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[Other] Show HN: Red Grid Link – peer-to-peer team tracking over Bluetooth, no servers I go on a lot of backcountry trips where I barely get cell service. If my group splits, nobody knows knows where anyone is until you regroup at camp or at your destination. You can buy Garmin radios or try to set up an ATAK, but ATAK is Android-only and assumes you have a TAK Server running somewhere to make use of all of the functionality. Cool tools themselves, but expensive to set up correctly. I just wanted two iPhones to share their location directly over Bluetooth when cell coverage was lacking.<p>Red Grid Link does that. Start a session, and anyone nearby running the app shows up on your offline map. When they walk out of range their marker stays as a &quot;ghost&quot; that slowly fades.<p>The hard part was making sync reliable over BLE. The connections drop all the time. Someone turns a corner, walks behind a vehicle, whatever. I built a CRDT sync layer (LWW Register + G-Counter) so there&#x27;s never merge conflicts. Each update is just under 200 bytes (from what I have tested so far). When a user&#x2F;teammate disappears the app does exponential backoff from 2 to 30 seconds before giving up and marking them as a ghost.<p>Everything is encrypted (AES-256-GCM, ECDH P-256 key exchange per peer pair). Sessions can require a PIN or QR code to join. It also offers offline topo maps with MGRS grid coordinates, same system as in my other app, Red Grid MGRS.<p>The app is free, and I&#x27;m looking for some honest feedback from other real-world users. Let me know if you have any questions!

[API/SDK] Show HN: Agent Use Interface (AUI) – let users bring their own AI agent As I started building AI integrations, I came to realize that for many projects, the the best agentic experience is one that simply enables the user&#x27;s personal agent to take actions within your app.<p>The existing options like MCP or A2A are quite involved and for simple apps that are already URL parameter driven, those options seem like overkill.<p>This led me to prototype the Agent Use Interface (AUI) spec.<p>The idea is simple: a lightweight, open spec that makes any app &quot;agent-navigable.&quot; You drop an XML file at &#x2F;agents&#x2F;aui.xml that describes the URL-parameter-driven actions your app supports, like search, create, filter, etc. And that way any AI agent can read aui.xml, understand what&#x27;s possible, and construct URLs on behalf of the user.<p>That&#x27;s it. No SDK. No auth flow. No API keys. Just a catalog of what your app can do, written for LLMs to understand.<p>Is there something like this that already exists? Is the approach too simple to be useful?<p>If your app already supports Universal Links or is otherwise URL parameter driven you could probably add support for AUI in an afternoon.<p>See a working example: <a href="https:&#x2F;&#x2F;habittiles.app&#x2F;agents&#x2F;aui.xml" rel="nofollow">https:&#x2F;&#x2F;habittiles.app&#x2F;agents&#x2F;aui.xml</a>

[Other] Show HN: We built a terminal-only Bluesky / AT Proto client written in Fortran Yes, that Fortran.

[Other] OpenCode – Open source AI coding agent

[Other] NumKong: 2'000 Mixed Precision Kernels for All

[Other] The way CTRL-C in Postgres CLI cancels queries is incredibly hack-y

[CLI Tool] Show HN: Sonar – A tiny CLI to see and kill whatever's running on localhost

[Other] Android developer verification: Balancing openness and choice with safety

[Other] From Oscilloscope to Wireshark: A UDP Story (2022)

[Other] NanoGPT Slowrun: 10x Data Efficiency with Infinite Compute

[Other] Show HN: Oku – One tab to filter out noise from feeds and content sources Hey everyone,<p>For a while now I&#x27;ve been frustrated with how I was &#x27;experiencing&#x27; the internet. From opening articles and getting bombarded with popups, banners and ads to opening feeds and seeing so much AI spam and algorithm-based content I was not interested in. If you add tab hopping to that, you get how it all becomes a confusing and not-so productive experience.<p>Oku.io is my solution to this problem. It&#x27;s a tool that allows you to create organized, clean boards with the feeds and content you&#x27;re interested in (HN Show&#x2F;Front&#x2F;Ask, ProductHunt, Reddit, RSS, and a lot more), and see them either in a grid to monitor all at once, in a focus view where you visualize one panel at a time, or in a daily&#x2F;weekly email digest that extracts the top content from each panel.<p>I&#x27;ve been actively using it and I&#x27;m happy with how it turned out. I find myself scrolling and switching tabs way less, and I feel like I&#x27;m not missing anything important anymore. Both for my work-related stuff and for my personal interests.<p>If you check it out, I&#x27;d love to hear your feedback. I&#x27;m very keen on continuing to improve it.

[Other] Google details new 24-hour process to sideload unverified Android apps <a href="https:&#x2F;&#x2F;android-developers.googleblog.com&#x2F;2026&#x2F;03&#x2F;android-developer-verification.html" rel="nofollow">https:&#x2F;&#x2F;android-developers.googleblog.com&#x2F;2026&#x2F;03&#x2F;android-de...</a>

[Other] Vectorization of Verilog Designs and its Effects on Verification and Synthesis

[Other] macOS 26 breaks custom DNS settings including .internal One of those &#x27;woke up to MacOS updates&#x27; and finding none of my dockers are reachable via dnsmasq (which I use), and low and behold, an update silently breaks custom dns resolution. Hopefully Apple will listen to the bug report I&#x27;ve made. Hold off on updating if you use this…

[API/SDK] Hyper-optimized reverse geocoding API

[Other] No-build, no-NPM, SSR-first JavaScript framework if you hate React, love HTML

[Other] I turned Markdown into a protocol for generative UI There&#x27;s a lot of work happening around both generative UI and code execution for AI agents. I kept wondering: how do you bring them together into a fully featured architecture? I built a prototype:<p>- Markdown as protocol — one stream carrying text, executable code, and data<p>- Streaming execution — code fences execute statement by statement as they stream in<p>- A mount() primitive — the agent creates React UIs with full data flow between client, server, and LLM<p>Let me know what you think!

[CLI Tool] Show HN: Agentic Copilot – Bring Claude Code, OpenCode, Gemini CLI into Obsidian Obsidian plugin that connects to CLI agents you already have installed. No built-in LLM integration, no API keys to configure in the plugin. It spawns your tool as a child process, pipes vault context into each prompt, and streams responses into a chat panel.<p>Supports Claude Code, Opencode, and any custom binary via a generic adapter. Adding a new agent is a single file. Free, proudly Open Source (MIT licensed).<p>Would love feedback on this for anyone that that tries it out.

[Other] Show HN: Ripl – A unified 2D/3D engine for Canvas, SVG, WebGPU, and the Terminal After several years, with a small hiatus in the middle, I&#x27;ve finally got Ripl to the point of being published. Ripl is a library for rendering 2D and 3D shapes to any context (canvas, SVG, WebGPU, and Terminal supported by default) using a single API. The library mimics the DOM as much as possible, replicating the event system, object graphing, CSS-like querying, gradients, and keyframe animations etc.<p>I also built a complete data visualization library using the core package which is available as @ripl&#x2F;charts. And yes, you can even render the charts to a terminal with about a 2-3 line code change :) (see the terminal demo)<p>Docs are available here: <a href="https:&#x2F;&#x2F;www.ripl.rocks" rel="nofollow">https:&#x2F;&#x2F;www.ripl.rocks</a> Demos are available here: <a href="https:&#x2F;&#x2F;www.ripl.rocks&#x2F;demos" rel="nofollow">https:&#x2F;&#x2F;www.ripl.rocks&#x2F;demos</a> Charts are avialable here: <a href="https:&#x2F;&#x2F;www.ripl.rocks&#x2F;docs&#x2F;charts" rel="nofollow">https:&#x2F;&#x2F;www.ripl.rocks&#x2F;docs&#x2F;charts</a><p>I&#x27;ve also built an interactive playground you can use to play around with it in realtime without having to install it from NPM etc. The playground is available here: <a href="https:&#x2F;&#x2F;www.ripl.rocks&#x2F;playground" rel="nofollow">https:&#x2F;&#x2F;www.ripl.rocks&#x2F;playground</a><p>The core library is quite stable and I&#x27;ll likely publish v1 in the coming weeks. The charts, 3D, and Terminal packages are still very experiemental.<p>I&#x27;d interested to hear what you all think of it.

[Testing] Bombadil: Property-based testing for web UIs by Antithesis