Railway breaking changes, updated weekly

Every verified Railway trap in Footgun: changes and behaviors that break code or give wrong results, newest first. Each one has the error you see, the fix, and the date it was last checked. The list updates when the weekly check adds or retires a trap. For the full cause and sources, open the trap, or see all Railway traps.

1. fg-0079· added 2026-09-30· last checked 2026-09-30

   Railway log lines written in the same millisecond come back out of order

   Symptom

   Rows of output are shuffled

   Fix

   Number each line you plan to parse and reassemble by number.

2. fg-0073· added 2026-09-10· last checked 2026-09-10

   New code is not live after 'railway up' because an older redeploy won

   Symptom

   Logs show the previous version's startup lines

   Fix

   Let variable and volume changes settle, then run one railway up on its own and confirm a log line that only the new code prints.

3. fg-0072· added 2026-08-15· last checked 2026-08-15

   Deploying a Railway cron service does not run the job

   Symptom

   Deploy reports SUCCESS with no run in the logs

   Fix

   Test with railway run, which runs the command locally with the service's variables.

4. fg-0080· added 2026-08-01· last checked 2026-08-01· stale, may be out of date

   Railway MCP lists variable names but redacts every value

   Symptom

   valuesRedacted in the list-variables response

   Fix

   Use the CLI from a linked directory when a value must be read or compared.

5. fg-0081· added 2026-07-31· last checked 2026-07-31· stale, may be out of date

   Railway service loses its state file on every redeploy despite STATE_DIR=/data

   Symptom

   History and state are empty after each deploy

   Fix

   Create a volume mounted at that path and confirm the mount in the deploy log.

6. fg-0077· added 2026-07-31· last checked 2026-07-31· stale, may be out of date

   Railway custom domain never gets a certificate after the CNAME was set

   Symptom

   Certificate warning on the custom domain

   Fix

   Copy the current CNAME target and the TXT record from the service's domain settings into DNS, and remove unused custom domains if you hit the cap.

7. fg-0071· added 2026-07-05· last checked 2026-07-05· stale, may be out of date

   A RUN_NOW style variable reruns the job on every Railway redeploy

   Symptom

   The job runs and emails again after every deploy

   Fix

   Delete the flag right after the manual run. Audit services for leftover flags.

8. fg-0074· added 2026-07-05· last checked 2026-07-05· stale, may be out of date

   Node service on Railway crashes with 'Premature close' or undici errors at boot

   Symptom

   Premature close on token or API fetches

   Fix

   Pin the Node version in package.json.

9. fg-0075· added 2026-06-12· last checked 2026-06-12· stale, may be out of date

   Railway agent tool says the variable was updated, but the deployed value never changes

   Symptom

   Agent reports applied or staged for deployment

   Fix

   Set variables with the CLI and verify in the runtime log, not in the agent's reply.