epicenter

ntirely in TypeScript, which provided 80+ Unix commands (awk, sed, grep, jq, find, sqlite3, curl, etc.) to run against the same data the editor uses. Shell commands and the UI hit the same underlying CRDTs. $ echo "# Meeting notes" > /notes/2026-04-06.md $ mkdir /notes/archive $ mv /notes/2026-04-06.md /notes/archive/ $ open /notes/archive/2026-04-06.md Those commands create and move real files that immediately appear in the editor's file tree. The best part is that all of this works in both browser and server-side contexts, since yjs (https://github.com/yjs/yjs) is isomorphic. Under the hood, metadata (name, parent, timestamps) lives in a versioned CRDT table. Document content lives in a separate Y.Doc per file, so the directory index syncs without pulling every document body. Sync uses the Yjs protocol over WebSocket, with Cloudflare Durable Objects persisting an append-only SQLite update log. Everything is encrypted end-to-end with XChaCha20-Poly1305. Keys derived via HKDF-SHA256; the sync server sees only the ciphertext. More features: CodeMirror 6 with Yjs collaboration binding, `[[` internal links that store file IDs (renames don't break them), SQLite FTS5 search, AI chat with tool-call approval UI, and Vim mode. Opensidian itself is a demo. For the last six months, I've been working on the infrastructure underneath: `@epicenter/workspace` (typed CRDT tables with versioning, migrations, encryption, and sync) and `@epicenter/filesystem` (a POSIX filesystem layer over Yjs). I'll be writing more about those APIs separately and integrating them into more apps in the ecosystem (including Whispering). The idea is that anyone can build local-first apps on the same foundation: notes, task managers, knowledge bases, etc., while solving the most difficult problems of local-first sync. The UI is rough, and the feature set is thin compared to Obsidian; this isn't trying to replace it today. But I'm excited for what the future of personal computing tools could look like! MIT licensed. Would love feedback, ideas, and roasts. Source: https://github.com/EpicenterHQ/epicenter/tree/main/apps/open... Discord: https://go.epicenter.so/discord

need to match the UX of paid, closed-software alternatives. I hope Whispering is near that point. I use it for several hours a day, from coding to thinking out loud while carrying pizza boxes back from the office. Here’s an overview: https://www.youtube.com/watch?v=1jYgBMrfVZs, and here’s how I personally am using it with Claude Code these days: https://www.youtube.com/watch?v=tpix588SeiQ. There are plenty of transcription apps out there, but I hope Whispering adds some extra competition from the OSS ecosystem (one of my other OSS favorites is Handy https://github.com/cjpais/Handy). Whispering has a few tricks up its sleeve, like a voice-activated mode for hands-free operation (no button holding), and customizable AI transformations with any prompt/model. Whispering used to be in my personal GH repo, but I recently moved it as part of a larger project called Epicenter (https://github.com/epicenter-so/epicenter), which I should explain a bit... I’m basically obsessed with local-first open-source software. I think there should be an open-source, local-first version of every app, and I would like them all to work together. The idea of Epicenter is to store your data in a folder of plaintext and SQLite, and build a suite of interoperable, local-first tools on top of this shared memory. Everything is totally transparent, so you can trust it. Whispering is the first app in this effort. It’s not there yet regarding memory, but it’s getting there. I’ll probably write more about the bigger picture soon, but mainly I just want to make software and let it speak for itself (no pun intended in this case!), so this is my Show HN for now. I just finished college and was about to move back with my parents and work on this instead of getting a job…and then I somehow got into YC. So my current plan is to cover my living expenses and use the YC funding to support maintainers, our dependencies, and people working on their own open-source local-first projects. More on that soon. Would love your feedback, ideas, and roasts. If you would like to support the project, star it on GitHub here (https://github.com/epicenter-so/epicenter) and join the Discord here (https://go.epicenter.so/discord). Everything’s MIT licensed, so fork it, break it, ship your own version, copy whatever you want!