diff --git a/lib/elm-make-runner.js b/lib/elm-make-runner.js
index dde7e05..c378b94 100644
--- a/lib/elm-make-runner.js
+++ b/lib/elm-make-runner.js
@@ -88,7 +88,13 @@ export default class ElmMakeRunner {
         }
       }
     } else {
-      filePathsToCompile = [editorFilePath];
+      if (isTestFilePath && process.platform === 'win32') {
+        // Workaround for https://github.com/halohalospecial/atom-elmjutsu/issues/131#issuecomment-429445645
+        const relativeEditorFilePath = path.relative(projectDirectory, editorFilePath);
+        filePathsToCompile = [relativeEditorFilePath];
+      } else {
+        filePathsToCompile = [editorFilePath];
+      }
     }
 
     const outputPath = '/dev/null'; // TODO: Make this configurable (elmjutsu-config.json).