LightMerge: Accelerating Multi-Feature Branch Integration on Ctrip’s Code Platform

LightMerge is a tool built by Ctrip’s code platform to accelerate the integration of multiple feature branches. It was created to solve the problems that arise when several feature branches need to be merged into a single integration branch, such as conflict detection, repeated manual testing, and inefficient release coordination.

Ctrip follows a feature‑branch development model with a protected master branch that serves as the core integration branch. Developers create separate feature branches (e.g., F01, F02, F03) and submit Merge Requests to merge into master after self‑testing.

When many feature branches are ready, several issues can occur: overlapping changes to the same files cause merge conflicts, sequential merges may introduce regressions, and each merged branch may require a separate test environment, leading to resource waste.

LightMerge automatically monitors protected branches, merges any two or more selected feature branches, and instantly notifies stakeholders of any conflicts. It continuously re‑merges and checks branches whenever changes occur, integrating with Sonar static analysis and code review processes.

The tool provides key capabilities: automatic conflict alerts, multi‑branch auto‑merge, flexible selection of branches to integrate, efficient identification of the largest set of compatible branches, simple configuration, CI support, and tight integration with Merge Requests.

In practice, LightMerge is used in a recommended multi‑feature release workflow: developers submit Merge Requests, the integration team uses LightMerge to test combinations of feature branches, and only the subset that passes integration and CI is accepted for release, while conflicting branches are rejected.

By automating conflict detection, merging, building, packaging, and deployment, LightMerge reduces the manual, repetitive work traditionally required for large‑scale integration, making the release process faster and more reliable.

LightMerge has already been adopted by many Ctrip project teams as an integration accelerator, and the article encourages broader adoption across the organization.