CodeViz
A diagram editor that understands your code (YC S24)
Details
- External ID
- 46112279
- Source
- HN
- Company
- —
- Product
- —
- Website domain
- —
- Launched
- Dec. 1, 2025
- Cohort
- —
- Upvotes
- 5
- Upvotes percentile
- 0.10400763358778627
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
Hey HN, we’re Will and Liam, founders of CodeViz (YC S24). We’re building a VS Code extension that reads your code and generates editable architecture diagrams (C4, UML). It’s mostly used by teams to build shared context, agree on technical decisions, and visualize PRs.Here’s a recorded demo: https://youtu.be/Jh3wkrCj_WQ You can try the VS Code extension here: https://marketplace.visualstudio.com/items?itemName=CodeViz....It’s free for 10 generations/month (no signup). Then, we have a $19/month plan for unlimited diagram generation and $50/month plan for live collaboration.We launched a v1 last year to help engineers read code faster (https://news.ycombinator.com/item?id=41393458), but no one actually used CodeViz for that. Users were taking screenshots of our diagrams for presentations and architecture reviews. We rebuilt CodeViz to shift from a passive viewer to a collaborative editor for modeling specific flows, using C4 and UML standards.This required a major change in our technical approach. In our original version, we relied on static analysis, building stack graphs with tree-sitter for ~15 languages (using language servers as teachers). While technically precise, these graphs were way too noisy and didn’t map to human abstractions.We now use an adaptation of gemini-cli to read the codebase, generate C4 + Activity PlantUML diagrams, and link nodes directly to source code. These are parsed into a diagram editor that we built with ReactFlow. You can click to expand nodes into lower levels of abstraction, ask an AI assistant to visualize a specific flow, or import PRs from GitHub.CodeViz is in active development, all honest feedback is much appreciated! Our roadmap is largely focused on tools for working in teams, so we’d also love to hear about your problems with architecture reviews and onboarding.
Enrichment
- Theme
- Claude integrations and coding agents
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- AI feature
- Project type
- Commercial product
- Normalized one-liner
- diagram editor that understands code
- Manually corrected
- False
Could you build this?
Partial The VS Code extension and interactive diagramming canvas are vibe-codeable, but robust static analysis to extract architectural diagrams and track semantic changes across large multi-language codebases is difficult.
What it would actually take: The architecture requires a language server or Tree-sitter AST parser coupled with an LLM reasoning layer to map code dependencies into C4 model abstractions. The core difficulty lies in disambiguating service boundaries, call graphs, and dynamic dispatch accurately without generating messy, unreadable diagram topologies or hallucinated connections.
Discussion
2 comments analyzed.
Competitors
Other products that read as similar to this one — 129 launches clear the similarity bar, closest 8 shown.
Attention rank: #122 of 130 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 26 days after the earliest competitor.
- Code Graph View · ph · 2026-09-22 · 1 upvotes · similarity 0.52
- Dynamic code and feedback walkthroughs with your coding Agent in VSCode · hn · 2025-11-06 · 48 upvotes · similarity 0.49
- Nogic · hn · 2026-01-13 · 135 upvotes · similarity 0.48
- CodeViz · ph · 2026-09-13 · 2 upvotes · similarity 0.46
- Noodles · hn · 2026-02-24 · 6 upvotes · similarity 0.45
- Whiteboard (YC W26) · hn · 2026-09-24 · 421 upvotes · similarity 0.44
- I built a visual node system for CI/CD that supports GitHub Actions · hn · 2026-02-10 · 18 upvotes · similarity 0.44
- Noodles · hn · 2026-02-06 · 10 upvotes · similarity 0.44
Other launches for this product
- No other launches for this product.
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