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Show HN: Recall: Give Claude memory with Redis-backed persistent context

Hey HN! I'm José, and I built Recall to solve a problem that was driving me crazy.<p>The Problem: I use Claude for coding daily, but every conversation starts from scratch. I'd explain my architecture, coding standards, past decisions... then hit the context limit and lose everything. Next session? Start over.<p>The Solution: Recall is an MCP (Model Context Protocol) server that gives Claude persistent memory using Redis + semantic search. Think of it as long-term memory that survives context limits and session restarts.<p>How it works: - Claude stores important context as "memories" during conversations - Memories are embedded (OpenAI) and stored in Redis with metadata - Semantic search retrieves relevant memories automatically - Works across sessions, projects, even machines (if you use cloud Redis)<p>Key Features: - Global memories: Share context across all projects - Relationships: Link related memories into knowledge graphs - Versioning: Track how memories evolve over time - Templates: Reusable patterns for common workflows - Workspace isolation: Project A memories don't pollute Project B<p>Tech Stack: - TypeScript + MCP SDK - Redis for storage - OpenAI embeddings (text-embedding-3-small) - ~189KB bundle, runs locally<p>Current Stats: - 27 tools exposed to Claude - 10 context types (directives, decisions, patterns, etc.) - Sub-second semantic search on 10k+ memories - Works with Claude Desktop, Claude Code, any MCP client<p>Example Use Case: I'm building an e-commerce platform. I told Claude once: "We use Tailwind, prefer composition API, API rate limit is 1000/min." Now every conversation, Claude remembers and applies these preferences automatically.<p>What's Next (v1.6.0 in progress): - CI/CD pipeline with GitHub Actions - Docker support for easy deployment - Proper test suite with Vitest - Better error messages and logging<p>Try it:<p>npm install -g @joseairosa/recall # Add to claude_desktop_config.json # Start using persistent memory

Show HN: Recall: Give Claude memory with Redis-backed persistent context

Hey HN! I'm José, and I built Recall to solve a problem that was driving me crazy.<p>The Problem: I use Claude for coding daily, but every conversation starts from scratch. I'd explain my architecture, coding standards, past decisions... then hit the context limit and lose everything. Next session? Start over.<p>The Solution: Recall is an MCP (Model Context Protocol) server that gives Claude persistent memory using Redis + semantic search. Think of it as long-term memory that survives context limits and session restarts.<p>How it works: - Claude stores important context as "memories" during conversations - Memories are embedded (OpenAI) and stored in Redis with metadata - Semantic search retrieves relevant memories automatically - Works across sessions, projects, even machines (if you use cloud Redis)<p>Key Features: - Global memories: Share context across all projects - Relationships: Link related memories into knowledge graphs - Versioning: Track how memories evolve over time - Templates: Reusable patterns for common workflows - Workspace isolation: Project A memories don't pollute Project B<p>Tech Stack: - TypeScript + MCP SDK - Redis for storage - OpenAI embeddings (text-embedding-3-small) - ~189KB bundle, runs locally<p>Current Stats: - 27 tools exposed to Claude - 10 context types (directives, decisions, patterns, etc.) - Sub-second semantic search on 10k+ memories - Works with Claude Desktop, Claude Code, any MCP client<p>Example Use Case: I'm building an e-commerce platform. I told Claude once: "We use Tailwind, prefer composition API, API rate limit is 1000/min." Now every conversation, Claude remembers and applies these preferences automatically.<p>What's Next (v1.6.0 in progress): - CI/CD pipeline with GitHub Actions - Docker support for easy deployment - Proper test suite with Vitest - Better error messages and logging<p>Try it:<p>npm install -g @joseairosa/recall # Add to claude_desktop_config.json # Start using persistent memory

Show HN: Neural emotion matrix for NPCs

Hey! I built this system to humanize NPCs by giving them emotions using Rust and ML.<p>The system provides emotion coordinates (based on Russell's circumplex model) from text input or actions, with persistent emotional memory per entity. Think NPCs that remember how they feel about specific players or events.<p>I pre-trained a DistilBERT model on ~1k video game dialogues (Skyrim, Cyberpunk, etc.) and plan to extract and evaluate 100k+ dialogues soon. However studio/team can manually add dialogues to enrich their own dataset.<p>The matrix doesn't generate dialogue, it only analyzes content. When you pass text or an action, it returns emotion coordinates on the valence (pleasant/unpleasant) and arousal(energetic/calm) scale. For example:<p>- [0.00, 0.00] = neutral<p>- [0.29, 0.80] = excited<p>- [-0.50, -0.30] = sad/tired<p>I made a quick visualizer here to help understand <a href="https://valence-arousal-visualizer.vercel.app/" rel="nofollow">https://valence-arousal-visualizer.vercel.app/</a><p>The system helps select which dialogue/action to play based on emotional state:<p>- Player says something bad to NPC → system detects negative valence → game picks from "angry dialogue pool"<p>- NPC remembers past positive interactions → system returns positive valence → friendlier responses available<p>So, the devs still write the dialogues or choose the next actions, but the matrix helps manage NPC emotional states and memory dynamically.<p>Here's the project structure to better understand how it works:<p>- src/config: Helper utilities for NPC configuration setup<p>- src/module: The core engine with emotion prediction, memory storage, and entity management<p>- src/api: FFI layer with pub extern "C" to bridge our modules with C/C++ game engines and modding tools (Unity, Unreal, etc.)<p>To implement it, just call `build.sh`, it will create DLL files that you can use to call the matrix functions directly in C++/C/C#.<p>I'd love feedback on code quality and overall architecture.<p>Feel free to be honest about the good, the bad, and the ugly. PRs welcome if you want to contribute!

Show HN: MARS – Personal AI robot for builders (< $2k)

Hey, we’re Axel and Vignesh, cofounders of Innate (<a href="https://www.innate.bot/">https://www.innate.bot/</a>). We just launched MARS, a general-purpose robot with an open onboard agentic OS built on top of ROS2.<p>Overview: <a href="https://youtu.be/GEOMYDXv6pE" rel="nofollow">https://youtu.be/GEOMYDXv6pE</a><p>Control demo: <a href="https://youtu.be/_Cw5fGa8i3s" rel="nofollow">https://youtu.be/_Cw5fGa8i3s</a><p>Videos of autonomous use-cases: <a href="https://docs.innate.bot/welcome/mars-example-use-cases">https://docs.innate.bot/welcome/mars-example-use-cases</a><p>Quickstart: <a href="https://docs.innate.bot/welcome/mars-quick-start">https://docs.innate.bot/welcome/mars-quick-start</a>.<p>Our last thread: <a href="https://news.ycombinator.com/item?id=42451707">https://news.ycombinator.com/item?id=42451707</a><p>When we started we felt there is currently no good affordable general-purpose that anyone can build on. There’s no lack of demand: hugging face’s SO-100 and LeKiwi are pretty clear successes already; but the hardware is unreliable, the software experience is barebone and keeps changing, and you often need to buy hidden extras to make them work (starting with a computer with a good gpu). The Turtlebots were good, but are getting outdated.<p>The open-source hobbyist movement lacks really good platforms to build on, and we wanted something robust and accessible. MARS is our attempt at making a first intuitive AI robot for everyone.<p>What it is:<p>- It comes assembled and calibrated<p>- Has onboard compute with a jetson orin nano 8gb<p>- a 5DoF arm with a wrist camera<p>- Sensors: RGBD wide-angle cam, 2D LiDAR, speakers<p>- Control via a dedicated app and a leader arm that plugs in iPhone and Android<p>- 2 additional USB ports + GPIO pins for extra sensors or effectors.<p>- And our novel SDK called BASIC that allows to run it like an AI agent with VLAs.<p>It boots in a minute, can be controlled via phone, programmable in depth with a PC, and the onboard agent lets it see, talk, plan, and act in real-time.<p>Our SDK BASIC allows to create “behaviors” (our name for programs) ranging from a simple hello world to a very complex long-horizon task involving reasoning, planning, navigation and manipulation. You can create skills that behaviors can run autonomously by training the arm or writing code tools, like for an AI agent.<p>You can also call the ROS2 topics to control the robot at a low-level. And anything created on top of this SDK can be easily shared with anyone else by just sharing the files.<p>This is intended for hobbyist builders and education, and we would love to have your feedback!<p>p.s. If you want to try it, there’s a temporary code HACKERNEWS-INNATE-MARS that lowers the price to $1,799.<p>p.p.s The hardware and software will be open-sourced too, if some of you want to contribute or help us prepare it properly feel free to join our discord at <a href="https://discord.gg/YvqQbGKH" rel="nofollow">https://discord.gg/YvqQbGKH</a>

Show HN: MARS – Personal AI robot for builders (< $2k)

Hey, we’re Axel and Vignesh, cofounders of Innate (<a href="https://www.innate.bot/">https://www.innate.bot/</a>). We just launched MARS, a general-purpose robot with an open onboard agentic OS built on top of ROS2.<p>Overview: <a href="https://youtu.be/GEOMYDXv6pE" rel="nofollow">https://youtu.be/GEOMYDXv6pE</a><p>Control demo: <a href="https://youtu.be/_Cw5fGa8i3s" rel="nofollow">https://youtu.be/_Cw5fGa8i3s</a><p>Videos of autonomous use-cases: <a href="https://docs.innate.bot/welcome/mars-example-use-cases">https://docs.innate.bot/welcome/mars-example-use-cases</a><p>Quickstart: <a href="https://docs.innate.bot/welcome/mars-quick-start">https://docs.innate.bot/welcome/mars-quick-start</a>.<p>Our last thread: <a href="https://news.ycombinator.com/item?id=42451707">https://news.ycombinator.com/item?id=42451707</a><p>When we started we felt there is currently no good affordable general-purpose that anyone can build on. There’s no lack of demand: hugging face’s SO-100 and LeKiwi are pretty clear successes already; but the hardware is unreliable, the software experience is barebone and keeps changing, and you often need to buy hidden extras to make them work (starting with a computer with a good gpu). The Turtlebots were good, but are getting outdated.<p>The open-source hobbyist movement lacks really good platforms to build on, and we wanted something robust and accessible. MARS is our attempt at making a first intuitive AI robot for everyone.<p>What it is:<p>- It comes assembled and calibrated<p>- Has onboard compute with a jetson orin nano 8gb<p>- a 5DoF arm with a wrist camera<p>- Sensors: RGBD wide-angle cam, 2D LiDAR, speakers<p>- Control via a dedicated app and a leader arm that plugs in iPhone and Android<p>- 2 additional USB ports + GPIO pins for extra sensors or effectors.<p>- And our novel SDK called BASIC that allows to run it like an AI agent with VLAs.<p>It boots in a minute, can be controlled via phone, programmable in depth with a PC, and the onboard agent lets it see, talk, plan, and act in real-time.<p>Our SDK BASIC allows to create “behaviors” (our name for programs) ranging from a simple hello world to a very complex long-horizon task involving reasoning, planning, navigation and manipulation. You can create skills that behaviors can run autonomously by training the arm or writing code tools, like for an AI agent.<p>You can also call the ROS2 topics to control the robot at a low-level. And anything created on top of this SDK can be easily shared with anyone else by just sharing the files.<p>This is intended for hobbyist builders and education, and we would love to have your feedback!<p>p.s. If you want to try it, there’s a temporary code HACKERNEWS-INNATE-MARS that lowers the price to $1,799.<p>p.p.s The hardware and software will be open-sourced too, if some of you want to contribute or help us prepare it properly feel free to join our discord at <a href="https://discord.gg/YvqQbGKH" rel="nofollow">https://discord.gg/YvqQbGKH</a>

Show HN: MARS – Personal AI robot for builders (< $2k)

Hey, we’re Axel and Vignesh, cofounders of Innate (<a href="https://www.innate.bot/">https://www.innate.bot/</a>). We just launched MARS, a general-purpose robot with an open onboard agentic OS built on top of ROS2.<p>Overview: <a href="https://youtu.be/GEOMYDXv6pE" rel="nofollow">https://youtu.be/GEOMYDXv6pE</a><p>Control demo: <a href="https://youtu.be/_Cw5fGa8i3s" rel="nofollow">https://youtu.be/_Cw5fGa8i3s</a><p>Videos of autonomous use-cases: <a href="https://docs.innate.bot/welcome/mars-example-use-cases">https://docs.innate.bot/welcome/mars-example-use-cases</a><p>Quickstart: <a href="https://docs.innate.bot/welcome/mars-quick-start">https://docs.innate.bot/welcome/mars-quick-start</a>.<p>Our last thread: <a href="https://news.ycombinator.com/item?id=42451707">https://news.ycombinator.com/item?id=42451707</a><p>When we started we felt there is currently no good affordable general-purpose that anyone can build on. There’s no lack of demand: hugging face’s SO-100 and LeKiwi are pretty clear successes already; but the hardware is unreliable, the software experience is barebone and keeps changing, and you often need to buy hidden extras to make them work (starting with a computer with a good gpu). The Turtlebots were good, but are getting outdated.<p>The open-source hobbyist movement lacks really good platforms to build on, and we wanted something robust and accessible. MARS is our attempt at making a first intuitive AI robot for everyone.<p>What it is:<p>- It comes assembled and calibrated<p>- Has onboard compute with a jetson orin nano 8gb<p>- a 5DoF arm with a wrist camera<p>- Sensors: RGBD wide-angle cam, 2D LiDAR, speakers<p>- Control via a dedicated app and a leader arm that plugs in iPhone and Android<p>- 2 additional USB ports + GPIO pins for extra sensors or effectors.<p>- And our novel SDK called BASIC that allows to run it like an AI agent with VLAs.<p>It boots in a minute, can be controlled via phone, programmable in depth with a PC, and the onboard agent lets it see, talk, plan, and act in real-time.<p>Our SDK BASIC allows to create “behaviors” (our name for programs) ranging from a simple hello world to a very complex long-horizon task involving reasoning, planning, navigation and manipulation. You can create skills that behaviors can run autonomously by training the arm or writing code tools, like for an AI agent.<p>You can also call the ROS2 topics to control the robot at a low-level. And anything created on top of this SDK can be easily shared with anyone else by just sharing the files.<p>This is intended for hobbyist builders and education, and we would love to have your feedback!<p>p.s. If you want to try it, there’s a temporary code HACKERNEWS-INNATE-MARS that lowers the price to $1,799.<p>p.p.s The hardware and software will be open-sourced too, if some of you want to contribute or help us prepare it properly feel free to join our discord at <a href="https://discord.gg/YvqQbGKH" rel="nofollow">https://discord.gg/YvqQbGKH</a>

Show HN: I'm building a browser for reverse engineers

Show HN: I'm building a browser for reverse engineers

Show HN: I'm building a browser for reverse engineers

Show HN: Timelinize – Privately organize your own data from everywhere, locally

Hey HN -- thanks for showing interest in this. Happy to collaborate on this project. I'm hoping to get it stable soon so my own family can start using it.<p>I've been working on this for about 10+ years, nights and weekends. It's been really slow going since I only have my own personal data to test it with.<p>I just don't love that my data is primarily stored on someone else's computer up in the cloud. I want my own local copy at least. And while I can download exports from my various accounts, I don't want them to just gather dust and rot on my hard drive.<p>So, Timelinize helps keep that data alive and relevant and in my control. I don't have as much worry if my cloud accounts go away. Hopefully you'll find it useful, and I hope we can collaborate.<p>(PS. I'm open to changing the name. Never really liked this one...)

Show HN: Timelinize – Privately organize your own data from everywhere, locally

Hey HN -- thanks for showing interest in this. Happy to collaborate on this project. I'm hoping to get it stable soon so my own family can start using it.<p>I've been working on this for about 10+ years, nights and weekends. It's been really slow going since I only have my own personal data to test it with.<p>I just don't love that my data is primarily stored on someone else's computer up in the cloud. I want my own local copy at least. And while I can download exports from my various accounts, I don't want them to just gather dust and rot on my hard drive.<p>So, Timelinize helps keep that data alive and relevant and in my control. I don't have as much worry if my cloud accounts go away. Hopefully you'll find it useful, and I hope we can collaborate.<p>(PS. I'm open to changing the name. Never really liked this one...)

Show HN: Timelinize – Privately organize your own data from everywhere, locally

Hey HN -- thanks for showing interest in this. Happy to collaborate on this project. I'm hoping to get it stable soon so my own family can start using it.<p>I've been working on this for about 10+ years, nights and weekends. It's been really slow going since I only have my own personal data to test it with.<p>I just don't love that my data is primarily stored on someone else's computer up in the cloud. I want my own local copy at least. And while I can download exports from my various accounts, I don't want them to just gather dust and rot on my hard drive.<p>So, Timelinize helps keep that data alive and relevant and in my control. I don't have as much worry if my cloud accounts go away. Hopefully you'll find it useful, and I hope we can collaborate.<p>(PS. I'm open to changing the name. Never really liked this one...)

Show HN: I've build a platform for writing technical/scientific documents

Show HN: I've build a platform for writing technical/scientific documents

Show HN: I've build a platform for writing technical/scientific documents

Show HN: Kent Dybvig's Scheme Machine in 400 Lines of C (Heap-Memory Model)

Show HN: Kent Dybvig's Scheme Machine in 400 Lines of C (Heap-Memory Model)

Show HN: Kent Dybvig's Scheme Machine in 400 Lines of C (Heap-Memory Model)

Show HN: Write It Down – Personal finance tracker

Everyone’s chasing AI hype. I built a Google Sheet and it quietly took off.<p>In 2020, I made it to track my own finances for income, expenses, savings, yearly summaries etc. I shared it once on Reddit, forgot about it for a year… When I checked back, it had over 130k views and I was honestly stoked!<p>No launch. No funding. No AI. Just a spreadsheet people actually stick with and find useful.<p>I finally gave it a proper home: write-it-down.com Now, more than 2,300 people use it.<p>It’s intentionally boring and that’s why it works.<p>People don’t always need AI. They just need something that actually solves their problem. This isn’t a billion-dollar startup of course, but it taught me more about building products than almost anything else.<p>Build something useful. Solve a real problem. Even if it’s just a simple spreadsheet.<p>So, what’s the most “boring” thing you’ve built that found unexpected traction?

Show HN: Write It Down – Personal finance tracker

Everyone’s chasing AI hype. I built a Google Sheet and it quietly took off.<p>In 2020, I made it to track my own finances for income, expenses, savings, yearly summaries etc. I shared it once on Reddit, forgot about it for a year… When I checked back, it had over 130k views and I was honestly stoked!<p>No launch. No funding. No AI. Just a spreadsheet people actually stick with and find useful.<p>I finally gave it a proper home: write-it-down.com Now, more than 2,300 people use it.<p>It’s intentionally boring and that’s why it works.<p>People don’t always need AI. They just need something that actually solves their problem. This isn’t a billion-dollar startup of course, but it taught me more about building products than almost anything else.<p>Build something useful. Solve a real problem. Even if it’s just a simple spreadsheet.<p>So, what’s the most “boring” thing you’ve built that found unexpected traction?