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[Other] Optimizing a 6502 image decoder, from 70 minutes to 1 minute

[Other] Show HN: Free developer-first OneNote alternative Hey Everyone, been working on a note-taking app called janta (Just Another Note Taking App) the past few months.<p>You can try it out at app.janta.dev (you will be redirected to app.janta.dev&#x2F;canvas&#x2F;temporary, which is the locally-stored whiteboard you can access)<p>I felt limited with OneNote, Excalidraw, and other infinite-canvas style apps, so I built an alternative. You have access to code-editors, Desmos graphs, and rich text editors (SlateJS). This is because the canvas is designed in a way that allows web components to exist on the same layer as pen-strokes, so you can annotate code, circle points-of-inflection, and programmatically generate graphs using matplotlib.pyplot!<p>This is a beta release, and feedback would be awesome!

[Other] Coding a new BASIC interpreter in 2025 to replace a slow one

[Other] Show HN: Built an MCP server using Cloudflare's Code Mode pattern Read this article by Cloudflare this morning <a href="https:&#x2F;&#x2F;blog.cloudflare.com&#x2F;code-mode&#x2F;" rel="nofollow">https:&#x2F;&#x2F;blog.cloudflare.com&#x2F;code-mode&#x2F;</a> the main argument being that LLMs are much better at writing typescript code than tool calls because they&#x27;ve seen typescript code many more times.<p>HN Discussion: <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=45399204">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=45399204</a> <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=45386248">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=45386248</a><p>Deno provides a great sandbox environment for Typescript code execution because of its permissions system which made it easy to spin up code that only has access to fetch and network calls.<p>Stick an MCP proxy on top of that and you&#x27;ve got &quot;CodeMode&quot; (code intermixed with MCP tool calls) for more advanced workflow orchestration.<p><a href="https:&#x2F;&#x2F;github.com&#x2F;jx-codes&#x2F;codemode-mcp" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;jx-codes&#x2F;codemode-mcp</a><p>There&#x27;s a lot of things that can be improved here. Like a virtual file system for the agent to actually build up its solution instead of being forced to one shot the solution but the bones are there.

[Other] Show HN: Toolbrew – Free little tools without signups or ads I got tired of fighting through spammy tool sites just to do something simple, so I made Toolbrew in a few hours on Replit. Just a bunch of free little tools in one place. Text converters, SEO checks, video downloaders, that kind of stuff. No signups, no ads.<p>If there is a tool you wish existed, you can request it on the site and I will build it. Do your worst. Seriously, ANY tool.<p>Maybe it helps, maybe not. Enjoy!

[Other] Show HN: Curated gamedev specific search engine

[Other] Show HN: An open source Launchpad for macOS 26 An open sourced version of Launchpad that I enhanced, you can import from old system Launchpad (just one click), and most of things look same. There are also a lot of functions, like adjust &#x2F; display &#x2F; hide icon size and title, localize icons, game controller support, i18n, voice over, etc.<p>Still updating, open an issue if there are any problems. Hope this could help if someone updated to MacOS26 and not happy with new Launchpad :)<p>Thank you.

[API/SDK] Show HN: One API for all your SMTPs Hi HN,<p>I host my own mail infrastructure and don&#x27;t rely on third-party tools to send my mails. But in a microservice architecture, managing all the SMTP configs quickly becomes tiresome. After a while I&#x27;d always have my credentials and settings scattered in application-properties, bash scripts and environment files.<p>So I&#x27;ve build Brieferl, an app where you can add your SMTP servers and send emails through a single API with a simple JSON payload. You also get logs of when&#x2F;where emails were sent and HTML previews of messages.<p>I am interested in what you guys think about this. You can create a free account with just your email, add a SMTP server + API key and start sending. (There is no upsell, or paid plan yet)<p>This is super early, it works and I made it actually just for myself but a friend told me he‘d also love to use this, so I thought why not ask other developers what they think.<p>Is this something you’d use? Are there some features that would it more valuable for you? Or is this something only I’ve felt?

[Other] Property-Based Testing of OCaml 5's Runtime System [pdf]

[Other] Show HN: A web version of Pips game (NYT domino game) Hi everyone,<p>I’m an indie developer learning Next.js and a big fan of the NYT game Pips. Inspired by it, I built <a href="https:&#x2F;&#x2F;pipsgamer.com" rel="nofollow">https:&#x2F;&#x2F;pipsgamer.com</a> — a responsive web version of Pips with smooth gameplay on both desktop and mobile.<p>What makes this project different from NYT’s version is that you can play it infinitely under three difficulty levels: Easy &#x2F; Medium &#x2F; Hard.<p>This is the first time I’ve built a game. Along the way I ran into many difficulties: implementing the game logic, configuring the UI, matching layouts for small and large screens, etc. I spent many lonely nights and sometimes even doubted whether I could complete the whole project. After 24 days of persistent effort, the project is finally finished.<p>No signup required — just go and play. If you try it out I’d really appreciate your feedback: what you like, what bugs you see, what could be improved.<p>Thanks!

[Other] Show HN: FingerprinterJS – A tiny JavaScript library for browser fingerprints I made FingerprinterJS, a small library with no dependencies that creates browser fingerprints from signals like canvas, WebGL, audio, fonts, userAgent, and screen info.<p>It’s written in TypeScript, lets you enable&#x2F;disable collectors, add custom data, and includes a simple suspicious-activity score.<p>Would love feedback.

[Other] Genode OS Framework

[Other] Show HN: Macscope – I decide to built a better Cmd-Tab replacement for macOS Hi HN,<p>Macscope is a new window manager and and app switcher for macOS built on the philosophy of enhancing, not replacing, your existing muscle memory.<p>It works by augmenting the familiar Cmd+Tab workflow. A quick tap of your shortcut instantly switches between recent apps, just like you&#x27;re used to. A slightly longer hold, however, opens the full Macscope interface where you can manage all your open windows and tabs.<p>You can also use modifier shortcuts to enter Placement Modes, which let you instantly snap a selected window to the left&#x2F;right&#x2F;top&#x2F;bottom&#x2F; half of your screen.<p>Here are some of the key features:<p>- Unified Search &amp; Switch: A single interface to instantly find and switch to any window, browser tab (Safari, Chrome, Arc, etc.), or application just by typing.<p>- Live Previews: See a real-time preview of what&#x27;s inside each window so you know exactly where you&#x27;re going. You can also disable previews for a more minimal experience.<p>- Advanced Window Management: Go beyond just switching. Select multiple windows and arrange them into layouts like vertical&#x2F;horizontal splits or grids.<p>- Scopes: Save collections of app windows as a &quot;Scope&quot; and instantly restore that entire workspace later. It&#x27;s ideal for quickly switching between different projects or tasks.<p>It’s a native macOS app built with Swift and supports both Apple Silicon and Intel machines.<p>Launch Offer for HN:<p>There&#x27;s a free trial with 250 actions. For the Hacker News community, I&#x27;m offering a 50% discount on the lifetime license.<p>Website: <a href="https:&#x2F;&#x2F;macscope.app" rel="nofollow">https:&#x2F;&#x2F;macscope.app</a><p>Discord Community: <a href="https:&#x2F;&#x2F;discord.gg&#x2F;ehktEWr97K" rel="nofollow">https:&#x2F;&#x2F;discord.gg&#x2F;ehktEWr97K</a><p>I&#x27;ll be here all day to answer questions and would be grateful for any feedback. Thanks for checking it out!

[API/SDK] Show HN: Prism – Let browser agents access any app Hey HN, We’re Alex, Land, and Rajit. We’re building Prism (prismai.sh), a tool that helps browser agents authenticate onto websites with user credentials. Developers pass in credentials, Prism logs into a website on their behalf, and hands them back the cookies so they have an authenticated session. Here’s an example of how developers can use Prism to complete username&#x2F;password flows (<a href="https:&#x2F;&#x2F;youtu.be&#x2F;SEtVUnWnxuE" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;SEtVUnWnxuE</a>), and here’s an example of how developers can use Prism to complete login flows that require an OTP code (<a href="https:&#x2F;&#x2F;youtu.be&#x2F;fe9w9PvrwH0" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;fe9w9PvrwH0</a>).<p>We spoke to browser agent developers and saw people copying and pasting credentials and even credit card numbers directly into model system prompts. We were surprised that there wasn’t a better way to give agents access to websites on a human’s behalf. Moreover, we noticed that every company had to build infrastructure to manage OTP, TOTP, and MFA and that auth remained a significant hurdle in agent reliability. We wondered if this was a boring part of the problem of building web automations that someone could automate away.<p>We started working with Casco, an autonomous security testing company, to enable their agent to access customer sites. Before a pentest, Casco makes a request to Prism’s API specifying test user credentials, a domain, and a login method. For example, give me an authenticated session for the account rajit@prismai.sh for OpenAI via OTP code over email. Our agent logs in on their behalf (without exposing credentials to a model), and we download the cookies and send them back in the response.<p>To maintain speed and reliability, we use playwright in most cases to login (which gives us speed), and we fallback to AI on failure (which gives us reliability). We have a number of websites we support out of the box and add new scripts as the number of websites we need to support grows. We are working on a way for the agent to update the existing playwright script on failure, so our scripts always stay up to date.<p>To try our api, you can use our API playground docs.prismai.sh&#x2F;api-reference&#x2F;endpoint&#x2F;login to sign into x.com with the following API key: pk_54abb1cd0a637eb973ed690416e71a953e98f2ea839cf16529bbfa41a41bc016 .<p>We’d love to learn more about how other developers give agents access to their accounts. We look forward to everyone’s feedback and comments.

[Other] Show HN: Phishcan, Canada's first open and free threat intelligence platform Phishcan provides crucial threat intelligence, and it currently tracks phishing domains for:<p>• Scotiabank, Desjardins, RBC, Interac…<p>• Telecom providers, provincial power and health services...<p>• Federal &amp; provincial services, CRA, Canada Post, Service Canada, Revenue Québec...<p>How Phishcan works:<p>• Parsing millions of domains: Continuously scanning and analyzing vast numbers of domains to detect suspicious patterns and potential phishing sites.<p>• Monitoring threat actors : close watch on cyber‑criminal infrastructures and their new domain registrations.<p>• Data enrichment : adding contextual insights and connections to improve the information<p>• Feeds are updated every 12 hours.<p>• You can use the API freely at: <a href="https:&#x2F;&#x2F;phishcan.com&#x2F;api-docs" rel="nofollow">https:&#x2F;&#x2F;phishcan.com&#x2F;api-docs</a><p>Data is also available on: <a href="https:&#x2F;&#x2F;github.com&#x2F;Phishcan&#x2F;phishcan-data" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;Phishcan&#x2F;phishcan-data</a><p>I plan to improve the whole platform with more data during my free time!

[IDE/Editor] Rustroid, a Rust IDE for Android

[CLI Tool] Better Curl Saul: a lightweight API testing CLI focused on UX and simplicity

[Other] Show HN: A UI Library for the Web Focusing on accessibility, longevity, performance, and simplicity

[Other] Show HN: Dayflow – A git log for your day Hi HN! I&#x27;ve been building Dayflow, a macOS app that automatically tracks what you&#x27;re actually working on (not just which apps you have open).<p>Here&#x27;s what it does:<p>- It creates a semantic timeline of your day;<p>- It does it by understanding the content on your screen (with local or cloud VLMs);<p>- This allows you to see exactly where your time went without any manual logging.<p>Traditional time trackers tell you &quot;3 hours in Chrome&quot; which is not very helpful. Dayflow actually understands if you&#x27;re reading documentation, debugging code, or scrolling HN. Instead of &quot;Chrome: 3 hours&quot;, you get &quot;Reviewed PR comments: 45min&quot;, &quot;Read HN thread about Rust: 20min&quot;, &quot;Debugged auth flow: 1.5hr&quot;.<p>I was an early Rewind user but rarely used the retrieval feature. I built Dayflow because I saw other interesting uses for screen data. I find that it helps me stay on track while working - I check it every few hours and make sure I’m spending my time the way I intended - if I’m not, I try to course correct.<p>Here’s what you need to know about privacy:<p>- Run 100% locally using qwen2.5-vl-3b (~4GB model)<p>- No cloud uploads, no account<p>- Full source available under MIT license (<a href="https:&#x2F;&#x2F;github.com&#x2F;JerryZLiu&#x2F;Dayflow" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;JerryZLiu&#x2F;Dayflow</a>)<p>- Optional: BYO Gemini API key for better quality (stored in Keychain, with free-tier workaround to prevent training on your data)<p>The tech stack is pretty simple, SwiftUI with a local sqlite DB. Uses native macOS apis for efficient screen captures. Since most people who run LLMs locally already have their tool of choice (Ollama, LLMStudio, etc.), I decided to not embed an LLM into Dayflow.<p>By far the biggest challenge was adapting from SOTA vision models like Gemini 2.5 Pro to small, local models. My constraints were that it had to take up &lt;4GB of ram and have vision capabilities. I had to do a lot of evals to figure out that Qwen2.5VL-3B was the best balance of size and quality, but there was still a sizable tradeoff in quality that I had to accept. I also got creative with sampling rates and prompt chunking to deal with the 100x smaller context window. Processing a 15 minute segment takes ~32 local LLM calls vs 2 Gemini calls!<p>Here’s what I’m working on next:<p>Distillation: Using Gemini&#x27;s high-quality outputs as training data to teach a local model the patterns it needs, hopefully closing the quality gap.<p>Custom dashboards where you can track answers to any question like &quot;How long did I spend on HN?&quot; or &quot;Hours until my first deep work session of the day<p>I&#x27;d love to hear your thoughts, especially if you&#x27;ve struggled with productivity tracking or have ideas for what you&#x27;d want from a tool like this.

[DevOps] Show HN: Mosaic – A Kotlin framework for cleaner back end code Backend APIs often grow into large orchestration classes full of duplicated calls and manual concurrency.<p>I’ve been working on Mosaic, a Kotlin framework that composes responses out of small, request-scoped “tiles.” Each tile runs once per request, dependencies resolve automatically, and independent tiles execute in parallel without boilerplate.<p>It’s still early (v0.2.0), but working today for caching, concurrency, and testability. Curious to hear feedback on the approach.<p>GitHub: <a href="https:&#x2F;&#x2F;github.com&#x2F;Nick-Abbott&#x2F;Mosaic" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;Nick-Abbott&#x2F;Mosaic</a> Maven Central: org.buildmosaic:mosaic-core:0.2.0