I believe that injecting the variable only with Github automatic build is and not injecting during "Deploy Latest" is inconsistent. Hope you can fix this.

From conversation with Railway AI:

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The issue: When you use the "Deploy latest" command, Railway isn't automatically injecting RAILWAY_GIT_COMMIT_SHA as a build argument. This is a Railway platform limitation — the variable is available as an environment variable at runtime, but it's not automatically passed as a Docker build ARG.

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Bottom line: This is a Railway platform gap. You should open a support thread at station.railway.com requesting that RAILWAY_GIT_COMMIT_SHA be passed as a Docker build ARG automatically. In the meantime, one of the workarounds above may unblock you.

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