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You use AI every day. A year of it should add up to something, and right now it doesn't. Every new chat starts from zero.
Second Brain is a memory layer that runs in your own Cloudflare account. Claude, ChatGPT, Cursor, Windsurf and any other MCP client read and write the same store, so what you work out in one tool is there in the next one.
Getting things in
Getting things back
Recall is semantic, not keyword. Memories link to each other, so a multi-hop search surfaces the reasoning behind a decision, not just the decision.
Entries carry a status (canonical, draft, deprecated) so an agent knows which version of a fact to trust.
Contradictions get flagged for a human to settle instead of quietly overwritten.
Where it lives
Your Cloudflare account: Workers, D1 and Vectorize.
Typical personal use sits inside Cloudflare's free tier. Open source on GitHub. No account with us, and nothing routes through our infrastructure.
Setup
Signed desktop app for Mac and Windows, one-click Cloudflare deploy, or clone the repo and run wrangler.
CodeSandbox TheSecondBrain.devTheSecondBrain.dev's answer:
Most AI memory tools store your context on their servers. This one deploys into your own Cloudflare account, so the memory is yours in a literal sense: your database, your vectors, your billing. We can't read it because we never have it.
The other difference is recall:
TheSecondBrain.dev's answer:
It works everywhere you work. Claude, ChatGPT, Cursor, Windsurf, Codex, any MCP client. Most memory tools only remember what happened inside their own app, so you end up with three AI tools holding three different versions of you.
You own the deployment. One-click deploy to Cloudflare, or a signed desktop installer if you'd rather not touch a terminal. Typical personal use sits inside Cloudflare's free tier, so there's no subscription to cancel and no vendor to migrate off later.
It's open source. MIT licensed. Read the code, fork it, extend it. Nothing about how your memory is stored or retrieved is a black box.
TheSecondBrain.dev's answer:
People who already live in these tools. They have an Obsidian vault or a Notion workspace, they're in Claude or ChatGPT every day, and some of them are in Cursor too. They're not casual users and they're not necessarily developers. They've built a system, and they've noticed the system doesn't talk to itself.
The shared frustration isn't "AI forgets." It's that a year of real thinking, hours of working through actual problems, hasn't left anything behind. Every conversation is good and then it's gone, and a month later they're figuring out the same thing from scratch.
They also tend to care where their work sits. Not privacy absolutists, just people who'd rather their own thinking accumulate in an account they control than in someone else's product they might have to leave.
TheSecondBrain.dev's answer:
I was using Claude, ChatGPT and Cursor every day and re-explaining the same projects to each of them. A year of that adds up to nothing. The decisions I'd worked out in one tool simply didn't exist in the next one.
I built it for myself first, on Cloudflare because I already had an account and the free tier meant I could run it without thinking about cost. Then I open sourced it, and what people asked for shaped what it became. The desktop app exists because a user on Product Hunt asked for a path that didn't involve a terminal, and she was right to ask.
I still use it every day. Most of the roadmap comes from hitting the limits of my own memory layer.
TheSecondBrain.dev's answer:
TheSecondBrain.dev's answer:
Based on our record, CodeSandbox seems to be more popular. It has been mentiond 313 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
To begin, you can start creating your own react app using the command line or can directly go to CodeSandbox if you want to skip using the command line which is faster. CodeSandbox is an online code editor and prototype tool that speeds up the creation and sharing of web apps where you can directly deploy your app without any hustle. - Source: dev.to / 3 months ago
To begin, you can create a react app using the command line or any code editor (e.g., VSCode). You can also try using CodeSandbox as an online code editor that is simple to use and allows you to deploy your code. - Source: dev.to / 3 months ago
If you are in a rush to open unknown repos, use GitHub Codespaces or codesandbox with Copilot or another AI integration to analyze the repo for malicious intent and to run it in a safe environment. - Source: dev.to / 8 months ago
CodeSandbox Examples: Check out CodeSandbox for live projects using Shadcn UI. Itโs a great way to see the toolkit in action. - Source: dev.to / over 1 year ago
I am thankful for a platform like CodeSandbox because it allows me to offload majority of the processing power and memory resources to the cloud. With a local VS Code installed, I can tunnel in via a remote connection to work on my projects, tinker, or do a deep-dive on certain topics; all while ensuring that the RPi 4 still has sufficient resources left to run other things in the background. - Source: dev.to / over 1 year ago
CodePen - A front end web development playground.
ChainMemory - Portable, verifiable memory for AI agents โ works across ChatGPT, Claude, Gemini and any MCP client
replit - Code, create, andlearn together. Use our free, collaborative, in-browser IDE to code in 50+ languages โ without spending a second on setup.
Agentmemory - Persistent memory for Claude Code, Codex & coding agents
JSFiddle - Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.
OpenMemory MCP - Your private, local memory layer for all AI tools