Go SDK
Go-SDK - 2.6.0
Holdout Targeted Delivery Exclusion Holdouts can now be configured to exclude Targeted Delivery rules, so users held out of experiments still receive their Targeted Delivery experiences. This gives you a cleaner measure of experiment impact without holding users back from ongoing rollouts.
Go-SDK - 2.5.0
July 14, 2026 \[FSSDK-12369] Add local holdouts support to Go SDK by @Mat001 in https //github. com/optimizely/go-sdk/pull/451 https //github.
Go-SDK - 2.4.0
May 4, 2026 Feature Rollout Added support for Feature Rollouts, a new experiment type combining Targeted Delivery simplicity with A/B test measurement capabilities. Feature Rollouts enable progressive rollouts with full impact analytics, metric tracking, and confidence intervals.
Go-SDK - 2.3.1
January 22, 2026 \#whats-changed \[FSSDK-12037] Exclude CMAB experiment from UPS by @Mat001 in https //github. com/optimizely/go-sdk/pull/433 https //github.
Go-SDK - 2.3.0
December 12, 2025 \#new-features Holdout Support Added holdouts support with datafile parsing and full decision logic for excluding users from experiments ( #422 https //github. com/optimizely/go-sdk/pull/422 ) Holdout Impression Events Added impression event handling for holdouts with proper rule type "holdout" metadata ( #428 https //github.
Go-SDK - 2.2.1
\#221---october-24-2025 \#bug-fixes CMAB Cache Size Alignment Increased CMAB default cache size from 1000 to 10000 to align with ODP segments cache size for consistency ( #425 https //github. com/optimizely/go-sdk/pull/425 ) Bucketing Precision Fixed float32 precision error that caused incorrect bucketing for specific users ( #423 https //github.
Go-SDK - 2.2.0
\#220---september-30-2025 \#new-features CMAB (Contextual Multi-Armed Bandit) Support Added support for CMAB experiments with new configuration options and cache control ( #399 https //github. com/optimizely/go-sdk/pull/399 , #401 https //github.
Go-SDK - 2.1.0
\#210---november-8-2024 \#enhancements Batch Processing for User Profile Service (UPS) Added support for batch processing in decideAll and decideForKeys , enabling more efficient handling of multiple decisions in the User Profile Service. ( #394 https //github.
Go-SDK - 1.8.5
Fixed a bug in the HTTP Requester logging. Now correct error message is logged.
Go-SDK - 1.8.4
We updated our README. md and other non-functional code to reflect that this SDK supports both Optimizely Feature Experimentation and Optimizely Full Stack.
Go-SDK - 1.8.3
Add option to set custom http. Client on HTTPRequester.
Go-SDK - 1.8.2
Add additional validation for numeric attribute types when building an event object. ( #341 https //github.
Go-SDK - 1.8.1
Add validation for user attribute types when building an event object. Only allow primitive types ( #339 https //github.
Go-SDK - 1.8.0
Add a set of new APIs for overriding and managing user-level flag, experiment and delivery rule decisions. These methods can be used for QA and automated testing purposes.
Go-SDK - 1.7.0
Add new public properties to OptimizelyConfig . ( #322 https //github.
Go-SDK - 1.6.1
\- Fix issues for decision variables and reasons (\[#309]\( https //github. com/optimizely/go-sdk/pull/309 https //github.
Go-SDK - 1.6.0
\> Introducing a new primary interface for retrieving feature flag status, configuration and associated experiment decisions for users (\[#304]\( https //github. com/optimizely/go-sdk/pull/304 https //github.
Go-SDK - 1.5.1
\- Add "enabled" field to decision metadata structure (\[#301]\( https //github. com/optimizely/go-sdk/pull/301 https //github.
Go-SDK - 1.5.0
\- Correct logic for rollout service (\[#296]\( https //github. com/optimizely/go-sdk/pull/296 https //github.
Go-SDK - 1.4.0
\- Add MatchRegistry for custom match implementations. (\[#286]\( https //github.
Go-SDK - 1.3.0
\- Add support for JSON feature variables (\[#250]\( https //github. com/optimizely/go-sdk/pull/250 https //github.
Go-SDK - 1.3.0-beta3
\- Provide syncronization for Notification Center Cache (\[#273]\( https //github. com/optimizely/go-sdk/pull/273 https //github.
Go-SDK - 1.3.0-beta2
\- Bring back old constructors for static manager (\[#271]\( https //github. com/optimizely/go-sdk/pull/271 https //github.
Go-SDK - 1.1.3
\## Bug Fix \- logger not set for httpDispatcher \[#254]\( https //github. com/optimizely/go-sdk/pull/254 https //github.