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Kottayam Online Judge
KOJ
A contest platform and problem archive for IIIT Kottayam. Students browse problems, enter contests, submit code, and follow verdicts.

How the judge works
- 01RecordSubmission and judge job are written to Postgres in one transaction.
- 02RunA worker claims the job and runs submitted code in a restricted Docker container.
- 03ReturnThe verdict is saved and status updates reach the web app over SSE.
Workers use expiring leases and heartbeats; fencing prevents a stale attempt from overwriting a newer verdict.





