Hello!

I’m Dr. Martin Kleppmann. Briefly about myself:

• I am an Associate Professor at the University of Cambridge, working on local-first collaboration software and distributed systems security. I teach Concurrent and Distributed Systems and Cryptography and Protocol Engineering, and I'm one of the people behind the Automerge open source project.
• I was previously a research fellow in the Systems Research Group at TU Munich (2022–2023), and at the University of Cambridge (2015–2022). Before that I was a software engineer and startup founder: I co-founded Rapportive (acquired by LinkedIn in 2012) and Go Test It (acquired by Red Gate Software in 2009).
• In 2017 I published a book for O’Reilly, called Designing Data-Intensive Applications. It covers the architecture of a broad range of databases and distributed data processing systems, and it has thousands of five-star reviews on Amazon. A second edition co-authored with Chris Riccomini is due to appear in late 2025, and is now in early release.
• I have composed several musical works, including “Die Türme des Februar” (in German), a musical-dramatic adaptation of the book by Tonke Dragt, which premiered in 2007 with a cast of 150 people.
• If you have found my work useful, please support me on Patreon. The income from Patreon goes towards supporting my research collaborators. Thank you to my supporters!

Feel free to contact me.

Recent blog posts

Things I have written recently.

• 05 Jul 2024: Pudding: user discovery for anonymity networks
• 04 Jan 2024: 2023 year in review
• 12 Oct 2022: Verifying distributed systems with Isabelle/HOL
• 03 Jan 2022: Book Review: The Future of Fusion Energy
• 01 Sep 2021: Several podcast interviews
• Full archive

Highlights

Older articles that have remained popular.

• 02 Dec 2020: Using Bloom filters to efficiently synchronise hash graphs
• 18 Nov 2020: New courses on distributed systems and elliptic curve cryptography
• 29 Sep 2020: Writing a book: is it worth it?
• 18 Jan 2018: Should you put several event types in the same Kafka topic?
• 08 Feb 2016: How to do distributed locking
• 11 May 2015: Please stop calling databases CP or AP
• 04 Mar 2015: Turning the database inside-out with Apache Samza
• 25 Nov 2014: Hermitage: Testing the “I” in ACID
• 05 Dec 2012: Schema evolution in Avro, Protocol Buffers and Thrift
• 07 Mar 2011: Accounting for Computer Scientists
• 05 May 2010: Valuation caps on convertible notes, explained with graphs

Conference talks

Events where I will be speaking or have spoken:

• 02 Apr 2025 at 20th European Conference on Computer Systems (EuroSys)
• 31 Mar 2025 at 12th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC)
• 30 May 2024 at Local-First Conference
• 27 Feb 2024 at Local First (LoFi) meetup
• 06 Nov 2023 at IETF-118 Decentralization of the Internet Research Group
• Full archive
• YouTube playlist of my talks

Publications

Work-in-progress drafts:

• Matthew Weidner and Martin Kleppmann. The Art of the Fugue: Minimizing Interleaving in Collaborative Text Editing. Preprint arXiv:2305.00583, November 2023.

Books:

• Martin Kleppmann and Mitch Seymour. Secret Colors: A Gentle Introduction to Cryptography. Round Robin Publishing, April 2022.
• Martin Kleppmann. Designing Data-Intensive Applications. O’Reilly Media, March 2017.

Peer-reviewed papers in journals and top-tier conferences:

• Joseph Gentle and Martin Kleppmann. Collaborative Text Editing with Eg-walker: Better, Faster, Smaller. 20th European Conference on Computer Systems (EuroSys), April 2025. doi:10.1145/3689031.3696076 — Gilles Muller Best Artifact Award! :-)
• Ceren Kocaoğullar, Daniel Hugenroth, Martin Kleppmann, and Alastair R. Beresford. Pudding: Private User Discovery in Anonymity Networks. IEEE Symposium on Security and Privacy (S&P), May 2024. doi:10.1109/SP54263.2024.00167
• Geoffrey Litt, Sarah Lim, Martin Kleppmann, and Peter van Hardenberg. Peritext: A CRDT for Collaborative Rich Text Editing. Proceedings of the ACM on Human-Computer Interaction (PACMHCI), Volume 6, Issue CSCW2, Article 531, November 2022. doi:10.1145/3555644
• Matthew Weidner, Martin Kleppmann, Daniel Hugenroth, and Alastair R. Beresford. Key Agreement for Decentralized Secure Group Messaging with Strong Security Guarantees. ACM SIGSAC Conference on Computer and Communications Security (CCS), November 2021. doi:10.1145/3460120.3484542
• Martin Kleppmann, Dominic P. Mulligan, Victor B. F. Gomes, and Alastair R. Beresford. A highly-available move operation for replicated trees. IEEE Transactions on Parallel and Distributed Systems 33(7):1711–1724, October 2021. doi:10.1109/TPDS.2021.3118603
• Daniel Hugenroth, Martin Kleppmann, and Alastair R. Beresford. Rollercoaster: An Efficient Group-Multicast Scheme for Mix Networks. 30th USENIX Security Symposium, August 2021.
• Stephan A. Kollmann, Martin Kleppmann, and Alastair R. Beresford. Snapdoc: Authenticated snapshots with history privacy in peer-to-peer collaborative editing. Proceedings on Privacy Enhancing Technologies (PoPETS), Vol. 2019, Issue 3, July 2019. doi:10.2478/popets-2019-0044
• Victor B. F. Gomes, Martin Kleppmann, Dominic P. Mulligan, and Alastair R. Beresford. Verifying Strong Eventual Consistency in Distributed Systems. Proceedings of the ACM on Programming Languages (PACMPL), Vol. 1, OOPSLA, Article 109, October 2017. doi:10.1145/3133933 — Distinguished Paper Award and Distinguished Artifact Award! :-)
• Martin Kleppmann and Alastair R. Beresford. A Conflict-Free Replicated JSON Datatype. IEEE Transactions on Parallel and Distributed Systems 28(10):2733–2746, April 2017. doi:10.1109/TPDS.2017.2697382

Peer-reviewed papers in other conferences and workshops:

• Emilie Ma and Martin Kleppmann. Kintsugi: Decentralized E2EE Key Recovery. 29th International Workshop on Security Protocols, March 2025. — Best Presentation Award! :-)
• Martin Kleppmann, Paul Frazee, Jake Gold, Jay Graber, Daniel Holmgren, Devin Ivy, Jeromy Johnson, Bryan Newbold, and Jaz Volpert. Bluesky and the AT Protocol: Usable Decentralized Social Media. ACM CoNEXT-2024 Workshop on the Decentralization of the Internet (DIN), December 2024. doi:10.1145/3694809.3700740
• Jessica Man, Sadiq Jaffer, Patrick Ferris, Martin Kleppmann, and Anil Madhavapeddy. Emission Impossible: privacy-preserving carbon emissions claims. 1st International Workshop on Low Carbon Computing (LOCO), December 2024.
• Leo Stewen and Martin Kleppmann. Undo and Redo Support for Replicated Registers. 11th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), April 2024. doi:10.1145/3642976.3653029
• Liangrun Da and Martin Kleppmann. Extending JSON CRDTs with Move Operations. 11th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), April 2024. doi:10.1145/3642976.3653030
• Martin Kleppmann. Making CRDTs Byzantine Fault Tolerant. 9th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), April 2022. doi:10.1145/3517209.3524042
• Peter van Hardenberg and Martin Kleppmann. PushPin: Towards Production-Quality Peer-to-Peer Collaboration. 7th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), April 2020. doi:10.1145/3380787.3393683
• Martin Kleppmann. Moving Elements in List CRDTs. 7th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), April 2020. doi:10.1145/3380787.3393677
• Martin Kleppmann, Adam Wiggins, Peter van Hardenberg, and Mark McGranaghan. Local-first software: You own your data, in spite of the cloud. ACM SIGPLAN International Symposium on New Ideas, New Paradigms, and Reflections on Programming and Software (Onward! ’19), October 2019. doi:10.1145/3359591.3359737
• Diana A. Vasile, Martin Kleppmann, Daniel R. Thomas, and Alastair R. Beresford. Ghost trace on the wire? Using key evidence for informed decisions. 27th International Workshop on Security Protocols, April 2019. doi:10.1007/978-3-030-57043-9_23
• Martin Kleppmann, Victor B. F. Gomes, Dominic P. Mulligan, and Alastair R. Beresford. Interleaving anomalies in collaborative text editors. 6th Workshop on Principles and Practice of Consistency for Distributed Data (PaPoC), March 2019. doi:10.1145/3301419.3323972
• Martin Kleppmann, Stephan A. Kollmann, Diana A. Vasile and Alastair R. Beresford. From Secure Messaging to Secure Collaboration. 26th International Workshop on Security Protocols, March 2018. doi:10.1007/978-3-030-03251-7_21 — Best Presentation Award! :-)
• Martin Kleppmann and Conrad Irwin. Strengthening public key authentication against key theft. 9th International Conference on Passwords, December 2015. doi:10.1007/978-3-319-29938-9_9

Invited papers, book chapters, and unrefereed reports:

• Martin Kleppmann and Norbert Locher. Die Türme des Februar: Eine Musical-Adaption. In Helma van Lierop-Debrauwer and Jana Mikota (eds). „Ich bin eine Märchenerzählerin. So wurde ich geboren.“ Universitätsverlag Siegen, April 2023. doi:10.25819/ubsi/10415
• Karissa Rae McKelvey, Scott Jenson, Eileen Wagner, Blaine Cook, and Martin Kleppmann. Upwelling: Combining real-time collaboration with version control for writers. Ink & Switch, March 2023.
• Martin Kleppmann and Peter Alvaro. Research for Practice: Convergence. Communications of the ACM, volume 65, issue 11, pages 104–106, November 2022. doi:10.1145/3563901
• Martin Kleppmann. Assessing the understandability of a distributed algorithm by tweeting buggy pseudocode. University of Cambridge, Department of Computer Science and Technology, Technical Report UCAM-CL-TR-969, May 2022. doi:10.48456/tr-969
• Martin Kleppmann. Harm reduction for cryptographic backdoors. 14th Workshop on Hot Topics in Privacy Enhancing Technologies (HotPETs), July 2021.
• Martin Kleppmann. Thinking in Events: From Databases to Distributed Collaboration Software. Keynote at 15th ACM International Conference on Distributed and Event-based Systems (DEBS), July 2021. doi:10.1145/3465480.3467835
• Martin Kleppmann and Heidi Howard. Byzantine Eventual Consistency and the Fundamental Limits of Peer-to-Peer Databases. arXiv:2012.00472 [cs.DC], December 2020.
• Martin Kleppmann. Implementing Curve25519/X25519: A Tutorial on Elliptic Curve Cryptography. Draft manuscript, October 2020.
• Martin Kleppmann, Alastair R. Beresford, and Boerge Svingen. Online Event Processing: Achieving consistency where distributed transactions have failed. Communications of the ACM, Volume 62, Issue 5, pages 43-49, May 2019. doi:10.1145/3312527
• Martin Kleppmann, Victor B. F. Gomes, Dominic P. Mulligan, and Alastair R. Beresford. OpSets: Sequential Specifications for Replicated Datatypes (Extended Version). arXiv:1805.04263 [cs.DC], May 2018.
• Martin Kleppmann, Victor B. F. Gomes, Dominic P. Mulligan, and Alastair R. Beresford. OpSets: Sequential Specifications for Replicated Datatypes (Proof Document). Archive of Formal Proofs, May 2018.
• Martin Kleppmann. Apache Samza. In: Encyclopedia of Big Data Technologies, Springer, March 2018. doi:10.1007/978-3-319-63962-8_197-2
• Victor B. F. Gomes, Martin Kleppmann, Dominic P. Mulligan, and Alastair R. Beresford. A framework for establishing Strong Eventual Consistency for Conflict-free Replicated Datatypes. Archive of Formal Proofs, July 2017.
• Alastair R Beresford and Martin Kleppmann. Data Governance and Modern Computer Systems. British Academy and Royal Society workshop on the governance of data and its uses, July 2016.
• Martin Kleppmann. Making Sense of Stream Processing. O’Reilly Media, May 2016.
• Martin Kleppmann and Jay Kreps. Kafka, Samza and the Unix philosophy of distributed data. IEEE Data Engineering Bulletin 38(4):4–14, December 2015.
• Martin Kleppmann. A critique of the CAP theorem. arXiv:1509.05393 [cs.DC], September 2015.
• Martin Kleppmann. Simulation of colliding constrained rigid bodies. University of Cambridge, Computer Laboratory, Tech Report UCAM-CL-TR-683, April 2007. doi:10.48456/tr-683 — Prize for best undergraduate dissertation! :-)