# Diff Feature Flags Before Running Tests

DevFeed: [Diff Feature Flags Before Running Tests](<https://devfeed.tech/articles/diff-feature-flags-before-running-tests-28887.md>)

Original publisher: [Read original article](<https://glebbahmutov.com/blog/diff-feature-flags-before-testing/>)

Author: Gleb Bahmutov

Published: 2025-09-23T04:00:00Z

Content type: tutorial

Language: en

Sources: [Gleb Bahmutov](<https://devfeed.tech/sources/gleb-bahmutov.md>)

Topics: [feature flags](<https://devfeed.tech/topics/feature-flags.md>), [Testing](<https://devfeed.tech/topics/testing.md>), [Cypress](<https://devfeed.tech/topics/cypress.md>), [GitHub Actions](<https://devfeed.tech/topics/github-actions.md>), [JSON](<https://devfeed.tech/topics/json.md>), [Command-line interface](<https://devfeed.tech/topics/cli.md>)

Tags: [advice](<https://devfeed.tech/tags/advice.md>), [cli](<https://devfeed.tech/tags/cli.md>), [cypress](<https://devfeed.tech/tags/cypress.md>), [e2e](<https://devfeed.tech/tags/e2e.md>), [feature-flags](<https://devfeed.tech/tags/feature-flags.md>), [github-actions](<https://devfeed.tech/tags/github-actions.md>), [json](<https://devfeed.tech/tags/json.md>), [process](<https://devfeed.tech/tags/process.md>), [testing](<https://devfeed.tech/tags/testing.md>), [tests](<https://devfeed.tech/tags/tests.md>)

## AI overview

This tutorial explains how to detect unexpected feature-flag changes before end-to-end tests run. It shows how to save LaunchDarkly flags as JSON, compare current flags with the saved version in GitHub Actions, and update the saved configuration when defaults change.

## Source excerpt

As I explained in my previous blog post on feature flags and testing, you need