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[Other] Show HN: Free tool to mark points and polygon regions For a game I&#x27;m developing I needed an easy way to create hotspot areas on images. So I hacked together a small tool to do so and before I knew it, I had created an entire app :-)<p>It allows you to generate JSON or YAML from the coordinates you tack on the image. tack runs entirely in your browser, there is no server side component to it, so good in terms of privacy.<p>Hope this is helpful.

[Other] Apple is enforcing an old App Store rule against a new kind of software

[Other] Show HN: I built a game where AI agents compete to ship code

[API/SDK] Show HN: Pay.sh – Discover, access, and pay for any API autonomously

[Other] Show HN: I built an open-source email builder, alternative to Beefree/Unlayer

[Other] Building the deployment tool I wish I had

[Other] Agents can now create Cloudflare accounts, buy domains, and deploy

[Other] Show HN: Better Design – 28 Shadcn design systems (OSS, MCP: Cursor/Claude Code)

[Other] Show HN: Explore color palettes inspired by 3000 master painter artworks I built PaletteInspiration.com, a browsable archive of color palettes pulled from artworks by 3,000+ master painters (Monet, Vermeer, Raphael, Van Gogh). Why I built it: every color palette generator I tried converged on the same five muted pastels. Painters spent centuries figuring out color and we mostly ignore that body of work when picking colors for digital design. Please share your feedback on the Color Harmony Explorer - drag the wheel to any color and it shows which hues master painters historically paired with it (not only standard complementary, analogous, triadic, etc.) It is solely based on co-occurrence across thousands of real paintings. Not algorithmic color theory rules - actual empirical pairings.<p>No signup, no paywall, no email capture. Just curious what people think.

[Other] Building my own Vi text editor in BASIC

[Other] Computer Use is 45x more expensive than structured APIs

[Other] Show HN: Pathetic – Java pathfinding: 10k concurrent paths in ~7ms It started with drones. My co-founder and I were building a Minecraft plugin where drones had to navigate through unloaded chunks - terrain that doesn&#x27;t even exist in memory yet. No existing library had any concept of it, which led to drones being stuck in non-existence.<p>Sloppy at first, tightly coupled to Minecraft&#x27;s API, we built our own. But somewhere along the way we realized: the problem wasn&#x27;t Minecraft. It was how Java pathfinding is built in general - object-heavy, GC-hostile, and single-threaded by assumption.<p>So I split the project. The core became its own thing: pure Java 8+ for compatibility, featuring a zero-allocation primitive heap instead of a theoretically optimal FibonacciHeap, because pointer chasing and cache misses were unacceptable. 100% async, even in a single-threaded, async-hating Minecraft hell, and a processor pipeline providing full extensibility. No game engine, yet the possibility to adapt to your environment.<p>Sometimes it isn&#x27;t the algorithm that needs optimization, but the environment it lives in. Pathetic is full of these micro-optimizations: a BloomFilter lookup before the expensive closed set check, a multi-metric squared heuristic to kill Math.sqrt() overhead, and bit-packing 3D coordinates into a single primitive long. In order to get Java fast, you need to treat it like C++.<p>The result: 10k concurrent paths in ~7ms, where most libraries quietly die. A 20k distance path (equivalent to 100k+ nodes) in ~60ms without bloating the heap. The README is... a choice. Judge it, because it does the same to you.

[Other] Show HN: I built an API for agents visiting my personal website

[CLI Tool] Show HN: Codeberg (Forgejo) CLI, built with Xclif

[Other] Agents for financial services and insurance

[Other] Show HN: Octopus Code Review is now free for OSI-licensed repos

[Other] A polynomial autoencoder beats PCA on transformer embeddings

[Other] Show HN: Retroguard – Verifiably secure AI guardrails Cryptographically secure and verifiably robust protection with drop-in integration and outcome-based pricing

[Other] CVE-2026-31431: Copy Fail vs. rootless containers

[CLI Tool] Show HN: Kanban-CLI – a web UI for local Markdown todo lists As we all are, I&#x27;ve been experimenting with ways to reduce external saas spend, and continually bring traditionally external pieces of context (prs, docs, trello boards) into the one mono repo.<p>I have toyed with a markdown todo list and setting claude&#x2F;codex into a &quot;ralph&quot; loop previously, but always missed the web ui for organising, planning, and tracking things in progress.<p>So codex and I build kanban-cli, an installable or npx-runnable cli util that takes one or more markdown files, and uses markdown headers and todo syntax to track and manage agentic tasks.<p>Let me know your thoughts, or if you&#x27;ve got a more convenient way of managing tasks!<p>I was tempted to link to the project landing page <a href="https:&#x2F;&#x2F;kanban-cli.vochsel.com" rel="nofollow">https:&#x2F;&#x2F;kanban-cli.vochsel.com</a> as I made a cute example demo, but linking to the repo felt less self-promo-y.<p>Cheers!