Feature flags for JavaScript
Mitigate risk and accelerate delivery with Optimizely Rollouts
- Get unlimited feature flags and environments
- Remotely enable features outside of app store releases
- Roll back poor-performing features with a kill switch
- Run betas or provision features to specific audiences
Free Feature Flags
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Build and release with confidence
Feature flags, also known as switches or toggles, allow you to turn functionality on and off without deploying new code. This increases control, allowing you to release more frequently and test-and-learn without impacting the user experience.
Roll out and roll back
Rollouts help you mitigate risk. Start by releasing your feature behind a disabled feature flag with 0% traffic allocated. When you are ready to release to customers, you can gradually increase the rollout as needed as you iterate on and refine your feature.
Embrace continuous delivery
Separate code deployment from feature enablement. Get new features into production safely and faster with feature flags and make the shift to continuous delivery.
Target audiences
Optimizely Rollouts includes audiences that give you control over which users to include in a rollout. Target audiences using custom attributes like their app version, location, device type, or subscription plan.
Works in the languages you do
Create feature flags, target audiences, and roll out and roll back with zero-latency SDKs for JavaScript and more.
Fast decision engine
Roll out features in performance-critical codepaths. Our SDKs bucket users in memory so rollouts have no impact on latency.
Open platform
Open-source SDKs with pluggable components give you control over network activity.
Read the Docs
Get integrated with quickstarts for every language.
import optimizely
optimizely_client = optimizely.Optimizely(datafile)
# Evaluate a feature flag
enabled = optimizely_client.is_feature_enabled('my_feature'
, 'user_123'
)
if enabled
:
# Show your feature
else:
# Hide your feature
import com.optimizely.ab.Optimizely;
Optimizely optimizely = Optimizely.builder(datafile).build();
// Evaluate a feature flag
Boolean enabled = optimizely.isFeatureEnabled("my_feature"
, "user_123"
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
import "optimizely"
optimizely_client = Optimizely::Project.new(datafile)
# Evaluate a feature flag
enabled = optimizely_client.is_feature_enabled('my_feature'
, 'user_123'
)
if enabled
# Show your feature
else
# Hide your feature
end
const optimizely = require('@optimizely/optimizely-sdk'
);
const optimizelyClient = optimizely.createInstance({ datafile: datafile });
// Evaluate a feature flag
const enabled = optimizelyClient.isFeatureEnabled('my_feature'
, 'user_123'
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
use Optimizely\Optimizely;
// Initialize an Optimizely client
$optimizelyClient = new Optimizely($datafile);
// Evaluate a feature flag
$enabled = $optimizelyClient->isFeatureEnabled('my_feature'
, 'user_123'
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
using OptimizelySDK;
// Initialize an Optimizely client
Optimizely OptimizelyClient = new Optimizely(datafile);
// Evaluate a feature flag
bool enabled = OptimizelyClient.IsFeatureEnabled("my_feature"
, "user_123"
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
import optimizelySDK from '@optimizely/optimizely-sdk'
;
// Initialize an Optimizely client
const optimizelyClientInstance = optimizelySDK.createInstance({ datafile: datafile });
// Evaluate a feature flag
const enabled = optimizelyClientInstance.isFeatureEnabled('my_feature'
, 'user_123'
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
// In AppDelegate.m
#import
// Initialize an Optimizely manager
OPTLYManager *optlyManager = [[OPTLYManager alloc] initWithBuilder:[OPTLYManagerBuilder builderWithBlock:^(OPTLYManagerBuilder * _Nullable builder) {
builder.sdkKey = @''
;
}]];
// Initialize an Optimizely client
[optlyManager initializeWithCallback:^(NSError * _Nullable error, OPTLYClient * _Nullable client) {
// Evaluate a feature flag
bool enabled = [client isFeatureEnabled:@"new_feature"
userId:@"user123"
attributes: nil];
if (enabled) {
// Show your feature
} else {
// Hide your feature
}
}];
import Optimizely
// Initialize an Optimizely client
optimizely = OptimizelyClient(sdkKey: @''
)
try optimizely!.start(datafile: datafile)
// Evaluate a feature flag
let enabled = try optimizely.isFeatureEnabled(featureKey: "my_feature_key"
, userId: "user_123"
)
if enabled {
// Show your feature
} else {
// Hide your feature
}
import com.optimizely.ab.Optimizely;
Optimizely optimizely = Optimizely.builder(datafile).build();
// Evaluate a feature flag
Boolean enabled = optimizely.isFeatureEnabled("my_feature"
, "user_123"
);
if (enabled) {
// Show your feature
} else {
// Hide your feature
}