Cyber Security Engineer and Linux systems engineer based in Zürich, Switzerland.

I build Linux systems, security tooling, and reproducible infrastructure. Current work is centered on NixOS, Rust, privacy-preserving systems, digital forensics, security architecture, and systems programming.

Plausibly deniable dual-environment computing for NixOS. Uses Linux OverlayFS together with the NixOS impermanence module to run a hidden environment alongside a visible decoy. Near-instant switching, with forensic artifacts minimized.

On-demand application availability for NixOS and Home Manager. Apps appear installed but download on first launch, keeping the host lighter.

Toward Plausibly Deniable Dual-Environment Computing (PDF)
MSc thesis, Stockholm University, 2026. The academic groundwork behind NAILS, with a forensic evaluation of what traces remain.

nixpkgs maintainer for the Portmaster application firewall: packaged it and wrote its NixOS module (NixOS/nixpkgs#442904).

Brave: Tor window fetched sidebar favicons outside Tor. Adding a page to the sidebar from a Tor window fetched its favicon from the real IP. Reported via HackerOne, fixed in Brave 1.96.60. Write-up

MSc in Information Security from Stockholm University.

8+ years working with Linux systems. 4 years in technical roles at ETH Zürich. Work across Linux systems, security engineering, reproducible infrastructure, digital forensics, and privacy-preserving systems.

Currently employed as a Cyber Security Engineer in Zürich.

Website: witteshadovv.dev · Notes
General: contact@witteshadovv.dev
Security: security@witteshadovv.dev · disclosure policy
HackerOne: witteshadovv
Keyoxide: profile
PGP: key (FCEB 73CE 73A7 00A8 8548 F25D CB4B BA75 1B7B 4D4D)
Signal: chat
Matrix: @whiteshadow332:matrix.org