01Oct 10, 2026
8 min readThe Hidden Costs of Shipping a Mobile App
Building a mobile app is getting easier every year. Turning it into a commercial product - especially from Spain, without a formal company - still has expensive, non-obvious walls.
Security · Systems · Engineeringtrustboundary.dev
TrustBoundary
Drawing the line between what you trust and what you must verify.
Security architecture, threat modeling, and systems thinking — by Álvaro Reyes.
01PrinciplesHow I think about the work
01Trust has edges
Every system has boundaries. Good security names them explicitly.
02Build, don't gatekeep
Automate the manual. Ship tooling teams actually use.
03Systems over stories
Competence shows in constraints and failure modes, not resume poetry.
02WritingLatest from the blog
02Sep 25, 2026
14 min readHow ML-KEM Works: From Noisy Equations to a Shared Secret
A walkthrough of FIPS 203: Module-LWE, the K-PKE building block, the Fujisaki-Okamoto transform, NTT multiplication, and why ML-KEM-768 is the default.
03Sep 24, 2026
7 min readPost-Quantum Crypto for Sysadmins: What You Actually Update
PQC is not a new TLS version. It is new key-exchange and signature algorithms inside your TLS stacks. Here is the mental model, what to inventory, and how to verify OpenSSL, Nginx, Java, and friends.
—The author
Álvaro Reyes
Security Engineer & Software Developer