diff --git a/__tests__/env.js b/__tests__/env.js
deleted file mode 100644
index b6e5dee0..00000000
--- a/__tests__/env.js
+++ /dev/null
@@ -1 +0,0 @@
-process.env.UNIT_TEST = "true"
\ No newline at end of file
diff --git a/__tests__/env.ts b/__tests__/env.ts
new file mode 100644
index 00000000..2c33a5a1
--- /dev/null
+++ b/__tests__/env.ts
@@ -0,0 +1 @@
+process.env.UNIT_TEST = 'true'
diff --git a/jest.config.js b/jest.config.js
index 9eaa7c54..159387d1 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -8,7 +8,7 @@ module.exports = {
     '^.+\\.ts$': 'ts-jest'
   },
   verbose: true,
-  setupFiles: ["<rootDir>/__tests__/env.js"],
+  setupFiles: ['<rootDir>/__tests__/env.ts'],
   collectCoverage: true,
-  collectCoverageFrom: ['src/*.ts','!src/constants.ts']
-}
\ No newline at end of file
+  collectCoverageFrom: ['src/*.ts', '!src/constants.ts']
+}