Zenmanage Python SDK

Add feature flags to your Python application in minutes. Control feature rollouts, A/B test, and manage configurations without deploying code.

Why Zenmanage?

• Fast: rules cached locally for low-latency evaluation
• Targeted: roll out by user, organization, or custom attributes
• Safe: graceful defaults and typed accessors
• Insightful: optional usage reporting
• Testable: deterministic rollout logic and isolated rule engine

Installation

pip install zenmanage

Requirements: Python 3.9+

Key Compatibility

• Supported in Python SDK: case-sensitive server keys prefixed with srv_
• Not supported in Python SDK: client keys (cli_) and mobile keys (mob_) (initialization fails fast)

Get Started in 60 Seconds

1. Get your server key (srv_...) from zenmanage.com
2. Initialize the SDK:

from zenmanage import ConfigBuilder, Zenmanage

zenmanage = Zenmanage(
    ConfigBuilder.create()
    .with_environment_token("srv_your_server_key_here")
    .build()
)

3. Check a feature flag:

flag = zenmanage.flags().single("new-dashboard", False)

if flag.is_enabled():
    show_new_dashboard()
else:
    show_old_dashboard()

Common Use Cases

Async Frameworks (FastAPI, Starlette, etc.)

from zenmanage import AsyncZenmanage, ConfigBuilder, Context

zenmanage = AsyncZenmanage(
    ConfigBuilder.from_environment().build()
)

async def is_enabled_for_user(user_id: str) -> bool:
    context = Context.single("user", user_id)
    flag = await zenmanage.flags().with_context(context).single("new-dashboard", False)
    return flag.is_enabled()

Remember to close the async client on shutdown:

await zenmanage.aclose()

Roll Out a New Feature Gradually

from zenmanage import Context

context = Context.single("user", user_id, user_name)

beta_access = (
    zenmanage.flags()
    .with_context(context)
    .single("beta-program", False)
    .is_enabled()
)

if beta_access:
    enable_beta_features()

A/B Testing

from zenmanage import Attribute, Context

context = Context.single("user", user.id, user.name)
context.add_attribute(Attribute.from_strings("country", [user.country]))
context.add_attribute(Attribute.from_strings("plan", [user.subscription_plan]))

variant = (
    zenmanage.flags()
    .with_context(context)
    .single("checkout-flow", "multi-page")
    .as_string()
)

if variant == "one-page":
    render_one_page_checkout()
else:
    render_multi_page_checkout()

Percentage Rollouts

from zenmanage import Context

context = Context.single("user", user_id)

flag = (
    zenmanage.flags()
    .with_context(context)
    .single("new-checkout-flow", False)
)

if flag.is_enabled():
    render_new_checkout()
else:
    render_classic_checkout()

How it works:

• Configure rollout percentage (0-100) and salt in Zenmanage
• SDK computes CRC32B bucket from salt:contextIdentifier
• Same user always lands in same bucket
• Increasing percentage only adds users, never removes included users

Use Defaults Across Many Flags

from zenmanage import DefaultsCollection

defaults = DefaultsCollection.from_dict(
    {
        "new-ui": True,
        "api-version": "v2",
        "max-items": 100,
    }
)

flag_manager = zenmanage.flags().with_defaults(defaults)
new_ui = flag_manager.single("new-ui").as_bool()

Fetch All Flags

for flag in zenmanage.flags().all():
    print(flag.key, flag.get_value())

Configuration

import logging

config = (
    ConfigBuilder.create()
    .with_environment_token("srv_your_server_key_here")
    .with_cache_ttl(3600)
    .with_cache_backend("memory")  # memory | filesystem | null
    .with_cache_directory(".cache/zenmanage")  # required for filesystem
    .with_usage_reporting(True)
    .with_api_endpoint("https://api.zenmanage.com")
    .with_logger(logging.getLogger("my-app"))
    .build()
)

You can also load from environment variables:

• ZENMANAGE_ENVIRONMENT_TOKEN
• ZENMANAGE_CACHE_TTL
• ZENMANAGE_CACHE_BACKEND
• ZENMANAGE_CACHE_DIR
• ZENMANAGE_ENABLE_USAGE_REPORTING
• ZENMANAGE_API_ENDPOINT

config = ConfigBuilder.from_environment().build()

Cache Backends

• memory: default, fastest, process-local
• filesystem: durable between process restarts
• null: disables caching

Custom cache objects are supported with with_cache(...) as long as they implement get, set, has, delete, and clear.

Examples

See examples/README.md for runnable examples:

• simple-flags
• ab-testing
• caching
• context-based-flags
• defaults
• percentage-rollouts
• django-integration
• flask-integration
• fastapi-async

Framework integrations: docs/FRAMEWORK_INTEGRATIONS.md

License

MIT