Crypto Gloss

Peter Todd

Definition: Peter Todd is a Bitcoin Core developer and applied cryptographer known for proposing and implementing Replace-By-Fee (RBF), creating the OpenTimestamps protocol, and contributing extensive peer-reviewed cryptographic research to Bitcoin’s development. He is one of Bitcoin’s most technically rigorous and outspoken contributors.

Key Contributions

  • Proposed and championed Replace-By-Fee (RBF), which allows unconfirmed Bitcoin transactions to be replaced with higher-fee versions — now a standard Bitcoin feature
  • Created OpenTimestamps, an open standard for timestamping files and documents on the Bitcoin blockchain, widely used for provenance and audit trails
  • Authored numerous cryptographic proposals on the Bitcoin mailing list and in academic papers, including work on tree signatures, covenants, and commitments
  • Co-founded Coinkite (with others), though his primary role is as a researcher and developer
  • Actively debated scaling solutions including block size debates, firmly opposing simple hard fork increases in favor of layered solutions
  • Maintains a security consulting practice for crypto projects

Timeline

  • Pre-2012 — Software developer and participant in early Bitcoin forums.
  • 2012–2013 — Became one of the most active Bitcoin Core contributors. Began RBF discussions.
  • 2013 — Joined Viacoin as Chief Scientist briefly, then refocused on Bitcoin.
  • 2016 — RBF officially merged into Bitcoin Core and available as an opt-in feature.
  • 2016 — Created OpenTimestamps; launched opentimestamps.org.
  • 2017–2019 — Continued security research, protocol proposals, and public commenting on scaling debates.
  • 2020–2024 — Ongoing cryptographic research on Bitcoin privacy, covenants, and second-layer protocols.

Controversies

  • RBF controversy — Replace-by-fee was extremely controversial when proposed, with critics arguing it made zero-confirmation transactions insecure for point-of-sale payments. RBF advocates, including Todd, argued unconfirmed transactions were never secure. The debate continues in the Bitcoin community.
  • Block size wars stance — Todd was firmly in the “small block” camp during the 2015–2017 block size debates, opposing larger blocks in favor of off-chain scaling (Lightning Network).
  • Outspoken criticism — Todd is known for blunt, often controversial technical takes on crypto protocols, which some appreciate for directness and others find antagonistic.

Social Media Sentiment

Peter Todd is highly respected by Bitcoin developers and cypherpunks for his technical rigor. He is polarizing in broader crypto circles — admired for his intellectual honesty and criticized for dismissiveness toward alternative approaches. His OpenTimestamps work is almost universally praised as elegant and practically useful.

Last updated: 2026-04

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