Open Source

BlazePDF is a desktop PDF reader built for studying. It gives students one calm workspace for lecture slides, readings, textbook chapters, research papers, and past papers, so they can read, annotate, organize, and print in one app. The app works offline and needs no account for the desktop reader. Files stay on the student's computer, and reading, annotating, searching, and exporting all happen locally. Key Features Annotation tools include pen and marker strokes, word-aware highlights, text boxes, shapes, arrows, lines, and images. Tool presets restore your preferred color, width, and opacity with a single shortcut. Flow Mode supports keyboard-first annotation, so you can keep working without reaching for the mouse. Page tools add blank pages, import images, reorder pages, and export the edited PDF. Smart Duplex prepares two-sided printing for printers that need a manual second pass, with reload instructions. Poster Enlargement turns one large diagram into tiled sheets and previews how the pieces fit together. Who Should Use BlazePDF Students working through a full semester of slides, readings, and past papers. Revision-focused learners who highlight, search, and revisit key passages before exams. Anyone printing oversized study material, such as large diagrams that need tiling or two-sided booklets. Frequently Asked Questions What is BlazePDF? BlazePDF is a desktop PDF reader made for students, by students. It combines reading, annotating, organizing, searching, and printing in one offline workspace. Is BlazePDF free for students? The site offers a free download for students. Current plan options are listed on the download and plans page. Do I need an account to use BlazePDF? No. The desktop reader needs no account. Optional account and AI OCR features start only when you choose them. Is my document content private? Yes. Reading, annotating, searching native PDF text, and exporting happen locally on your desktop. BlazePDF does not use document content to train generalized AI models.

openTag is an open source AI coworker that lives in Slack and Lark. Tag it in a thread with a task, and a coding agent on your own computer does the work and replies there. It is built by first-tree.ai under the Apache 2.0 licence. There is no AI provider lock-in: bring a Claude or Codex subscription or any API key. Key Features Chat-first delegation: Tag openTag in any Slack or Lark thread and the task starts without leaving the conversation. Bring your own model: Run Claude Code, Codex, or Pi with your own subscription or API key, with no provider lock-in. Local execution: A small program on your Mac or Linux machine runs the agent, and openTag servers do not store your code by default. Context Tree memory: Team memory is markdown in a git repository inside your own GitHub organization, so it stays readable and versioned. 1000+ connectors: Agents reach GitHub, Notion, Linear, Jira, and Figma using your own credentials and minimal scope. Team mode: One agent serves a whole channel, and agents can hand work to each other and check progress. Who Should Use openTag Engineering teams that want issue triage, PR reviews, and status updates handled in team chat. Startups and solo maintainers who need extra hands without adding headcount. Privacy-conscious organizations that need agent memory to stay in their own GitHub organization. Frequently Asked Questions What is openTag? openTag is an open source AI coworker for Slack and Lark. You tag it in a thread, it runs a coding agent on your computer, and it replies with the result. Is openTag free? Yes. openTag is free to use, and you only pay for your own AI usage through your existing provider subscription or API key. Which apps does openTag support? It connects to Slack and Lark, and works with Claude Code, Codex, Pi, or any API key. Teams and Discord support is on the roadmap. Where does team memory live? By default openTag servers do not store your conversations, code, or memory. Memory lives in a git repository you host in your own GitHub organization.

FPVtune is a free, web-based automatic PID tuning tool for FPV drones. Every FPV pilot knows the pain of manual PID tuning — hours of test flights, analyzing blackbox logs, tweaking values, and repeating the cycle. FPVtune eliminates this tedious process entirely. Simply upload your Betaflight blackbox log file, and FPVtune analyzes your gyro data to identify noise patterns, oscillations, and filter performance. Within minutes, you get optimized PID and filter settings tailored to your specific quad setup. Works with all types of FPV builds including freestyle quads, racing drones, cinewhoops, and tiny whoops. Compatible with Betaflight and INAV flight controllers. Fix oscillations, reduce propwash, and achieve a locked-in feel without being a tuning expert. FPVtune is open source and completely free to use. No installation required — everything runs in your browser at fpvtune.com.

Made to code hard without feeling heavyClawie is built around a real terminal workspace, but the page now stays focused on what matters most: coding quality, easy flow, local power, and fast response.