
OneUtil
A Roof for all utilities.
What it does
22 developer tools in one keyboard-first app — JSON editor, PDF toolkit, JWT decoder, regex tester, hash, QR, cron, color, diagrams, converters. Everything runs 100% in your browser: no backend, no accounts, no uploads. Your data never leaves the tab, and the whole suite keeps working offline (only live currency rates need a network, and it says so). Depth over count: JSON Schema validation, realdocx + text PDF export, ReDoS-safe regex, diagrams that sync text and canvas both ways. Free.
Does the same job
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- RFRawkit – Free, no-ads developer tools that run in the browserFeb 2026 · rawkit.dev · ▲8
Hey HN, I built rawkit.dev, a collection of browser-based developer utilities. No ads, no signups, no tracking. Everything processes client-side — your data never touches a server. The tools: - JSONForge: JSON editor with tree/graph views, diff, transform, JQ-style queries, format conversion - SQLSandbox: SQLite via WASM — import CSVs, write SQL, join across files - Regexplorer: Regex builder with live matching, plain English mode,nmulti-language export - SiftLog: Log file viewer with auto-detection, severity filtering, regex search, timeline - Tabulate: CSV/TSV viewer with…
Everyday Dev Tools12d ago · toolsfordev.tools · ▲1free developer tools that work offline, in your browser
PureDevUtils13d ago · puredevutils.com · ▲1Free browser-based dev tools that never upload your data.

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Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com

OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 2d ago · opentrailpaper.com

Launched alongside, August 2026
the whole month →- TL
Life & fun · 10d ago · louisabraham.github.io


- SA
Hello HN! I found that picking out plausible but diverse skin tones for my digital art and game development projects was kind of difficult, and I got curious about if there was a way to define a color space that made it easy. I've built a color picker and procedural generation algorithm based on the space as well as a bunch of other fun js features and demos throughout the page that use the equations. If you find it interesting, I have lots of explanations of how I built it and what properties the space has. The methodology might be a bit shaky, but hopefully the result is as helpful for…
Life & fun · Aug 2026 · toneyalexander.github.io


I trained a 125M-parameter transformer to autocomplete piano performances in real time (~108 notes/sec on an iPhone 15). The idea is basically GitHub Copilot or Tabnine, except instead of prompting it with code, you prompt it by playing a few notes on a MIDI piano. The model then continues what you played, entirely on-device. The app is free if anyone wants to try it. Happy to answer questions about the model, training, Core ML, or the many things that didn't work.
AI · 17d ago · simedw.com