Head to head
Aider vs Devin
Comparing 4 documented Aider incidents against 10 for Devin.
Verdict
Devin has the lower average failure severity (3.9/10 vs 4.5/10), making it the statistically safer choice of the two — though both agents have documented critical incidents.
| Metric | Aider | Devin |
|---|---|---|
| Documented incidents | 4 | 10 |
| Average severity | 4.5 | 3.9 |
| Critical | 0 | 1 |
| High | 0 | 0 |
| Verified | 1 | 10 |
Severity at a glance
Failure modes
The incidents behind these numbers
Aider
4.8Aider exits with code 0 after a fatal API connection failure, masking hard failures as successful headless runs4.6Aider silently discards a model's correct diff response as "no tracked changes" when it guesses the wrong edit format4.4Aider's headless `--message` mode silently swallows slash commands (`/model`, `/ask`, `/architect`) and exits 0 having done nothing4.2Aider's unified-diff coder silently drops the partial-application warning when one hunk succeeds and another fails
Devin
10.0Devin replaced entire medical website with unrelated renal care site5.8Devin CI workflow caused 836-comment spam storm on single PR5.0Devin built 13,600-line app with build failure instead of lean campaign dashboard3.4Devin PR broke ledger list API and created buckets on deleted resources3.4Devin attempted to build entire Figma clone from scratch — 3 rejected attempts