Sandboxed · Docker · BullMQ
A coding judge that tells you the truth.
Submit your solution. It compiles in Docker, runs against testcases, and you get a verdict — no ambiguity, no excuses.
exec-d — submission result
Compile✓ OK
Testcase 1 / 5✓ 14ms
Testcase 2 / 5✓ 9ms
Testcase 3 / 5✓ 11ms
ACCEPTEDRuntime 11ms · 2048KB
How it works
Four steps from keystroke to verdict.
01
Write
Python, C++, Java, or Node.js — pick your language and write your solution.
02
Queue
BullMQ picks up the job instantly and hands it to the next free worker.
03
Sandbox
Your code runs inside a locked Docker container — no network, no tricks.
04
Verdict
Per-testcase results with real runtime and memory from container stats.
30 problems ready to go
Classic competitive programming challenges. No account needed to browse.