server SDK
Python feature flags
There is no dedicated Python page on docs.featureflow.io. The install command and the calls below are from the featureflow-python-sdk README. The package name on PyPI is featureflow-sdk. The compatibility table lists JSON config values and goal tracking as not yet supported for Python.
No separate docs page yet. GitHubfeatureflow-sdk
Set it up with your coding agent
Paste this into Claude Code, Cursor or any coding agent. It installs the Python SDK, creates the client and evaluates your first flag.
Set up Featureflow with the Python SDK in this project. Run `npx skills add featureflow/featureflow-skills --skill featureflow-setup -y` first, then follow the skill. Keep SDK keys in env vars.
Or set it up by hand
Install
python -m pip install featureflow-sdkInitialise
import os
from featureflow import Featureflow
featureflow = Featureflow(os.environ["FEATUREFLOW_SERVER_KEY"])Evaluate a flag
from featureflow import User
user = User(key=user_id, attributes={"tier": "gold"})
if featureflow.evaluate("my-cool-feature", user).isOn():
print("I'm enabled")Kill switch
Leave the flag off and branch on evaluate(key, user).isOn(). Create one client for the life of the process. The README says the constructor starts background threads, so a client per request re-downloads flags.
The operational side is the kill switch. Turning the flag off does not require a redeploy.
Gradual rollout
The percentage is a rule on the flag. Pass a stable user key. The README's multivariate check is evaluated.is_("variant-b"), with a trailing underscore, and evaluated.value() returns the variant string.
See progressive rollout for the dashboard control. Release pipelines and approval workflows, if the change itself needs a review, are on the Business plan at $399 a month. That price is on the pricing page.
Targeting
User(key=..., attributes={"tier": "gold"}) is the documented user. Optional application="checkout-api" tags the workload. FEATUREFLOW_APPLICATION is used when you do not pass application. Do not call a track or JSON method. The README does not show one, and the compatibility table says both are not yet supported.
Frequently asked questions
What is the PyPI package?
featureflow-sdk. Install with python -m pip install featureflow-sdk. Import Featureflow and User from featureflow. The repository is github.com/featureflow/featureflow-python-sdk.
Does Python support goal tracking?
Not yet. docs.featureflow.io/sdk-compatibility lists Python as not yet supported for goal tracking and for JSON configuration values.
How do I check a named variant?
The README uses evaluated.is_("variant-b") and evaluated.value(). isOn() checks the on variant.