Alternatives
Products that do what Great Spectations, the Spec Checker does
I've worked on several projects writing and implementing specifications (particularly CLN): I've found the specs I write are much better when I quote them in the implementation, so I can see what implementers need to know. Also, when specs change in development, it's almost trivial to find where to update the code. This project is a formalization of my various hacky scripts which ensure the requirements are accurately quoted, and give coverage if any are missing. Not a major Opus, but I hope someone else finds it useful!
- 1ST
We're a couple of software engineers who believe that to build great software you need to write good tests, but we also sympathise when engineers say things like: - "Writing tests was too time consuming on my tight schedule", or - "Unit tests don't catch enough bugs, so they're useless", or - "I've inherited a legacy code base without tests and have no idea where to start" To tackle this we're building Symbolica (https://www.symbolica.dev), a symbolic code executor [1], that lets you run your code for all possible inputs. This means you can do things like: - Assert properties about…
2021
- 2IM
Hey HN! I made a completely open sourced alternative to Weights and Biases with (insert cringe) blazingly fast performance (yes we use rust and clickhouse) Weights and Biases is super unperformant, their logger blocks user code... logging should not be blocking, yet they got away with it. We do the right thing by being non blocking. Would love any thoughts / feedbacks / roasts etc
2025 · github.com
- 3TJ
After 6 years of coding almost every day, I'm finally ready to show HN. There's a lot going on here, looking forward to your guy's feedback.
Jul 2026 · jaclang.org
- 4IB
You know that old TI calculator you used in high school, then put in a box and forgot about? Have you ever wished you had an operating system for your calculator with preemptive multitasking, dynamic memory management, a tree filesystem conforming to the FHS, and all the comforts of Unix? Well, good news: that's totally a thing that exists. I've been working on my kernel for about three and a half years now and I'm looking for new contributors to help out. It's written entirely in z80 assembly, and it's both challenging and fun to work on. There's an IRC channel for contributors or people…
2014
- 5CO
First tutorial to date. Writing your first C program, includes a link at the bottom with a detailed look at printf() as optional reading. I would love some feedback, as I intend writing up a lot of dev articles for people to learn from : www.xanthu.com/first-c-program
2013
- 6EC
I participated in the Nvidia + Vercel 2 hour hackathon in SF tonight, and built something I've wanted, but hadn't tried building. I implemented an MCP Server and VS Code extension to allow Claude Desktop to place breakpoints, step through code, and execute expressions (assuming language support). So you can ask it a question that requires actually stepping through the code and now it can actually do that - check values for you, etc. It's _definitely_ not perfect. Have improvements? Please make a PR!
2025 · github.com
- 7MP
My weekly(ish) video logs tracking my progress of building a completely sound statically typed language and structural editor. The motivation is to make lots of invalid programs unrepresentable.
2022 · petersaxton.uk
- 8TS
Code review is the new bottleneck. "Tests passing" is no longer sufficient to trust the changes, and the (human) cost of evaluating the quality and robustness of new agent-written contributions is skyrocketing. We built Topos to evaluate code quality based on the structural properties of the programs themselves. We map your files to graphs (AST, CFG, CPG, MDG) and calculate metrics that can characterize how simple, composable, or secure your programs are. Agents can use this tool as they write and optimize based on your preferences. And yes, the inspiration for the repository is from…
Jun 2026 · krv.ai
- 9IB
The main goal of this was to be able to not just run multiple Claude Code sessions at once, but actually manage them and keep track of what I was doing. Sometimes this is multiple attempts on the same task, sometimes I work several tasks at once. Really I was just sick of twiddling my thumbs waiting for the coding agent to finish, and I wanted it to be easy to work on/review/test another change while I waited.
2025 · github.com
- 10BP
We got tired of not being able to accurately answer "When will this be done?" and "Will anyone be required to work overtime on the current schedule?", or spending too much time in meetings and standups trying to answer those questions. Just opened up for beta. Would love some opinionated developers to guide future improvements (or feedback on the general idea).
2022 · projectburndown.com
- 11LS
Earlier this year, I took a month to reexamine my coding habits and rethink some past design choices. I hope to rewrite and improve my FOSS libraries this year, and I needed answers to a few questions first. Perhaps some of these questions will resonate with others in the community, too. - Are coroutines viable for high-performance work? - Should I use SIMD intrinsics for clarity or drop to assembly for easier library distribution? - Has hardware caught up with vectorized scatter/gather in AVX-512 & SVE? - How do secure enclaves & pointer tagging differ on Intel, Arm, & AMD? - What's…
2025 · github.com
- 12YA
I must say I was encouraged to post my project here when I saw the positive response to this post: http://news.ycombinator.com/item?id=3780731 Before you make any comments, please keep in mind that the project is written for fun. I'm not forcing anyone to use it. In fact, nobody should use the current unstable version in a serious project. Here is the link: http://github.com/bsg/libserv Please share your thoughts. All criticisms are welcome, even the harsh ones. p.s. The project is still a work-in-progress.
2012
- 13WT
I've been lurking on HN for years. You know the drill: interesting headline, 200+ comments, you dive in thinking "I'll just skim for 5 minutes"... and an hour later you're 36 chambers deep in a thread about memory allocation patterns in Postgres and you've completely forgotten what the original article was about. I don't just want a "summary" (which usually just shortens the noise). I want the meta-consensus: "What is the actual trade-off being debated? Who is winning the argument? Why does this matter?" So I built HNSignals. Think of it less like a "summarizer" and more like a Chief of…
Jan 2026 · hnsignals.com
- 14SH
This is my hobby C compiler project. Decided to publish the code today, as it finally compiled itself. The readme on the linked GitHub page has a bit of information on how it works. I wrote the thing for fun, but if anyone gets a better understanding of the dark corners of C because of it, I am happy.
2022 · github.com
- 15NT
I built a CLI tool that turns codebases and PRs into diagrams so you can quickly understand how things fit together. Originally made it because I couldn't follow my own AI-generated repos. Just shipped a big update: - Switched from D2 to Mermaid for rendering - Tree-sitter AST parsing + agentic flow instead of raw LLM calls. ~50x faster. - Works on any GitHub repo or PR, not just local - Dropped the web frontend, it's just a CLI now - Published as a pip package Still a ton to improve and I'm building fast. Feedback, issues, PRs all welcome.
Feb 2026 · github.com
- 16LI
Hi HN! I kept hearing about Lisp and why it was special but didn't have a great place to start. I wanted something self-contained that helped me develop intuition rather than fluency. My hope is this is helpful for casual programmers, professionals from other fields who interact with code, or engineers who haven't had much exposure to interpreters or compilers. Hope this helps anyone else who's curious about getting a sense of Lisp and what makes it special with a limited time investment! Feedback or other cool Lisp things welcome :)
2022 · github.com
- 17IB
Hi HN, I've been working on this for a while and it was hard to decide when to stop, either on the way information is presented or when to stop with adding entries. It's not meant as a blog, but rather as a reference that keeps growing. Link: https://thehardparts.dev Currently I've created 4 main section: - Failure Modes: ways project go wrong - Red Flags: early signals that are worth taking seriously - Tech Decisions: common and not so common trade-offs for hard choices - Playbooks - guided approach for situations that repeat I've also focused on creating links between them to…
Apr 2026 · thehardparts.dev
- 18IA
Hey HN, I am making an 8-Bit CPU in Logisim and blogging about it.t's nothing fancy, really simple, unoptimized dumb CPU for sake of learning. I am no electrical engineer, I am just a self-taught dude who has programming as a hobby and wanted to dive deeper into abstractions. So here it is, so far I wrote 2 parts: [links redacted] I welcome any and all critique and feedback, as I can be wrong about everything for sure.
2017
- 19LB
Howdy friends! Tell me if this is an atrociously terrible idea - I've been working on building a leetcode for clientside devs so we can practice React and Javascript interview questions in a more concise way, I call it clientside.dev I just finished a beta version of it yesterday and plan on releasing it with many more problems on Jan 1st but it's there if you wanna play with it open to any ideas / feedback however mean or nice it may be :)
2022 · vacation-call-335691.framer.app
- 20HT
Fun little project, had Gemini 2.5 Pro summarize HN's top 30 each hour, both the stories and comment sections. Pretty impressed with Gemini 2.5. It's probably the first model other than Claude 3.7 Sonnet where I actually find the output readable. I normally use 3.7 Sonnet for coding, but used Gemini for the codegen on this one as well. Was pretty impressed! Using Cursor, it seemed to instruction-follow better than Claude generally does, and remain lucid during very long agent sessions. Thanks for your feedback!
2025 · tinysums.ai
- 21OC
I am very new to this. I have tried to follow to follow your guidelines, but I'm not sure if I have got it right. The URL point to release notes which give a brief overview of the project including its history. As production code, this is still early stage - but I think it works well enough to be useful to people other than myself.
2023 · github.com
- 22MA
Hey any astrophysicist reading hn there? Was sick in august (yeah isn't that nice) and made a small python fits table viewer for the terminal with textual. It would be great to have people try it so if you find any issue I can improve it. If you have no FITS file but would like to try regardless there are some test file in `/test`. Ciao!
2024 · github.com
- 23IB
I’ve spent the last 2.5 months building a product that runs LLM-powered code reviews on my pull requests — and I just launched it. The tool is built specifically for solo developers. You install it on your repo, trigger a scan by creating a pull request, and it leaves structured review comments using OpenAI under the hood. Funnily enough, I used the dev version of this app to review its own pull requests while building it. It helped me spot bugs, simplify structure, and keep quality high — all with minimal need for another human in the loop. Things I want to try out in the next months : -…
2025 · codii.dev
- 24IB
After fine-tuning GPT for a personal project, I realized how tedious it is to write plain text in a massive JSON file. That's why I built this app for my own use, and I want to see if others could benefit from a tool like this as well ;)
2024 · finetuna-ui.com
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