I made a heatmap diff viewer for code reviews
Details
- External ID
- 45760321
- Source
- HN
- Company
- —
- Product
- I made a heatmap diff viewer for code reviews
- Website domain
- 0github.com
- Launched
- Oct. 30, 2025
- Cohort
- —
- Upvotes
- 265
- Upvotes percentile
- 0.9811320754716981
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
0github.com is a pull request viewer that color-codes every diff line/token by how much human attention it probably needs. Unlike PR-review bots, we try to flag not just by "is it a bug?" but by "is it worth a second look?" (examples: hard-coded secret, weird crypto mode, gnarly logic, ugly code).To try it, replace github.com with 0github.com in any pull-request URL. Under the hood, we split the PR into individual files, and for each file, we ask an LLM to annotate each line with a data structure that we parse into a colored heatmap.Examples:https://0github.com/manaflow-ai/cmux/pull/666https://0github.com/stack-auth/stack-auth/pull/988https://0github.com/tinygrad/tinygrad/pull/12995https://0github.com/simonw/datasette/pull/2548Notice how all the example links have a 0 prepended before github.com. This navigates you to our custom diff viewer where we handle the same URL path parameters as github.com. Darker yellows indicate that an area might require more investigation. Hover on the highlights to see the LLM's explanation. There's also a slider on the top left to adjust the "should review" threshold.Repo (MIT license): https://github.com/manaflow-ai/cmux
Enrichment
- Theme
- git and repository workflow tools
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Hobby / open-source project
- Normalized one-liner
- heatmap visualization for code reviews
- Manually corrected
- False
Could you build this?
Yes A web-based diff viewer integrating with GitHub PRs that applies static rules or an LLM call to color-code attention hotspots can be vibe-coded in days.
Discussion
20 comments analyzed.
Competitors mentioned: Claude Code for code review and understanding, GitHub's native code review tools
Concerns raised: Excessive energy consumption and climate impact for minimal utility, Inaccurate highlighting - misses important deletions and deleted code, Highlights test code over material changes needing review, Highlights unchanged lines incorrectly, LLM lacks context for familiar codebases - reviewers know code better
Feature requests: Dark theme with prefers-color-scheme: dark support, Remove GitHub sign-in requirement for local repository support, CLI-only version for easier integration, Respect inline comments explaining deprecations or intentional choices, Better support for understanding deleted code and removals
Competitors
Other products that read as similar to this one — 68 launches clear the similarity bar, closest 8 shown.
Attention rank: #1 of 69 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Looks like the first mover among its competitors.
- Diffswarm · hn · 2026-01-06 · 8 upvotes · similarity 0.54
- MyGitDiff · github · 2026-09-10 · 7 upvotes · similarity 0.47
- Haystack · hn · 2026-05-18 · 45 upvotes · similarity 0.42
- Deff · hn · 2026-02-26 · 120 upvotes · similarity 0.41
- Gitwall for Mac · ph · 2026-09-12 · 3 upvotes · similarity 0.41
- Sidenote · hn · 2026-07-05 · 9 upvotes · similarity 0.40
- GitHub "Lines Viewed" extension to keep you sane reviewing long AI PRs · hn · 2026-02-13 · 40 upvotes · similarity 0.40
- Code Review Enviornment for the Modern Era · hn · 2026-07-06 · 5 upvotes · similarity 0.40
Other launches for this product
- No other launches for this product.
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