39C3
The Critical Decentralisation Cluster (CDC) is returning to the 39th Chaos Communication Congress in Hamburg (Germany) during Dec 27-30 2025. We bring together assemblies and projects that challenge centralized infrastructures with decentralised, privacy-preserving and open hardware approaches. Expect talks, workshops and lots of hallway conversations around cypherpunk futures.
Planning for 39C3 is underway. Follow the links below to stay in the loop, propose sessions and coordinate with the cluster.
assemblies
- RIAT - independent research institute in Vienna
- Monero Community
- Namecoin - decentralized tamper-resistant naming system + PKI
- Swiss Cryptoeconomics
- I2P - fully encrypted peer-to-peer overlay network
- Cyberraum - hackers’ group from Hamburg
- Radicle - peer-to-peer code collaboration stack built on Git
- Social Dist0rtion Protocol - ad-hoc riddles and games
- GNU Boot - de-shittification for your BIOS and UEFI
- Department of Decentralisation - collective from Berlin
- Firo - independent blockchain privacy and decentralization tech research
- Iroh - library and protocol stacks to build next-gen P2P networks
- FOSSASIA - open-source community in Asia
- Off-Grid Messaging - independent networks over LoRa and packet-radio
- Ethereum Foundation - non-profit that supports the Ethereum ecosystem
- Sibermerdeka - hackerspace in Kuala Lumpur
- Replicant - fully free Android distribution
- Tropic Square - open-source IC designers
- Infinite Build - a peer-support group for builders
- Crypto Commons - P2P technologies for the stewardship of common goods
- BORDEL - hackerspace in Prague
- Gosling - P2P over Tor onion services
- Cat Pictures Data Distribution Hub - challenges with cute kitty pictures as rewards
contacts
- Coordination on Matrix: #cdc:dod.ngo — rooms bridge to hackint IRC
- Contact email: c3 at RIAT’s domain
- Submit proposals: pretalx.riat.at/39c3/cfp
More details on location, program highlights and collaboration spaces will land here as planning progresses. Reach out if your project aligns with decentralisation, privacy, cryptography or open hardware — see you in Hamburg!