Florian Jacob

Putting solar panels on land used for biofuels would produce enough electricity for all cars and trucks to go electric The world dedicates a Poland-sized area of land to liquid biofuels. Is there a more efficient way to generate energy?

PV solar panels produce about 20x more usable energy per hectare of land than growing biofuels ourworldindata.org/biofuel-land...

Open Local First For the first time this year, the FOSDEM conference will host a devroom for Local First, CRDTs and sync protocols and sync engines. FOSDEM is the biggest Free and Open Source conference in Europe. Thi...

@patternist.xyz and I are talking about @automerge.org and Keyhive at @fosdem.org 2026 in the @localfirst.bsky.social room 🎉 If you're attending FOSDEM, come say hi!

openlocalfirst.org/schedules/#4...

LLM APIs are a Synchronization Problem Maybe the LLM message APIs should be rethought as a synchronization problem.

I am also gradually coming round to the view that interaction between humans/client apps and (perhaps multiple) AI agents is a state synchronisation problem that probably needs CRDTs lucumr.pocoo.org/2025/11/22/l...

Eventually Consistent Access Control: Practical Insights on Matrix from Decentralized Systems Theory Access control is the core of any system's security, but usually provided by a single, centralized server. However, access control in a M...

With our talk “Eventually Consistent Access Control: Practical Insights on Matrix from Decentralized Systems Theory”, we were at the @matrix.org conference 2025 in Strasbourg: media.ccc.de/v/matrix-con... [m]@🇫🇷🥳 The talk covers scientific foundations as well as 6 years of our own research on Matrix.

Pittsburgh at night

Our paper “To the Best of Knowledge and Belief: On Eventually Consistent Access Control” is now available as CC-BY: dl.acm.org/doi/10.1145/... At the example of
@matrix.org, we showed traditional conceptualizations of access control as insufficient, and present eventual consistency as alternative.

I am happy to hear that, monotonicity and what it means for decentralized systems was our main insight we hoped to bring across! 😃

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,...

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

Automerge Automerge is a library for building collaborative, local-first applications.

New Automerge website at automerge.org. Kudos to @spiralganglion.com and @seaofclouds.com for their work building it. The level of craft and detail in the landing page is very satisfying.

Proof-Carrying CRDTs allow Succinct Non-Interactive Byzantine Update Validation | Proceedings of the 12th Workshop on Principles and Practice of Consistency for Distributed Data

Our paper “Proof-Carrying CRDTs allow Succinct Non-Interactive Byzantine Update Validation” dl.acm.org/doi/10.1145/... is the first to combine CRDTs with non-interactive cryptographic proofs. They match very well, performance is good for non-critical tasks. Implementation: github.com/kit-dsn/proo...

Our newest paper, “ReP2P Matrix: Decentralized Relays to Improve Reliability and Performance of Peer-to-Peer Matrix”, is now available under CC-BY: dl.acm.org/doi/abs/10.1... Code and data based on the existing peer-to-peer @matrix.org prototypes available as well: gitlab.kit.edu/kit/tm/telem...

ROBUST 2025 Workshop @ KIT Karlsruhe, Germany — March 17 and 18, 2025 Resilient Operations - Byzantine Fault Tolerance and State-Machine Replication

My research group hosts this year's ROBUST 2025 workshop on Byzantine fault tolerance and state-machine replication, and seeks your participation and contributions! We look for 25min presentations, including preliminary results and open question. See you on March 17/18! gi-robust.github.io/robust25/

Florian Jacob - Matrix Conference 2024 Matrix Salon Podcast · Episode

I was guest in the new German episode of the #Matrix Salon Podcast, talking about my research on the (de)centralization of the Matrix server network and my journey to @matrix.org 😊

Episode: open.spotify.com/episode/34th...
RSS feed: anchor.fm/s/cdb34188/p...

Approaches to Conflict-free Replicated Data Types | ACM Computing Surveys Conflict-free Replicated Data Types (CRDTs) allow optimistic replication in a principled way. Different replicas can proceed independently, being available even under network partitions, and always co...

Here is an excellent and modern introduction to CRDTs. dl.acm.org/doi/10.1145/...

A yellow, empty Berlin subway train at an empty platform, doors open, everyone has already departed to Berlin central station.

The #MatrixConf has left Berlin 🇩🇪, for now. I love to scroll through the photos in the Matrix guest book everyone created together at the closing, the conference had such a nice vibe. 📸 See you all again in France, October 2025! 🇫🇷👋

Matrix conference logo sprayed on the floor, open portal to the conference venue in background.

The first ever #MatrixConf is going great, so many people, ranging from researchers to practitioners, companies to government organizations. 😄 First time I heard from the Matrix efforts of the Swiss post for a nationwide communication system, especially for B2C cfp.matrix.org/matrixconf20... 🇨🇭

🎉 I'm super excited to share the first post giving a high level overview of the local-first access control project that we're working on at Ink & Switch! 🐝✨ www.inkandswitch.com/beehive/note...

The latest Ink & Switch Dispatch features some projects dear to my heart: collaboration for research papers, and local-first access control for end-to-end encryption www.inkandswitch.com/newsletter/d...

Thanks! Have not stumbled over WNFS before - seems like hash chronicles for versioning that consists of IPFS-like MerkleDAGs for the file system? Very interesting - we had no example in the paper that combines both, would have been nice to explain the difference. 😀

Logical Clocks and Monotonicity for Byzantine-Tolerant Replicated Data Types | Proceedings of the 11th Workshop on Principles and Practice of Consistency for Distributed Data

Our newest paper, “Logical Clocks and Monotonicity for Byzantine-Tolerant Replicated Data Types”, is now available under CC-BY: dl.acm.org/doi/10.1145/... We formalize @matrix.org and other autonomous decentralized systems based on hash chronicles to verify monotonicity and Byzantine fault tolerance