lol thank you IEEE for giving me a good laugh (CC @mweidner.bsky.social)

Fun academic find: the core idea of server reconciliation (a general approach to real-time collaboration that's simpler than Operational Transformation or CRDTs) already appears in an MIT tech report from 1985.

From the ~1st collaborative text editing paper: if two users do "delete char @ index 7" concurrently, no serial ordering gives the correct answer. So the authors abandon serializability, leading to OT/CRDTs. But if you rephrase the ops as "delete char @ <per-char id>", both serial orders work!

It took almost two years…! The Fugue paper that @mweidner.bsky.social and I wrote about interleaving in collaborative text editing algorithms was finally accepted by IEEE Transactions on Parallel and Distributed Systems paywalled: ieeexplore.ieee.org/document/111... free: arxiv.org/abs/2305.00583

The Art of the Fugue: Minimizing Interleaving in Collaborative Text Editing

Most existing algorithms for replicated lists, which are widely used in collaborative text editors, suffer from a problem: when two users concurrently insert text at the same position in the document,...

arxiv.org

I made a guest post on @powersync.com's blog: powersync.com/blog/collabo... It describes a demo we made of collaborative text editing on top of PowerSync's DB sync engine, using character IDs & totally-ordered updates in a DB table (w/o CRDTs).

Collaborative Text Editing Over PowerSync

This blog post describes the resulting demo of collaborative text editing over PowerSync. The demo uses Tiptap as the editor, has basic support for shared cursors and anonymous share links, and includ...

powersync.com

Watch @mweidner.bsky.social talk about collaborative text editing without CRDTs or OT. youtu.be/5CFrpd0sG-g?...

Matthew Weidner.mp4

Whether your app is local-first or more traditional, collaborative text editing is a tricky problem that requires advanced algorithms. Or does it? In this ta...

drive.google.com

"Collaborative text editing without CRDTs or OT" Awesome talk from @mweidner.bsky.social on how you don't need CRDTs to build collaborative text editing.

New blog post: "Collaborative Text Editing without CRDTs or OT". It describes what I hope is a simpler and more flexible approach to the hardest part of a collaborative app, text editing. mattweidner.com/2025/05/21/t...

I look forward to talking about some new ideas from my work at Common Curriculum & CMU!

Local-First Conf@localfirstconf.com · last yr.

We’re excited to announce that @mweidner.bsky.social PhD student at CMU, will be speaking at Local-First Conf 2025! Matthew will share a surprisingly simple approach to collaborative text editing—no CRDTs or OT required.

My most recent blog post (from last summer): Architectures for real-time collaborative apps using a central server. It includes classic CRDT/OT approaches, why those might be overkill, and a classification table for existing apps/tools. mattweidner.com/2024/06/04/s...