Portrait of Lucia Pereira
Faculty · F · 04 · Faculty

Lucia Pereira

Cryptography engineer · independent · ex-Signal protocol team

Trust nothing. Verify everything. Read RFCs the way poets read poetry — with patience and underlinings.

At Lattice sinceCohort II · MMXXIV
Office hoursFri · 16:00 CET
Based inLisbon

Areas of practice.

A non-exhaustive list of what Lucia works on, has shipped, or has very strong opinions about.

cryptography TLS Signal protocol key exchange side channels constant-time code RFCs post-quantum secure messaging

Working on.

I spent six years on Signal's protocol team and wrote half a chapter of the public protocol audit. I left to consult independently — small engagements, mostly with companies who've discovered they have a crypto problem they didn't know they had.

I teach Cryptography & Security at Lattice. The first day of every cohort, I break a textbook protocol in front of the room, on the projector. It's the only way to convince people the textbook is genuinely a starting point, not the answer.

What students leave with is not a list of primitives — though they do learn those — but a kind of allergic reaction to magic. If you can't show me what's signing what, where the trust starts, and where the verification ends, I don't trust your design. By week six, neither do they.

We implement TLS 1.3 from RFC 8446. We break early SSL versions on purpose. We read about Spectre. By the end, students know how to read a security audit not just as a deliverable but as a piece of writing.

Currently on the desk.

What Lucia is reading or returning to. Many of these are assigned somewhere in the curriculum.

  • 01Cryptography Engineering · Ferguson, Schneier, Kohno2010
  • 02RFC 8446 — TLS 1.3 · IETF2018
  • 03Reflections on Trusting Trust · Thompson1984
  • 04Spectre Attacks: Exploiting Speculative Execution · Kocher et al.2019
  • 05Lessons from Attacks on Secure Hash Functions · Bellare et al.2017

Reserve a seat in
Cryptography & Security.

Lucia's Cryptography & Security course opens for Cohort XIII in January 2026. Twelve weeks, in residence in Berlin, capped at sixteen students.

Begin your application