Show HN: Fluxer – open-source Discord-like chat https://ift.tt/KNUt3WG

Show HN: Fluxer – open-source Discord-like chat Hey HN, and happy new year! I'm Hampus Kraft [1], a 22-year-old software developer nearing completion of my BSc in Computer Engineering at KTH Royal Institute of Technology in Sweden. I've been working on Fluxer on and off for about 5 years, but recently decided to work on it full-time and see how far it could take me. Fluxer is an open source [2] communication platform for friends, groups, and communities (text, voice, and video). It aims for "modern chat app" feature coverage with a familiar UX, while being developed in the open and staying FOSS (AGPLv3). The codebase is largely written in TypeScript and Erlang. Try it now (no email or password required): https://ift.tt/HcQ5G8s – this creates an "unclaimed account" (date of birth only) so you can explore the platform. Unclaimed accounts can create/join communities but have some limitations. You can claim your account with email + password later if you want. I've developed this solo , with limited capital from some early supporters and testers. Please keep this in mind if you find what I offer today lacking; I know it is! I'm sharing this now to find contributors and early supporters who want to help shape this into the chat app you actually want. ~~~ Fluxer is not currently end-to-end encrypted, nor is it decentralised or federated. I'm open to implementing E2EE and federation in the future, but they're complex features, and I didn't want to end up like other community chat apps [3] that get criticised for broken core functionality and missing expected features while chasing those goals. I'm most confident on the backend and web app, so that's where I've focused. After some frustrating attempts with React Native, I'm sticking with a mobile PWA for now (including push notification support) while looking into Skip [4] for a true native app. If someone with more experience in native dev has any thoughts, let me know! Many tech-related communities that would benefit from not locking information into walled gardens still choose Discord or Slack over forum software because of the convenience these platforms bring, a choice that is often criticised [5][6][7]. I will not only work on adding forums and threads, but also enable opt-in publishing of forums to the open web, including RSS/Atom feeds, to give you the best of both worlds. ~~~ I don't intend to license any part of the software under anything but the AGPLv3, limit the number of messages [8], or have an SSO tax [9]. Business-oriented features like SSO will be prioritised on the roadmap with your support. You'd only pay for support and optionally for sponsored features or fixes you'd like prioritised. I don't currently plan on SaaS, but I'm open to support and maintenance contracts. ~~~ I want Fluxer to become an easy-to-deploy, fully FOSS Discord/Slack-like platform for companies, communities, and individuals who want to own their chat infrastructure, or who wish to support an independent and bootstrapped hosted alternative. But I need early adopters and financial support to keep working on it full-time. I'm also very interested in code contributors since this is a challenging project to work on solo. My email is hampus@fluxer.app. ~~~ There’s a lot more to be said; I’ll be around in the comments to answer questions and fix things quickly if you run into issues. Thank you, and wishing you all the best in the new year! [1] https://ift.tt/9RxGehE [2] https://ift.tt/I4NliQm [3] https://ift.tt/iCxyNXW [4] https://skip.tools/ [5] https://ift.tt/LZS1GQv [6] https://ift.tt/FIKJiRt [7] https://ift.tt/j27PHQW [8] https://ift.tt/VOF3xWh [9] https://sso.tax/ https://fluxer.app January 3, 2026 at 01:30AM

Show HN: I mapped System Design concepts to AI Prompts to stop bad code https://ift.tt/qcePGzs

Show HN: I mapped System Design concepts to AI Prompts to stop bad code https://ift.tt/9hrJyKQ January 3, 2026 at 12:15AM

Show HN: Feature detection exploration in Lidar DEMs via differential decomp https://ift.tt/vXkeO9w

Show HN: Feature detection exploration in Lidar DEMs via differential decomp I'm not a geospatial expert — I work in AI/ML. This started when I was exploring LiDAR data with agentic assitince and noticed that different signal decomposition methods revealed different terrain features. The core idea: if you systematically combine decomposition methods (Gaussian, bilateral, wavelet, morphological, etc.) with different upsampling techniques, each combination has characteristic "failure modes" that selectively preserve or eliminate certain features. The differences between outputs become feature-specific filters. The framework tests 25 decomposition × 19 upsampling methods across parameter ranges — about 40,000 combinations total. The visualization grid makes it easy to compare which methods work for what. Built in Cursor with Opus 4.5, NumPy, SciPy, scikit-image, PyWavelets, and OpenCV. Apache 2.0 licensed. I'd appreciate feedback from anyone who actually works with elevation data. What am I missing? What's obvious to practitioners that I wouldn't know? https://ift.tt/ebXoNxj January 1, 2026 at 05:59AM

Show HN: VectorDBZ, a desktop GUI for vector databases https://ift.tt/ZVhpLNS

Show HN: VectorDBZ, a desktop GUI for vector databases Hi HN, I built VectorDBZ, a cross-platform desktop app for exploring and analyzing vector databases like Qdrant, Weaviate, Milvus, and ChromaDB. It lets you browse collections, inspect vectors and metadata, run similarity searches, and visualize embeddings without writing custom scripts. GitHub (downloads and issues): https://ift.tt/c5foL18 Feedback welcome. If it’s useful, starring the repo helps keep me motivated. Thanks. https://ift.tt/c5foL18 January 1, 2026 at 08:55PM

Show HN: A Prompt-Injection Firewall for AI Agents and RAG Pipelines https://ift.tt/N2cOHFr

Show HN: A Prompt-Injection Firewall for AI Agents and RAG Pipelines We built SafeBrowse — an open-source prompt-injection firewall for AI systems. Instead of relying on better prompts, SafeBrowse enforces a hard security boundary between untrusted web content and LLMs. It blocks hidden instructions, policy violations, and poisoned data before the AI ever sees it. Features: • Prompt injection detection (50+ patterns) • Policy engine (login/payment blocking) • Fail-closed by design • Audit logs & request IDs • Python SDK (sync + async) • RAG sanitization PyPI: pip install safebrowse Looking for feedback from AI infra, security, and agent builders. January 1, 2026 at 02:31AM

Show HN: A web-based lighting controller built because my old became a brick https://ift.tt/LtKFM6s

Show HN: A web-based lighting controller built because my old became a brick I’m a student and I built this because my old lightning controller (DMX) became a brick after the vendor’s control software was deprecated in 2025. My focus was entirely on developing a robust backend architecture to guarantee maximum performance. Everything is released under GPLv3. The current frontend is just a "vibecoded" dashboard made with plain HTML and JavaScript to keep rendering latency as low as possible. In earlier versions Svelte was used. Svelte added too much complexity for an initial mvp. Video: https://ift.tt/S5TiRwD Repo: https://ift.tt/BPoTlGR Technical Details: The system uses a distributed architecture where a FastAPI server manages the state in a Redis. State changes are pushed via WebSockets to Raspberry Pi gateways, which then independently maintain the constant 44Hz binary stream to the lights. This "push model" saves massive amounts of bandwidth and ensures low latency. In a stress test, I processed 10 universes (5,120 channels) at 44Hz with zero packet loss (simulated). An OTP-based pairing makes the setup extremely simple (plug-and-play). I’m looking forward to your feedback on the architecture and the Redis approach! Happy New Year! https://ift.tt/BPoTlGR December 31, 2025 at 10:16PM

Show HN: Fleet / Event manager for Star Citizen MMO https://ift.tt/ULVMAlu

Show HN: Fleet / Event manager for Star Citizen MMO I built an open-source org management platform for Star Citizen, a space MMO where player orgs can have 50K+ members managing fleets worth millions. https://scorg.org The problem: SC's official tools won't launch until 2026, but players need to coordinate now - track 100+ ship fleets, schedule ops across timezones, manage alliances, and monitor voice activity during battles. Interesting challenges solved: 1. Multi-org data isolation - Users join multiple orgs, so every query needs scoping. 2. Canvas + Firebase Storage CORS - Couldn't export fleet layouts as PNG. Solution: fetch images as blobs, convert to base64 data URLs, then draw to canvas. No CORS config needed. 3. Discord bot - Built 4 microservices (VoiceActivityTracker, EventNotifier, ChannelManager, RoleSync) sharing Firebase state. Auto-creates channels for ops, cleans up when done. Features: role-based access, event calendar with RSVP, LFG matchmaking, drag-and-drop fleet builder, economy tools, alliance system, analytics dashboard, mobile-responsive. ~15 pages, fully functional. Custom military-inspired UI (monospace, gold accents). January 1, 2026 at 12:48AM