Enable merge trains in the project under Settings > Merge requests by enabling 'Merge trains' (requires merge pipelines to be enabled first)
Ensure the project has a CI/CD pipeline defined; merge train pipelines run on the simulated merged result of queued MRs in order
Add merge requests to the train using the 'Start merge train' or 'Add to merge train' button in the MR UI, or via API PATCH '/projects/{id}/merge_requests/{iid}/merge' with 'merge_when_pipeline_succeeds=true'
Monitor the train status in the MR list view; each MR shows its position and the pipeline running for its simulated merge commit
If a pipeline fails for an MR in the train, that MR is removed and subsequent MRs are retested against the corrected base
Known gotchas
Merge trains require GitLab Premium or higher; the feature is not available on Free tier projects
Each MR in the train triggers its own pipeline against a speculative merge result; this significantly increases CI minute consumption compared to standard merge pipelines
If the source branch of an MR in the train is force-pushed or updated, the MR is automatically removed from the train and must be re-added
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One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp