A Jev engineer skips CI by judging changes on shadow traffic
A Jev engineer hasn't waited on a CI pipeline in three months: each change runs on a mirrored copy of real traffic, Jev scores intent request by request rather than exact matches, and passing changes go live with a 200 ms rollback armed.
A Jev engineer hasn’t waited on a CI pipeline in three months, and his changes still reach production faster and safer than the rest of the team’s He never sped the pipeline up. He routed around it, letting every change prove itself on live traffic users never see. > SHADOW - each change runs beside production on a mirrored copy of real traffic > JUDGE - the Jev system compares both outputs request by request, never by averages > SWAP - a change that matches or beats live behaviour goes in, with a 200 ms rollback armed CI was built for a world where real traffic was too risky to touch, so it tests against guesses about what users do. Shadow traffic removes the guess. The new code sees exactly what users send, and its answers simply never reach them. The comparison is the hard part. Two outputs can differ and both be right, so Jev scores intent instead of exact matches. Most changes clear in minutes. The ones that fail get caught on the exact request that broke them, input attached. The armed rollback is what makes it safe. One bad response and the old path is back before the next request lands. His team still writes tests. They just stopped treating a green checkmark as proof that real users will be fine. His full setup, from the traffic mirror to the rollback trigger, is written up in the article attached here.
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