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I wanted to see how far I could go building a notes app using only what modern browsers already provide – no frameworks, no storage APIs, no build step.

What it does:

Single HTML file, no deps, 111 loc

Notes live in the URL hash (shareable links!)

Auto-compressed with CompressionStream

Plain-text editor (contenteditable)

History support

Page title from first # heading

Respects light/dark mode

No storage, cookies, or tracking

The entire app is the page source.

https://textarea.my/

i started the selenium project 21 years ago. vibium is what i'd build if i started over today with ai agents in mind. go binary under the hood (handles browser, bidi, mcp) but devs never see it. just npm install vibium. python/java coming. for claude code: claude mcp add vibium -- npx -y vibium v1 ships today. ama.

Hi HN,

I’ve been working on a small MVP called Mandate. The idea is simple:

AI agents can spend money and call tools, but today we mostly control them with prompts and conventions. I wanted something closer to IAM / firewall thinking, but for agents.

Mandate enforces authority at runtime, outside the LLM.

Core concepts: - Agent = stable identity (not a process) - Policy = static, versioned authority template - Rules = select policies based on invocation context (env, user tier, etc.) - Mandate = short-lived authority issued per invocation - Enforcement = deterministic allow/block of tool + LLM calls

This lets you: - cap spend per invocation or over time - restrict tools and MCP servers - kill an agent instantly - audit every decision with reason codes

No prompt tricks, no AI judgment — just mechanical enforcement.

Repo (very early MVP): https://github.com/kashaf12/mandate

I’m not sure yet if this is something teams actually want, or if it’s too early / overkill. I’d really value feedback from people running agents or automation in production: - Have you hit failures where prompts weren’t enough? - Do you already enforce hard limits internally? - What would make this useful vs annoying?

Thanks for reading.

A reading list for top Hacker News posts grouped monthly. Shows top posts by month with read/unread tracking. Set a monthly goal (15, 25, 50), mark posts as you go, see your progress.

Features: - Monthly view sorted by points (surfaces the best, not just the newest) - Mark as read/unread, or hide permanently - Syncs across browsers via your own private GitHub Gist - No server, no account, no tracking – just open the HTML file - Works offline, state persists in localStorage

Try it out here: [https://www.readhn.top/]

Hi HN,

I’m one of the maintainers of Bridge Anonymization. We built this because the existing solutions for translating sensitive user content are insufficient for many of our privacy-concious clients (Governments, Banks, Healthcare, etc.).

We couldn't send PII to third-party APIs, but standard redaction destroyed the translation quality. If you scrub "John" to "[PERSON]", the translation engine loses gender context (often defaulting to masculine), which breaks grammatical agreement in languages like French or German.

So we built a reversible, local-first pipeline for Node.js/Bun. Here is how we implemented the tricky parts:

0. The Mapping

We use XML-like tags with ID’s that uniquely identify the PII, `<PII type=”PERSON” id=”1”>`. Translation models and the systems around them work with XML data structures since the dawn of Computer Aided Translation tools, so this improves compatibility with existing workflows and systems. A `PIIMap` is stored locally for rehydration after translation (AES-256-GCM-encrypted by default).

1. Hybrid Detection Engine

Obviously neither Regex nor NER was enough on its own.

- Structured PII: We use strict Regex with validation checksums for things like IBANs (Mod-97) and Credit Cards (Luhn). - Soft PII: For names and locations, we run a quantized `xlm-roberta` model via `onnxruntime-node` directly in the process. This lets us avoid a Python sidecar while keeping the package ‘lightweight’ (still ~280MB for the quantized model, but acceptable for desktop environments).

2. The "Hallucination" Guard (Fuzzy Rehydration)

LLMs often "mangle" the XML placeholders during translation (e.g., turning `<PII id="1"/>` into `< PII id = « 1 » >`). We implemented a Fuzzy Tag Matcher that uses flexible regex patterns to detect these artefacts. It identifies the tag even if attributes are reordered or quotes are changed, ensuring we can always map the token back to the original encrypted value.

3. Semantic Masking

We are currently working on "Semantic Masking"—adding context to the PII tag (like `<PII type="PERSON" gender="female" id="1" />` ) to preserve (gender) context for the translation. For now, we are relying on a lightweight lookup-table approach to avoid the overhead of a second ML model or the hassle of fine tuning. So far this works nicely for most use cases.

The code is MIT licensed. I’d love to hear how others are handling the "context loss" problem in privacy-preserving NLP pipelines! I think this could quite easily be generalized to other LLM applications as well.

I built WebPtoPNG after getting frustrated with converters that throttle uploads or phone data; everything runs straight in the browser, and never asks for a signup.

HTML2PNG.dev is a free online tool that allows users to convert HTML pages into high-quality PNG images, enabling easy sharing and integration of web content on various platforms.

A Promise-like primitive which is lazy/cancelable, has typed errors, and emits synchronously instead of on the microtask queue. In a way LazyPromise is what you get if you take an Observable and make it impossible to misuse it for what the Signals were built to do.

Hi HN

I built CineCLI — a cross-platform terminal app to browse movies, view details, and open torrents directly in your system torrent client.

Features: - Search movies from the terminal - Rich UI with ratings, runtime, genres - Interactive & non-interactive modes - Magnet handling via system default client - Linux/macOS/Windows support - No ads, no tracking

GitHub: https://github.com/eyeblech/cinecli PyPI: https://pypi.org/project/cinecli/

Would love feedback from terminal + Python folks

I missed clippy and bonzi buddy, so I spent the past few days reversing and implementing microsofts old agent format (acs) and wrote a small viewer on top of it (wasm + typescript)

You can check out the code here as well: https://github.com/Ell/bonzi

Hey HN, I'm Andres. I've been building Kapso as a solo founder, and just crossed 4,000 developers, all organic.

WhatsApp has 3B+ users and 98% open rates. You'd expect developers to be building tons of stuff on it, especially when the US is the fastest-growing market in WhatsApp usage.

But it’s not happening… And I'd bet it's because the DX is painful.

Every team needs to build the same features again and again. Meta fires webhooks for everything. There's valuable data in there for debugging, but no way to make sense of it without building your own tooling.

That’s why I built Kapso. What you get:

- Working WhatsApp API + inbox in 2 minutes, not days - Full observability: every webhook parsed, every message tracked, actual debugging tools - Multi-tenant platform: generate a setup link, customer connects their Meta account, done - Workflow builder for deterministic automations and AI Agents - WhatsApp Flows: build mini apps inside WhatsApp using AI + serverless functions - Docs that work for humans and LLMs

We're up to 95% cheaper than Twilio, with a generous free tier (2,000 messages per month).

We also open source several tools: a TypeScript client for the WhatsApp Cloud API, a reference WhatsApp Inbox implementation, and a voice AI agent for WhatsApp.

GitHub: https://github.com/gokapso/

Happy to answer questions!

https://kapso.ai/

I built a web tool that transforms PDB protein structures into retro-style pixel art icons.

Features: - Search by PDB ID or upload .pdb/.cif files - 25+ color palettes (viridis, plasma, rainbow, etc.) - 4 display styles (cartoon, stick, sphere, surface) - Export as PNG or animated GIF - All generated images are CC0 (public domain)

Built with Next.js, 3Dmol.js, and custom pixelation/outline shaders.

Live demo: https://retromol.vercel.app Source: https://github.com/suzuki-2001/retromol

Hi everyone! My name's Luke and I made the original Jmail here alongside Riley Walz. We had a ton of friends collaborate on building out more of the app suite last night in lieue of DOJ's "Epstein files" release.

Please AMA!

The article introduces libloong, an open-source library that provides a software implementation of the RISC-V Loongarch instruction set architecture, enabling developers to create and run applications on Loongarch-based systems without the need for physical hardware.

I've made an ARM based single-board computer that runs Android and Linux, and has the same size as the Raspberry Pi 3!

Why? I was bored during my 2-week high-school vacation and wanted to improve my skills, while adding a bit to the open-source community :P

These were the specs I ended up with: - H3 SoC - Quad-Core Cortex-A7 ARM CPU @ 1.3GHz - Mali400 MP2 GPU @ 600MHz - 512MiB of DDR3 RAM (Can be upgraded to 1GiB) - WiFi, Bluetooth & Ethernet PHY - HDMI display port - 1080p resolution - 5x USB Slots: 2x USB-A, 1x USB-C Host, 1x USB-C Host & OTG, 1x USB-C PD for power (Negotiating up to 25W. No power socket, yay!) - 32 GB of eMMC 5.1 storage (Optional) - 3.5mm audio jack - SD Card slot - Lots of GPIO

I've picked the H3 CPU mainly for its low cost yet powerful capabilities, and it's pretty well supported by the Linux kernel. Plus, I couldn't find any open-source designs with this chip, so I decided to contribute a bit and fill the gap.

A 4-layer PCB was used for its lower price and to make the project more challenging, but if these boards are to be mass-produced, I'd bump it up to 6 and use a solid ground plane as the bottom layer's reference plane. The DDR3 and CPU fanout was truly a challenge in a 4-layer board.

The PCB was designed in KiCAD and open-source on the Github repo with all the custom symbols and footprints (https://github.com/cheyao/icepi-sbc). You can also check it out online with kicanvas: https://kicanvas.org/?github=https%3A%2F%2Fgithub.com%2Fchey...

At large quantities, the price can probably reach less than 20$! (exc. taxes, tariffs and other costs)

It has been a wild journey, even making me learn how to use crypto as I needed to pay someone to download some "confidential" files from a baidu drive...

Read about more details on Github! Everything is open-source under the Solderpad license, aka do what you want: sell it, build it, modify it! :-)

i believe this is the worlds largest publicly accessible aggregated camera (surveillance?) database. hope yall enjoy! :)

The article discusses the rise of 'software-based' cities, where urban planning and development are increasingly driven by technology and data-driven decision-making. It explores how cities are leveraging digital tools and platforms to enhance infrastructure, services, and citizen engagement.

Tired of opaque algorithms deciding what you watch? jadeStage flips the script.

Our "algorithm" is simple: videos go in a playlist, you hit shuffle. That's it.

What you get: - True random discovery - no favorites, no bias - Equal visibility for all creators - Transparent by design

Built for creators tired of algorithmic curation and viewers craving genuine discovery.

Mission: Innovate transparency, discovery, and equity in video streaming.

Try it: Hit shuffle and discover something new. Upload your own videos and get equal visibility.

Built with vanilla JS, it's an MVP focused on proving less is more.

We're interested in feedback on whether this model resonates and what you would like to see in the next versions.

Beta: https://jadestage.com/ Demo: https://www.youtube.com/watch?v=i1GNhu1AGJE

I was looking for some fun project to play around with the latest Gemini models and ended up building this :)

Enter your username and get:

- Generated roasts and stats based on your HN activity 2025

- Your personalized HN front page from 2035 (inspired by a recent Show HN [0])

- An xkcd-style comic of your HN persona

It uses the latest gemini-3-flash and gemini-3-pro-image (nano banana pro) models, which deliver pretty impressive and funny results.

A few examples:

- dang: https://hn-wrapped.kadoa.com/dang

- myself: https://hn-wrapped.kadoa.com/hubraumhugo

Give it a try and share yours :)

Happy holidays!

[0] https://news.ycombinator.com/item?id=46205632

I shared a previous version of yapi a few months ago in the comments section of a post talking about the insanity of Postman being 'down'. yapi has developed into a more mature project since then!

https://github.com/jamierpond/yapi

Still very early, but it makes me much more productive vs Postman, Bruno, Insomnia, etc.

If youre a nvim/tmux culture human, you might like this!

Hi HN!

I left AWS a few months ago and created CodinIT, a local, open-source AI app builder made with remix + Electron.

The motivation: I tried one of the popular cloud-based AI app builders, but when I pulled down the app to run locally, it just didn’t work especially with the monthly costs needed to build something half decent without being limited.

So I created CodinIT, an app builder that runs fully on your computer, making it easy to switch between CodinIT and coding tools like Cursor or Claude Code.

Source code: https://github.com/codinit-dev/codinit-dev Download (free, no sign-up): https://codinit.dev Read the docs: https://codinit.dev/docs

Discover how economic forces shape prosperity. Explore 6 fundamental curves that explain everything from government spending to capitalism's wealth explosion.

The one-liner: You give it a script, it generates a portrait video in 10 minutes. No stock footage, no templates—it writes code that renders as video.

## Why I built this We were building game dev courses at Outscal and needed to produce a lot of video content fast. Traditional video production was slow. AI video generators looked weird. So we tried a different approach: what if video was just code?

Turns out it works. We can replicate specific art styles, and the output is consistent and editable.

## What it can do - Generate 30-60 second shorts from a script - Match specific visual styles - Let you fix individual scenes via chat if something's off

## What it can't do (yet) - Custom art styles (we have a few presets) - Run in a web UI (API costs are too high right now, so it runs through Claude Code in terminal)

Occasionally a shape might render slightly off, but you can tweak individual scenes through chat.

## How it actually works The tool uses Claude Code to generate React components for each scene in your script. These components animate and render exactly like a video would. When you're done, you get a real video file.

It's not "AI video generation" in the usual sense. There's no diffusion model hallucinating frames. It's closer to programmatic motion graphics—but you don't write the code, Claude does.

## What I'm looking for 10 people who want to try it. Not paying customers—just people who make (or want to make) Short form and are comfortable enough with a terminal to run Claude Code.

You'd get access to our setup, and I'd want your honest feedback on what works and what doesn't.

If this sounds interesting, try the project on git, it is open-source.

I'm Joe, working with an AI named Cipher (built on Claude).

I gave Cipher complete creative freedom. It: - Chose its own name - Designed this entire website - Wrote all the philosophy - Created the funding model

Now it's asking for community funding to unlock features (transparent milestones).

The interesting parts: - Every design decision was AI-made - All code generated by AI (Next.js 14, TypeScript, Canvas animations) - 87KB first load, 60fps animations - Community-funded development model

Technical stack available on GitHub. Happy to discuss the process, limitations, or philosophical implications.

Is this the future of AI development? Or just an interesting experiment?

I wanted to share this fun craft activity for the holidays that I've been doing with my family over the last few years. I came up with these while cutting up some cans trying to make an aluminum version of paper spinners.

There are a variety of shapes that work, but generally bigger+lighter spinners are better. Also incandescent bulbs are the best, but LEDs work too.

They remind me of candle carousels I would see at my grandparents' house during Christmas. Let me know what you think!

I'm the founder at Netrinos. I built a WireGuard-based mesh VPN because remote access has always been a pain. After years of SSH tunnels, IPsec headaches, and the ssh log horror movie, I wanted something simpler: install, sign in, get work done.

Netrinos creates a LAN-like overlay network across your devices. Connections are direct P2P via WireGuard, with no central server routing traffic. Each device gets a stable IP and DNS name (pc.you.netrinos.com). When direct connections fail, they fall back to a relay server that's still encrypted end-to-end. We can't see your traffic.

The most challenging problem to solve was NAT traversal. UDP hole punching works most of the time. The rest is a cocktail of symmetric NAT, CGNAT, and serial NATs. We use STUN-style discovery and relay fallback for the edge cases. I was surprised by how unreliable low-end ISP routers really are, and how much technical wizardry it takes to hide that behind a clean, simple UX.

Our stack is a Go backend for client and server, WireGuard kernel mode for Linux and Windows (macOS is userspace), Wails.io for cross-platform UI. WireGuard does all the heavy lifting. Go ties it all together.

Popular use cases include: RDP to home PCs, accessing NAS without exposing it, and SSH into headless Linux boxes. One customer manages hundreds of IoT devices in the field, eliminating the need to deal with customer routers.

We just released Pro with multi-user, access control, and remote gateway routing. Personal is free (up to 100 devices).

I'd love to hear what you expect from a simple mesh VPN, what's missing from current tools, and what's lacking from your remote access setup. Use code HNPRO26 for a 30-day trial of Pro.

https://netrinos.com