Overview

Datadog Feature Flags for server-side applications allow you to remotely control feature availability, run experiments, and roll out new functionality with confidence. Server-side SDKs integrate with the Datadog SDK and use Remote Configuration to receive flag updates in real time.

This guide covers the common setup required for all server-side SDKs, including Agent configuration and application environment variables. Select your language or framework to view SDK-specific setup instructions:

Prerequisites

Before setting up server-side feature flags, ensure you have:

• Datadog Agent 7.55 or later installed and running
• Datadog API key configured
• APM tracing enabled in your application
• Remote Configuration enabled for your organization. Verify this in Organization Settings.

Agent configuration

Server-side feature flags use Remote Configuration to deliver flag configurations to your application. Enable Remote Configuration in your Datadog Agent by setting DD_REMOTE_CONFIGURATION_ENABLED=true or adding remote_configuration.enabled: true to your datadog.yaml.

See the Remote Configuration documentation for detailed setup instructions across different deployment environments.

Polling interval

The Agent polls Datadog for configuration updates at a configurable interval. This interval determines the average time between making a flag change in the UI and the change becoming available to your application.

# Optional: Configure polling interval (default: 60s)
DD_REMOTE_CONFIGURATION_REFRESH_INTERVAL=10s

Application configuration

Configure your application with the standard Datadog environment variables. These are common across all server-side SDKs:

# Required: Service identification
DD_SERVICE=<YOUR_SERVICE_NAME>
DD_ENV=<YOUR_ENVIRONMENT>
DD_VERSION=<YOUR_APP_VERSION>

# Agent connection (if not using default localhost:8126)
DD_AGENT_HOST=localhost
DD_TRACE_AGENT_PORT=8126

# Enable Remote Configuration in the SDK
DD_REMOTE_CONFIG_ENABLED=true

# Enable the feature flagging provider (required for most SDKs)
DD_EXPERIMENTAL_FLAGGING_PROVIDER_ENABLED=true

# Enable flag evaluation metrics (required for flag evaluation tracking)
DD_METRICS_OTEL_ENABLED=true

Testing with in-memory providers

Datadog supports these testing approaches:

• Integration tests: Point DatadogProvider at a dedicated test environment and control flag values from the Datadog UI. This exercises the real provider end-to-end, including Remote Configuration delivery.
• Unit tests: Swap DatadogProvider for OpenFeature’s standard InMemoryProvider (or an equivalent test stub, where no in-memory provider is available in the language) and set flag values directly in test code. This keeps tests hermetic and offline.

This section covers the in-memory approach. Because the OpenFeature API is designed to make providers swappable at runtime, your application code does not change — only the provider registered during test setup.

A typical test follows this pattern:

1. Build a map of flag keys to variants in your test setup.
2. Register an InMemoryProvider with that map through the OpenFeature API.
3. Call the OpenFeature client in the units being tested. The InMemoryProvider returns the flag assignments configured at test setup.
4. Reset the provider in test teardown to avoid cross-test state leakage.

See your language’s SDK page (select from the top of this page) for a concrete test example.

Context attribute requirements

Use flat attributes in your evaluation context:

const evaluationContext = {
  targetingKey: req.session?.userID,
  companyId: req.session?.companyID,
  tier: 'enterprise'
};

const value = client.getBooleanValue('my-flag', false, evaluationContext);

Avoid nested objects and arrays:

// These attributes will cause exposure events to be dropped
const evaluationContext = {
  targetingKey: req.session?.userID,
  company: { id: req.session?.companyID },  // nested object - NOT SUPPORTED
  roles: ['admin', 'user']                   // array - NOT SUPPORTED
};

Further reading

Más enlaces, artículos y documentación útiles:

Client-Side Feature FlagsDOCUMENTATION Remote ConfigurationDOCUMENTATION