Yansu, Serious Coding
Details
- External ID
- 45826492
- Source
- HN
- Company
- —
- Product
- Yansu, Serious Coding
- Website domain
- twitter.com
- Launched
- Nov. 5, 2025
- Cohort
- —
- Upvotes
- 6
- Upvotes percentile
- 0.27074235807860264
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
We been helping mid-market companies for the past 1.5 years and finally ready to share the internal platform publicly.Yansu (严肃) is a AI coding platform that use spec + TDD to build complex software projects. It is more like a SOP than coding agent. We focus on understanding requirements and checking outcomes against those requirements while iterating the code based on the tests.Yansu tries to learn as much tribal knowledge as possible. These are things you don’t write down in google doc or Notion. Yansu absorbs these knowledge by continuously talking to users and distilling learning from them.It's as if a spec + TDD platform had a baby with character.ai.Why care about requirements? B/c 80% of any software development is understanding requirements and what exactly we want to build. We also focus on outcomes, the only thing that matters. We deliver satisfying outcomes by simulating scenarios and generating tests based on those scenarios. Our agents take that tedious testing part of the code away from others.We prioritize accuracy over latency/cost, using a mixture of agents (not limited to CC, codex, and etc) to get the job done. We then run through continuous-testing-generating pipelines until all things pass.What does Yansu mean? “Serious” in Chinese. Just like my favorite artist, Rene Magritte, painting in his kitchen in a suit. I want to give my coding respect and care.Our goal is to level people up from IC to tech leads, to work on the high leverage work of planning, validating, and educating.We made a launch video to celebrate human work that builds on all of the creative minds before us. Shoutout to CinemaSings for making this happen.Enjoy the video (linked in the tweet) and check out Yansu.
Enrichment
- Theme
- coding agents and developer utilities
- Vertical
- Education
- Function
- Vertical SaaS
- Audience
- B2C
- AI stance
- Not AI
- Project type
- Commercial product
- Normalized one-liner
- coding practice platform
- Manually corrected
- False
Could you build this?
Partial A basic LLM wrapper for generating tests and specs is easy to vibe-code, but an enterprise-grade automated TDD platform requiring sandboxed deterministic code execution and strict SOP validation needs sophisticated agentic orchestration infra.
What it would actually take: The architecture requires an orchestration engine (e.g., Temporal or custom state machine) coordinating LLM agents across specification, test-generation, and implementation stages. It needs secure microVM or Docker-based sandboxes (like Firecracker or Docker-in-Docker) to execute arbitrary tests safely and verify builds deterministically across different repositories. Deep expertise in systems engineering, AST manipulation, and reproducible build pipelines is required beyond simple prompting.
Discussion
2 comments analyzed.
Competitors
Other products that read as similar to this one — 15 launches clear the similarity bar, closest 8 shown.
Attention rank: #14 of 16 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Looks like the first mover among its competitors.
- Yansu · ph · 2026-05-25 · 341 upvotes · similarity 0.55
- jj-benchmark · hn · 2026-03-12 · 5 upvotes · similarity 0.37
- 1v1 coding game that LLMs struggle with · hn · 2026-03-06 · 29 upvotes · similarity 0.37
- I Built a Debugging Challenge for the AI Coding Age · hn · 2026-05-25 · 5 upvotes · similarity 0.35
- Baize · github · 2026-09-12 · 71 upvotes · similarity 0.35
- Monozukuri · github · 2026-09-09 · 11 upvotes · similarity 0.34
- CodeKairo · ph · 2026-09-22 · 1 upvotes · similarity 0.32
- QVAC SDK, a universal JavaScript SDK for building local AI applications · hn · 2026-04-09 · 30 upvotes · similarity 0.32
Other launches for this product
- No other launches for this product.
Same idea, different domain
Nobody's really built a vertical saas tool for Insurance yet.