diff --git a/Sources/SwiftMutationTesting/Execution/TestExecutionStage.swift b/Sources/SwiftMutationTesting/Execution/TestExecutionStage.swift
index e6ecbcd..b344567 100644
--- a/Sources/SwiftMutationTesting/Execution/TestExecutionStage.swift
+++ b/Sources/SwiftMutationTesting/Execution/TestExecutionStage.swift
@@ -72,21 +72,7 @@ struct TestExecutionStage: Sendable {
         )
         try? FileManager.default.removeItem(atPath: launched.xcresultPath)
 
-        let status = outcome.asExecutionStatus
-        let killerTestFile = resolveKillerTestFile(status: status)
-        let result = ExecutionResult(
-            descriptor: mutant, status: status, testDuration: launched.duration,
-            killerTestFile: killerTestFile
-        )
-        await deps.cacheStore.store(status: status, for: key, killerTestFile: killerTestFile)
-        let index = await deps.counter.increment()
-        await deps.reporter.report(
-            .mutantFinished(
-                descriptor: mutant, status: status,
-                index: index, total: deps.counter.total
-            )
-        )
-        return result
+        return await recordResult(mutant: mutant, key: key, outcome: outcome, duration: launched.duration)
     }
 
     private func runSPM(
@@ -105,10 +91,19 @@ struct TestExecutionStage: Sendable {
 
         let outcome = SPMResultParser().parse(exitCode: launched.exitCode, output: launched.output)
         await context.pool.release(slot)
+        return await recordResult(mutant: mutant, key: key, outcome: outcome, duration: launched.duration)
+    }
+
+    private func recordResult(
+        mutant: MutantDescriptor,
+        key: MutantCacheKey,
+        outcome: TestRunOutcome,
+        duration: Double
+    ) async -> ExecutionResult {
         let status = outcome.asExecutionStatus
         let killerTestFile = resolveKillerTestFile(status: status)
         let result = ExecutionResult(
-            descriptor: mutant, status: status, testDuration: launched.duration,
+            descriptor: mutant, status: status, testDuration: duration,
             killerTestFile: killerTestFile
         )
         await deps.cacheStore.store(status: status, for: key, killerTestFile: killerTestFile)
diff --git a/Tests/SwiftMutationTestingTests/Unit/Infrastructure/TestFilesHasherTests.swift b/Tests/SwiftMutationTestingTests/Unit/Infrastructure/TestFilesHasherTests.swift
index c6c4a51..71eb06b 100644
--- a/Tests/SwiftMutationTestingTests/Unit/Infrastructure/TestFilesHasherTests.swift
+++ b/Tests/SwiftMutationTestingTests/Unit/Infrastructure/TestFilesHasherTests.swift
@@ -62,6 +62,29 @@ struct TestFilesHasherTests {
         #expect(result.keys.contains("Tests/FooTests.swift"))
     }
 
+    @Test("Given test file symlinked outside project, when hashPerFile called, then absolute path is used as key")
+    func hashPerFileUsesAbsolutePathForExternalSymlink() throws {
+        let projectDir = try FileHelpers.makeTemporaryDirectory()
+        defer { FileHelpers.cleanup(projectDir) }
+
+        let externalDir = try FileHelpers.makeTemporaryDirectory()
+        defer { FileHelpers.cleanup(externalDir) }
+
+        try FileHelpers.write("let t = 1", named: "ExternalTests.swift", in: externalDir)
+
+        let testsDir = projectDir.appendingPathComponent("Tests")
+        try FileManager.default.createDirectory(at: testsDir, withIntermediateDirectories: true)
+        let symlinkURL = testsDir.appendingPathComponent("ExternalTests.swift")
+        let targetURL = externalDir.appendingPathComponent("ExternalTests.swift")
+        try FileManager.default.createSymbolicLink(at: symlinkURL, withDestinationURL: targetURL)
+
+        let result = TestFilesHasher().hashPerFile(projectPath: projectDir.path)
+
+        #expect(result.count == 1)
+        let key = result.keys.first!
+        #expect(!key.hasPrefix("Tests/"))
+    }
+
     @Test("Given non-existent path, when hashPerFile called, then empty map is returned")
     func hashPerFileReturnsEmptyForNonExistentPath() {
         let result = TestFilesHasher().hashPerFile(projectPath: "/nonexistent/path/xyz")