Head to head
Aider vs Devin
Comparing 5 documented Aider incidents against 9 for Devin.
What these records show
Devin has the lower average severity among the incidents collected here (4.0 vs 2.4 for Aider and Devin, from 5 and 9 incidents). These records can't establish which agent is safer: counts reflect how widely each is used and how often people report failures, not a failure rate.
| Metric | Aider | Devin |
|---|---|---|
| Documented incidents | 5 | 9 |
| Average severity | 4.0 | 2.4 |
| Critical | 0 | 0 |
| High | 0 | 0 |
| Source checked | 2 | 9 |
Severity at a glance
Failure modes
The incidents behind these numbers
Aider
6.0Aider leaks model-provider API keys to child processes spawned via /run, /test, lint commands, and /git4.0Aider's headless `--message` mode silently swallows slash commands (`/model`, `/ask`, `/architect`) and exits 0 having done nothing4.0Aider exits with code 0 after a fatal API connection failure, masking hard failures as successful headless runs3.0Aider's unified-diff coder silently drops the partial-application warning when one hunk succeeds and another fails3.0Aider silently discards a model's correct diff response as "no tracked changes" when it guesses the wrong edit format
Devin
5.0Devin replaced entire medical website with unrelated renal care site3.0Devin CI workflow caused 836-comment spam storm on single PR2.0Devin built 13,600-line app with build failure instead of lean campaign dashboard2.0Devin PR broke ledger list API and created buckets on deleted resources2.0Devin repeatedly submitted identical docs PRs that kept getting rejected