Python Feature Flags

Feature flag / toggle management built for Python apps

Feature flags are a software development best practice of gating functionality. Functionality can be deployed “off”, then turned on via the feature flag, separate from deployment. With feature flags, you can manage the entire lifecycle of a feature.

LaunchDarkly's Python SDK lets you create and maintain Python feature flags across your entire application. You can centrally manage all of your feature flags, perform granular rollouts, and kill bad features without redeploying. All flag values are evaluated in-memory, so there is no latency for your users. New flag settings are streamed to the SDKs in real-time, so any changes to your flag rules will take effect almost immediately.

LaunchDarkly Dashboard & Feature Flag Manager
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Here are some product benefits of LaunchDarkly's Python Feature Flag SDK:

  • Real-time feature flags via a streaming API
  • In-memory flag evaluation with near zero latency
  • No external HTTP calls for flag values
  • Boolean & multivariate feature flags
  • Custom percentage rollouts and targeting rules
  • A/B testing
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Flag management benefits:

  • Audit log
  • Custom roles
  • Custom webhooks
  • Integrations for Slack and HipChat

Python Feature Flags

Let's create a Python feature flag for a "One Click Checkout"

1.Install the SDK with pip

Check out our open source Python SDK on GitHub or read through the reference documentation.

       pip install ldclient-py

2.Create a new LaunchDarkly client

       ld_client = LDClient("YOUR_SDK_KEY")

3.Create a feature flag in LaunchDarkly

A flag allows you to manage a feature from the LaunchDarkly dashboard.

4.Wrap your code with a feature flag

First, create a user.  You can pass us any data about users for targeting and segmentation. 
Then, call variation and see whether the flag is on for that user.

        user = {
          "key": "",
          "firstName": "Bob",
          "lastName": "Loblaw",
          "custom": {
            "groups": "beta_testers"

        show_feature = ld_client.variation("one_click_checkout", user, False)

        if show_feature:
          # Showing One Click Checkout
          # Not Showing One Click Checkout


5.Manage your flag

Use LaunchDarkly to determine which users see the feature.
You can roll out to a percentage of your users or target individual users/groups.

Create your own Python feature flags in minutes.
How It Works