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A small tool that parses C declarations and outputs a simple visual representation at each stage, as it encounters arrays, pointers or functions.

The program uses a table-driven lexer and a hand-written, shift-reduce parser. No external dependencies apart from the standard library.

LeetcodeWrapped is a web application that allows users to analyze their LeetCode problem-solving history, including statistics on the problems they've solved, the languages they've used, and their performance over time.

Hey everyone I’ve been on my FIRE journey for a while and got tired of juggling spreadsheets, brokers, and bank apps — so I built WealthYogi, a privacy-first net worth tracker focused on clarity and peace of mind. Why Like many FIRE folks, I was juggling spreadsheets, bank apps, and broker dashboards — but never had one clear, connected view of my true net worth. Most apps required logins or shared data with third parties — not ideal if you care about privacy. So I built WealthYogi to be: Offline-first & private — all data stays 100% on your device Simple — focus purely on your wealth trajectory, not budgeting noise Multi-currency — 23 currencies, supporting GBP, USD, EUR, INR and more What it does now * Tracks your net worth and portfolio value in real time * Categorises assets (liquid, semi-liquid, illiquid) and liabilities (loans, mortgages, etc.) * Multi-currency support (GBP, USD, EUR, INR and more) * Privacy-first: all data stays 100% on your device * 10+ Financial Health Indicators and Personalised Finance Health Score and Suggestions to improve * Minimal, distraction-free design focused purely on your wealth trajectory Planned features (already in development) Real-time account sync Automatic FX updates Import/Export support More currency account types Debt tracking Net worth forecasting Pricing Free Trial for 3 days. One time deal currently running till 10th December. Monthly and Yearly Subscriptions available.

Would love your feedback 1. Try the app and share honest feedback — what works, what feels clunky 2. Tell us what features you’d love to see next (especially FIRE-specific ideas!) 3. Share how you currently track your net worth — spreadsheet, app, or otherwise

Here’s the link again: WealthYogi on the App Store (https://apps.apple.com/us/app/wealthyogi/id6753881658) WealthYogi on the Android (https://play.google.com/store/apps/details?id=com.dyogi.weal...) Demo (https://youtu.be/KUiPEQiLyLY)

I am building this for the FIRE and personal finance enthusiasts, and your feedback genuinely guides our roadmap. — The WealthYogi Team hello@datayogi.io

I'm a solo dev and guitarist who got frustrated juggling separate apps for tracking gear, practicing, and collaborating.

What it does:

1) Smart inventory – Add your guitars, get auto-filled specs from ~1,000 models in the database. Track woods, pickups, tunings, string changes, photos.

2) AI practice sessions – Generate personalized tabs and lessons based on your practice history. Rendered with VexFlow notation.

3) Session Mode – Version-controlled music collaboration (think Git for audio). Fork tracks, add layers, see history, merge contributions.

4) Musical tools – Tuner, metronome, scale visualizer, chord progressions, fretboard maps. Last.fm integration for tracking what songs you're learning.

5) Guitar RPG – Fight monsters by playing real guitar notes. Web Audio API detects your playing. 300+ hand-crafted lessons from beginner to advanced.

What you can try without signing up: 1) The RPG demo is completely free, no account needed: https://openfret.com/game — just click "Start Battle" and play. It's capped at level 10 but gives you a real feel for the note detection.

The full platform (inventory, AI practice, sessions) requires Discord or magic link auth.

Current state: Beta. Core features work, actively adding content. The RPG has 300+ lessons done with more coming. Full game is $10 one-time, everything else is free.

Why I built it: I have a basement music setup and wanted one place to track when I last changed strings, get practice material that adapts to what I'm working on, and collaborate without DM'ing WAV/MP3 files.

Tech: Next.js (T3), Web Audio API for pitch detection, VexFlow for notation, Strudel integration for algorithmic backing tracks, Last.fm API.

Happy to answer questions about the AI tab generation, note detection, or the Git-style collaboration model.

Hi everyone, I built FuseCells, a minimalistic logic puzzle game where every level is handcrafted (no procedural generation). It started as a personal challenge to design a clean rule-set and scale it to thousands of puzzles without losing difficulty balance.

What’s unique: • 2,500 handcrafted levels across multiple grid sizes • Deterministic logic — no guessing required • A rule system inspired by constraint-solving and path-finding concepts • Daily challenges and global progress tracking • Fully built as a solo dev project

Technical notes for those curious: • Level generation tools I wrote validate solvability using a custom constraint solver • Difficulty is estimated via step-count of the solver • The game is optimized to run smoothly on low-end devices • Designed first for iOS, now fully adapted for iPad as well

I’d love feedback from puzzle lovers, game designers, and anyone interested in handcrafted logic design. Here’s the App Store link: [inserați linkul]

Thanks for reading — happy to answer any technical questions!

`cargo install tascli`

Manages your own task and records in the terminal simply with tascli - tiny, fast and simple.

Hello HN! We're a team of three building a new kind of web-based markdown editor.

There are many editors out there, so one is spoiled for choice, but Kraa's approach is a little different. It's trying to be both a minimal and distraction-free experience while being feature-rich and allowing for tons of use cases.

What Kraa's good for:

- Distraction-free writing & reading (minimal UI, performant, styling logic completely separated from the editing experience)

- Quick sharing of any written text – compared to many other writing tools, your content can be easily shared just by posting a link and giving 'read' or 'edit' access (we also have password-protection)

- Real-time chat / communities – Kraa has some unique features around real-time editing and our Chat widget allows for a frictionless chat experience. No send button.

- Kraa works well on mobile (though dedicated apps are planned)

---

Demo examples (all live, no login needed):

Blog article: https://kraa.io/kraa/examples/echolibrary

Long-form story: https://kraa.io/kraa/examples/insidekick

Magazine: https://kraa.io/weeklyinspiration

Kraa is built on top of ProseMirror (and TipTap) and Svelte.

You don’t need an account to try Kraa. We’d really appreciate your thoughts and feedback!

Runbox recreates core container features without relying on existing runtimes or external libraries. It uses namespaces, cgroups v2, and seccomp to create an isolated process environment, with a simple shell for interaction. For future gonna work on adding an interface so external applications can be executed inside Runbox, similar to containers.

Github: https://github.com/Sahilb315/runbox

Happy to hear feedback or suggestions.

This article presents a traditional Turkish pasta recipe that combines fresh vegetables, spices, and a unique cooking technique to create a flavorful and satisfying dish. The recipe highlights the versatility of pasta in Turkish cuisine and provides an easy-to-follow guide for home cooks to recreate this authentic cultural dish.

I wrote this tool while debugging a driver because I couldn't find a tool that allowed me to open a file, seek randomly, and read and write.

I thought it might one day be useful to someone too.

The article discusses the Walrus programming language, which is a statically-typed, object-oriented language that aims to provide a powerful and expressive alternative to languages like Python and Rust. Walrus is designed to be efficient, scalable, and easy to use, with a focus on simplicity and developer productivity.

I'm sure folks here have seen pastebins a thousand times. There's no innovation left in this space – and that's kind of the point.

When I wanted to self-host a pastebin, every option I found was too much. Git-based version control, OAuth, elaborate admin panels. I just wanted something I could deploy in under a minute with a CLI that actually works.

So I built pbnj (yes, like the sandwich).

What it is:

- A minimal, beautiful pastebin with syntax highlighting for 100+ languages

- One-click deploy to Cloudflare (free tier gives you ~100,000 pastes)

- CLI-first: pbnj file.py → get a URL, copied to clipboard

- Memorable URLs: crunchy-peanut-butter-sandwich instead of x7f9a2

- Private pastes with optional secret keys

- Web UI for when you're not in a terminal

What it isn't:

- No accounts, no OAuth, no git integration

- No multi-user support (fork it and run your own)

- No expiring pastes, no folders, no comments

- Not trying to replace Gist or be a "platform"

Why not just use Gist? Maybe you want to own your data. Maybe you enjoy self-hosting things. Or maybe you're a little autistic like me and just like having your own stuff.

Live demo: https://pbnj.sh GitHub: https://github.com/bhavnicksm/pbnj CLI: npm install -g @pbnjs/cli

If this scratches an itch for you, I'd appreciate a star on GitHub. Happy to answer any questions!

Hey everyone! I just built a mobile app using Expo (React Native) for a platform that moves $6M/month. It’s a neobank used by 6,500+ nonprofit organizations across the world.

One of my biggest challenges, while juggling being a full-time student, was getting permission from Apple/Google to use advanced native features such as Tap to Pay (for in-person donations) and Push Provisioning (for adding your card to your digital wallet). It was months of back-and-forth emails, test case recordings, and also compliance checks.

Even after securing Apple/Google’s permission, any minor fix required publishing a new build, which was time-consuming. After dealing with this for a while, I adopted the idea of “over the air updates” using Expo’s EAS update service. This allowed me to remotely trigger updates without needing a new app build.

The 250 hours I spent building this app were an INSANE learning experience, but it was also a whole lot of fun. Give the app a try, and I’d love any feedback you have on it!

btw, back in March, we open-sourced this nonprofit neobank on GitHub. https://news.ycombinator.com/item?id=43519802

The article introduces mtxt, an open-source, cross-platform text editor designed for technical and programming-related tasks. It highlights mtxt's features, such as support for multiple programming languages, syntax highlighting, and built-in terminal emulator, making it a versatile tool for developers and writers.

Hey,

My name is Benjamin and as many developers, I was tired to not succeed my technical interviews, for any reasons.

I made SharpSkill in order to change that.

Real Use Case, flashcards & interview simulators.

One goal : Destroy the next technical interviews.

The article recounts the author's reintroduction to computers through the Raspberry Pi, a small, affordable, and versatile single-board computer. It highlights the author's enthusiasm for exploring the capabilities of the Raspberry Pi and its potential for various applications.

I built Fresh to challenge the status quo that terminal editing must require a steep learning curve or endless configuration. My goal was to create a fast, resource-efficient TUI editor with the usability and features of a modern GUI editor (like a command palette, mouse support, and LSP integration).

Core Philosophy:

- Ease-of-Use: Fundamentally non-modal. Prioritizes standard keybindings and a minimal learning curve.

- Efficiency: Uses a lazy-loading piece tree to avoid loading huge files into RAM - reads only what's needed for user interactions. Coded in Rust.

- Extensibility: Uses TypeScript (via Deno) for plugins, making it accessible to a large developer base.

The Performance Challenge:

I focused on resource consumption and speed with large file support as a core feature. I did a quick benchmark loading a 2GB log file with ANSI color codes. Here is the comparison against other popular editors:

  - Fresh:   Load Time: *~600ms*     | Memory: *~36 MB*
  - Neovim:  Load Time: ~6.5 seconds | Memory: ~2 GB
  - Emacs:   Load Time: ~10 seconds  | Memory: ~2 GB
  - VS Code: Load Time: ~20 seconds  | Memory: OOM Killed (~4.3 GB available)

Development process:

I embraced Claude Code and made an effort to get good mileage out of it. I gave it strong specific directions, especially in architecture / code structure / UX-sensitive areas. It required constant supervision and re-alignment, especially in the performance critical areas. Added very extensive tests (compared to my normal standards) to keep it aligned as the code grows. Especially, focused on end-to-end testing where I could easily enforce a specific behavior or user flow.

Fresh is an open-source project (GPL-2) seeking early adopters. You're welcome to send feedback, feature requests, and bug reports.

Website: https://sinelaw.github.io/fresh/

GitHub Repository: https://github.com/sinelaw/fresh

When I bought my home, the big bank I'd been using for years quoted me 7% APR. A local credit union was offering 5.5% for the exact same mortgage.

I was surprised until I learned that mortgages are basically standardized products – the government buys almost all of them (see Bits About Money: https://www.bitsaboutmoney.com/archive/mortgages-are-a-manuf...). So what's the price difference paying for? A recent Bloomberg Odd Lots episode makes the case that it's largely advertising and marketing (https://www.bloomberg.com/news/audio/2025-11-28/odd-lots-thi...). Credit unions are non-profits without big marketing budgets, so they can pass those savings on, but a lot of people don't know about them.

I built this dashboard to make it easier to shop around. I pull public rates from 120+ credit union websites and compares against the weekly FRED national benchmark.

Features:

- Filter by loan type (30Y/15Y/etc.), eligibility (the hardest part tbh), and rate type - Payment calculator with refi mode (CUs can be a bit slower than big lenders, but that makes them great for refi) - Links to each CU's rates page and eligibility requirements - Toggle to show/hide statistical outliers

At the time of writing, the average CU rate is 5.91% vs. 6.23% national average. about $37k difference in total interest on a $500k loan. I actually used seaborn to visualize the rate spread against the four big banks: https://www.reddit.com/r/dataisbeautiful/comments/1pcj9t7/oc...

Stack: Python for the data/backend, Svelte/SvelteKit for the frontend. No signup, no ads, no referral fees.

Happy to answer questions about the methodology or add CUs people suggest.

I've been having fun building out a really simple chess learning app for my daughter (7). It started with just "maze like" puzzles [1] and I've added a few more.

This "radioactive pooping knights" idea came from an Irish primary school chess website [2]. Really simple idea, two knights moving around the board leaving poo behind... Don't be the one forced to step on it.

* best played with sound on.

[1]. https://minichessgames.com/#/movement/knight

[2]. https://ficheall.ie/

*highly subjective, may not be better for you to play with sound at all ;)

p.s. Any "buy me a coffee" goes to my daughter. Annoyingly they only pay out once you get above $10 USD and I think it's currently sitting at 9.85 or something!

I built an AI version of Paul Graham, fully powered by the Nia API.

* Nia gives coding agents accurate context by indexing entire codebases, documentation, and packages. It fixes hallucinations by letting agents retrieve real source information instead of guessing. Developers ship faster because AI can read and understand their actual project. This is a different use case of Nia but apparently it also works.

You can chat with it and ask any question because it has access to Nia’s knowledge base, which indexed all of his personal essays. The agent is able to call multiple tools that directly use Nia’s API:

• NiaWebSearch - searches the web • searchEssays - semantic search over all essays • browseEssays - shows the full tree of essays • listDirectory - lists essays in a path • readEssay - reads full essay content • grepEssays - regex pattern search • getSourceContent - retrieves full source by identifier

Models: anthropic/claude-sonnet-4.5 moonshotai/kimi-k2-thinking xai/grok-4-fast-reasoning alibaba/qwen3-vl-thinking

It’s fully free and open source.

Try it: https://www.paulgraham-nia.com/ Code: https://github.com/nozomio-labs/paulgraham-ai

AI coding assistants are productive but sloppy. They produce code that looks right but:

- Imports packages that don't exist - Uses placeholder functions that do nothing - Leaks patterns from JavaScript, Java, Ruby into Python - Leaves behind dead code and duplicates - Uses mutable default arguments

I built sloppylint to catch these "AI slop" patterns before they hit production.

     pip install sloppylint
     sloppylint .

This isn't a replacement for traditional linters - it catches the specific mistakes AI makes that humans wouldn't.

https://github.com/rsionnach/sloppylint

It all started as an experiment to see if I could build a game making heavy use of Deno and its SQLite driver. After sharing an early build in the „What are you working on?“ thread here, I got the encouragement I needed to polish it and make a version 1.0 for Steam.

So here it is, Microlandia, a SimCity Classic-inspired game with parameters from real-life datasets, statistics and research. It also introduces aspects that are conveniently hidden in other games (like homelessness), and my plan is to continue updating, expanding and perfecting the models for an indefinite amount of time.

Hi HN,

I’m an ex-Amazon engineer. I built Seychl because I was tired of waiting 3 seconds for my notes to load in cloud-based apps.

Seychl is a local-first knowledge base designed for speed. UI interactions are always instant (<16ms).

Features for power users:

- Full keyboard control (never touch the mouse)

- Vim mode built-in

- Markdown storage (you own your data)

- Instant search across 10k+ notes

- Persistent Tmux-like sessions, windows and panes

It’s basically "Linear for knowledge management" – focusing on ergonomics and speed over bloated features.

You can download the binary here (currently MacOS only): https://github.com/Seychl/seychl-release/releases/download/0...

I built a RAG application that retrieves relevant Bhagavad Gita verses for ethical dilemmas and generates structured guidance.

The problem: The Gita has 701 verses. Finding applicable wisdom for a specific situation requires either deep familiarity or hours of reading.

How it works: 1. User describes their ethical dilemma 2. Query is embedded using sentence-transformers 3. ChromaDB retrieves top-k semantically similar verses 4. LLM generates structured output: 3 options with tradeoffs, implementation steps, verse citations

Tech stack: - Backend: FastAPI, PostgreSQL, Redis - Vector DB: ChromaDB with all-MiniLM-L6-v2 embeddings - LLM: Ollama (qwen2.5:3b) primary, Anthropic Claude fallback - Frontend: React + TypeScript + Tailwind

Key design decisions: - RAG to prevent hallucination — every recommendation cites actual verses - Confidence scoring flags low-quality outputs for review - Structured JSON output for consistent UX - Local LLM option for privacy and zero API costs

What I learned: - LLM JSON extraction is harder than expected. Built a three-layer fallback (direct parse → markdown block extraction → raw_decode scanning) - Semantic search on religious texts works surprisingly well for ethical queries - Smaller models (3B params) work fine when constrained by good prompts and retrieved context

GitHub: https://github.com/geetanjaliapp/geetanjali

Happy to discuss the RAG architecture or take feedback.

Got tired of wiring up vector stores, embedding models, and chunking logic every time I needed RAG. So I built piragi.

  from piragi import Ragi

  kb = Ragi(\["./docs", "./code/\*\*/\*.py", "https://api.example.com/docs"\])

  answer = kb.ask("How do I deploy this?")

What it does:

  - All formats - PDF, Word, Excel, Markdown, code, URLs, images, audio

  - Auto-updates - watches sources, refreshes in background, zero query latency

  - Citations - every answer includes sources

  - Advanced retrieval - HyDE, hybrid search (BM25 + vector), cross-encoder reranking

  - Smart chunking - semantic, contextual, hierarchical strategies

  - OpenAI compatible - swap in GPT/Claude whenever you want

  # Filter by metadata
  answer = kb.filter(file_type="pdf").ask("What's in the contracts?")

  #Enable advanced retrieval

    kb = Ragi("./docs", config={
     "retrieval": {
        "use_hyde": True,
        "use_hybrid_search": True,
        "use_cross_encoder": True
     }
   })


  # Use OpenAI instead  
  kb = Ragi("./docs", config={"llm": {"model": "gpt-4o-mini", "api_key": "sk-..."}})

  pip install piragi
  PyPI: https://pypi.org/project/piragi/

Hi HN,

I built a tiny tool because I couldn’t find a clean, distraction-free monthly planner that:

1. shows a clean monthly task view 2. doesn’t require an account 3. doesn’t sync or store anything online 4. works offline 5. is printable 6. and keeps a minimal, distraction-free aesthetic

So I made https://printcalendar.top/ — a minimal monthly task planner.

It’s intentionally simple. No logins, no integrations, no dashboards. Just a small tool for people who want structure without clutter.

No signup required—just upload or record a video to verify its truthfulness. You can test it on anyone: internet clips, your significant other, or even yourself.

I'm aware there are tons of scammy 'lie detector' apps out there, but I built this using SOTA multimodal models in hopes of creating a genuine breakthrough in the space.

It analyzes micro-expressions, voice patterns, and context. In my own testing (over 50 trials), it reached about 85% accuracy, which honestly felt a bit scary.

It’s also fun to test on famous YouTube clips (like Obama talking about UFOs). I’d love to hear what you think and will be improving Watsn.ai every day based on your feedback!