@martin.kleppmann.com
Associate Professor at @cst.cam.ac.uk, researching decentralised systems and security protocols. Advisor to the Bluesky team. Wrote “Designing Data-Intensive Applications” (O’Reilly). he/him
@martin.kleppmann.comWe're probably going to collaborate with other people doing such formalisations rather than formalise a lot ourselves, but generally verification is something we're quite interested in!
@aria-research.bsky.socialReposted by @martin.kleppmann.comWith the capability to coordinate securely, AI agents could act reliably on our behalf, unlocking a whole range of interactions that were previously inaccessible.
Meet the first teams we’re backing to build the open-source tools to make it happen:
https://link.aria.org.uk/ST-Creators
@martin.kleppmann.comOur Centre for Cryptographic Trust Infrastructure (CCTI) is among the funded projects!
@martin.kleppmann.comWe just announced a big grant we got from @aria-research.bsky.social! We're aiming to use cryptographic protocols to allow mutually untrusting parties and their agents to prove to each other that they are telling the truth martin.kleppmann.com/2026/10/07/c...
@martin.kleppmann.comThis is a post about github.com/openai/math – theorems are free now, I guess
@martin.kleppmann.comAt first she believed her discovery was going to make her rich and famous. But soon everybody was making diamonds at home. What had once been scarce became abundant. The price of diamonds fell to zero, and nobody wanted them for jewellery any more. Soon, only the manufacturers of drill bits cared.
@martin.kleppmann.com"This is physically impossible!" she said, but a laboratory confirmed it: she really had created pure diamond from one of the world's most abundant minerals. Nobody understood why, but the method worked reliably. Anybody could now cheaply make diamonds at home in their kitchen.
@martin.kleppmann.comThere once was an old lady who had spent her entire life prospecting for diamonds, with little success. Then, one day during her retirement, she made a discovery: a home microwave oven, with the right settings, could turn quartz into diamond!
@jaz.shReposted by @martin.kleppmann.comHi protocol friends! I've been cooking up a Very Large PDS (vlpds) implementation capable of scaling up to billions of accounts and down to just one. It uses Object Storage as its only state, supports HA operation, live scaling up and down, is feature-complete with the reference PDS, and is FOSS.
@martin.kleppmann.comSo happy to see this! Thank you for serving on the board!
@martin.kleppmann.comOh yes, I had seen that before, but thanks for the reminder! The details are here: github.com/dunhamsteve/...
@martin.kleppmann.comIndeed! Great to see CRDTs so mainstream now. My wish is that @obsidian.md implements CRDTs next, since their current merging of edits from different devices is rather unreliable 😄
@martin.kleppmann.comTurns out that having an API of functions that only take a string as argument, and return another string, is really useful if you want to call it across the JavaScript/Wasm boundary
@martin.kleppmann.comNotion wrote a nice blog post on how they use CRDTs, including our Peritext algorithm for rich text! This must be one of the largest CRDT deployments out there? www.notion.com/en-gb/blog/h...
@martin.kleppmann.comNow even featured on TV! 😍 www.youtube.com/watch?v=Ktby...
@martin.kleppmann.comA researcher I'm working with in Cambridge, @zazbrown.com, just used AI and Lean to prove the Affine Plank Conjecture, an open problem for the last 75 years! (To be precise, he proved a special case not proven before; the general conjecture is still open.) zazbrown.com/research/pap...
@martin.kleppmann.comI only just found this post by @joehellerstein.bsky.social from February on how waiting, ordering, and commitment in distributed systems are all ways of looking at the same underlying idea: coordination. Good post, matches with how I think about it jhellerstein.github.io/blog/three-s...
@martin.kleppmann.comOk, so in general you end up building a tree? That seems like it should work. On your image there may be a typo though: on the right-hand blue arrow, should the second occurrence of “A2:A1” be “A2:A3”?
@martin.kleppmann.comHow do you handle the case of concurrent insertions at the same positions being assigned the same fractional index? Just appending a clientID to sort them seems to fall down when you subsequently insert between two chars with the same fractional index — what index do you pick then?
@martin.kleppmann.comThe $5,000 put in by the founders counts as capital too
