Show HN: How context engineering works, a runnable reference https://ift.tt/rEBgj3Q

Show HN: How context engineering works, a runnable reference I've been presenting at local meetups about Context Engineering, RAG, Skills, etc.. I even have a vbrownbag coming up on LinkedIn about this topic so I figured I would make a basic example that uses bedrock so I can use it in my talks or vbrownbags. Hopefully it's useful. https://ift.tt/iKnxm2z April 17, 2026 at 10:20PM

Show HN: Newsmaps.io a map of how news topics are covered by different countries https://ift.tt/HW3FCY1

Show HN: Newsmaps.io a map of how news topics are covered by different countries https://ift.tt/dnpCa6U April 20, 2026 at 01:02AM

Show HN: A privacy-first, local-LLM note app for iOS (Google Keep alternative) https://ift.tt/V5spmgC

Show HN: A privacy-first, local-LLM note app for iOS (Google Keep alternative) https://ift.tt/Jj5uQKN April 19, 2026 at 08:59PM

Show HN: Free PDF redactor that runs client-side https://ift.tt/RGUM9d6

Show HN: Free PDF redactor that runs client-side I recently needed to verify past employment and to do so I was going to upload paystubs from a previous employer, however I didn't want to share my salary in that role. I did a quick search online and most sites required sign-up or weren't clear about document privacy. I conceded and signed up for a free trial of Adobe Acrobat so I could use their PDF redaction feature. I figured there should be a dead simple way of doing this that's private, so I decided to create it myself. What this does is rasterize each page to an image with your redactions burned in, then it rebuilds the PDF so the text layer is permanently destroyed and not just covered up and easily retrievable. I welcome any and all feedback as this is my first live tool, thanks! https://redactpdf.net April 19, 2026 at 10:39PM

Show HN: AI Subroutines – Run automation scripts inside your browser tab https://ift.tt/U4DT1SK

Show HN: AI Subroutines – Run automation scripts inside your browser tab We built AI Subroutines in rtrvr.ai. Record a browser task once, save it as a callable tool, replay it at: zero token cost, zero LLM inference delay, and zero mistakes. The subroutine itself is a deterministic script composed of discovered network calls hitting the site's backend as well as page interactions like click/type/find. The key architectural decision: the script executes inside the webpage itself, not through a proxy, not in a headless worker, not out of process. The script dispatches requests from the tab's execution context, so auth, CSRF, TLS session, and signed headers get added to all requests and propagate for free. No certificate installation, no TLS fingerprint modification, no separate auth stack to maintain. During recording, the extension intercepts network requests (MAIN-world fetch/XHR patch + webRequest fallback). We score and trim ~300 requests down to ~5 based on method, timing relative to DOM events, and origin. Volatile GraphQL operation IDs are detected and force a DOM-only fallback before they break silently on the next run. The generated code combines network calls with DOM actions (click, type, find) in the same function via an rtrvr.* helper namespace. Point the agent at a spreadsheet of 500 rows and with just one LLM call parameters are assigned and 500 Subroutines kicked off. Key use cases: - record sending IG DM, then have reusable and callable routine to send DMs at zero token cost - create routine getting latest products in site catalog, call it to get thousands of products via direct graphql queries - setup routine to file EHR form based on parameters to the tool, AI infers parameters from current page context and calls tool - reuse routine daily to sync outbound messages on LinkedIn/Slack/Gmail to a CRM using a MCP server We see the fundamental reason that browser agents haven't taken off is that for repetitive tasks going through the inference loop is unnecessary. Better to just record once, and get the LLM to generate a script leveraging all the possible ways to interact with a site and the wider web like directly calling backed API's, interacting with the DOM, and calling 3P tools/APIs/MCP servers. https://ift.tt/50OqDWg April 18, 2026 at 01:03AM

Show HN: WebGL Liminal Space https://ift.tt/y7LlFDA

Show HN: WebGL Liminal Space Fun little liminal space game I made this week learning webGL. https://ift.tt/YPyFgtD https://liminal-dwsw5.ondigitalocean.app/ April 18, 2026 at 09:10PM

Show HN: Mind-OS – First free online AI dependency self‑assessment https://ift.tt/SpGcJ0k

Show HN: Mind-OS – First free online AI dependency self‑assessment https://iamalex-afk.github.io/human-os-patch-33-protocols/ April 18, 2026 at 01:40AM