAsync( // swiftlint:disable:this function_parameter_count
-    state: State,
-    maxAge: Int,
-    target: Bitmap,
-    current: Bitmap,
-    buffer: inout Bitmap,
-    lastScore: Double,
-    energyFunction: EnergyFunction,
-    using generator: inout SplitMix64
-) -> State {
-    let xRange = 0...target.width - 1, yRange = 0...target.height - 1
-    var s: State = state
-    var bestState: State = state
-    var bestEnergy: Double = bestState.score
-    var age: Int = 0
-    while age < maxAge {
-        let undo = s
-        let alpha = s.alpha
-        s = s.mutate(x: xRange, y: yRange, using: &generator) { aShape in
-            return energyFunction(
-                aShape.rasterize(x: xRange, y: yRange),
-                alpha,
-                target,
-                current,
-                &buffer,
-                lastScore
-            )
-        }
-        if s.score >= bestEnergy {
-            s = undo
-        } else {
-            bestEnergy = s.score
-            bestState = s
-            age = Int.max // TODO: What's the point??? And following increment overflows.
-        }
-        if age == Int.max {
-            age = 0
-        } else {
-            age += 1
-        }
-    }
-    return bestState
-}
-
-/// Gets the best state using a random algorithm.
-/// - Parameters:
-///   - shapeCreator: A function that will create the shapes that will be chosen from.
-///   - alpha: The opacity of the shape.
-///   - n: The number of states to try.
-///   - target: The target bitmap.
-///   - current: The current bitmap.
-///   - buffer: The buffer bitmap.
-///   - lastScore: The last score.
-///   - energyFunction: An energy function to be used.
-///   - using: The Random number generator to use.
-/// - Returns: The best random state i.e. the one with the lowest energy.
-private func bestRandomStateAsync( // swiftlint:disable:this function_parameter_count
-    shapeCreator: ShapeCreator,
-    alpha: UInt8,
-    n: Int,
-    target: Bitmap,
-    current: Bitmap,
-    buffer: inout Bitmap,
-    lastScore: Double,
-    energyFunction: EnergyFunction,
-    using generator: inout SplitMix64
-) -> State {
-    let xRange = 0...target.width - 1, yRange = 0...target.height - 1
-    let shape = shapeCreator(&generator).setup(x: xRange, y: yRange, using: &generator)
-    var bestEnergy: Double = energyFunction(
-        shape.rasterize(x: xRange, y: yRange),
-        alpha,
-        target,
-        current,
-        &buffer,
-        lastScore
-    )
-    var bestState: State = State(score: bestEnergy, alpha: alpha, shape: shape)
-    for i in 0...n {
-        let shape = shapeCreator(&generator).setup(x: xRange, y: yRange, using: &generator)
-        let energy: Double = energyFunction(
-            shape.rasterize(x: xRange, y: yRange),
-            alpha,
-            target,
-            current,
-            &buffer,
-            lastScore
-        )
-        let state: State = State(score: energy, alpha: alpha, shape: shape)
-        if i == 0 || energy < bestEnergy {
-            bestEnergy = energy
-            bestState = state
-        }
-    }
-    return bestState
-}
diff --git a/Sources/geometrize/SVGAsyncIterator.swift b/Sources/geometrize/SVGAsyncIterator.swift
index 1b89545..362288b 100644
--- a/Sources/geometrize/SVGAsyncIterator.swift
+++ b/Sources/geometrize/SVGAsyncIterator.swift
@@ -116,6 +116,23 @@ public struct SVGAsyncIterator: AsyncIteratorProtocol {
             if verbose {
                 print("Step \(stepCounter)", terminator: "")
             }
+            let stepResult = await withCheckedContinuation { continuation in
+                var buffer = current
+                let state = bestHillClimbState(
+                    shapeCreator: shapeCreator,
+                    alpha: alpha,
+                    n: shapeCount,
+                    age: maxShapeMutations,
+                    target: target,
+                    current: current,
+                    buffer: &buffer,
+                    lastScore: lastScore,
+                    energyFunction: energyFunction,
+                    using: &generator
+                )
+                continuation.resume(returning: state)
+            }
+
             let stepResult = await runner.stepAsync(
                 options: runnerOptions,
                 energyFunction: defaultEnergyFunction,