Work
Security engineering for mobile systems that need reliable decisions under pressure.
This page outlines how I support teams shipping security-sensitive mobile and backend features. The focus is practical: clarify trust boundaries, remove unverifiable assumptions, and deliver implementation guidance that can be reviewed and deployed without hand-waving.
Mobile Security Architecture
Designing trust boundaries for iOS and Android clients where device state is untrusted, then defining server-verifiable evidence paths for high-risk decisions.
Backend Verification and Risk Controls
Building nonce, replay, and freshness checks into APIs so backend decisions remain defensible when client telemetry is incomplete or tampered.
Adversarial Testing and Failure Modeling
Running instrumentation-aware test scenarios, documenting bypass paths, and turning ambiguous failures into explicit policy outcomes.
Operational Readiness
Shipping traces, logs, and release checks that let teams see trust decisions in production and debug regressions without guesswork.
Working Style
- I start with boundaries and the failure modes that matter.
- I assume hostile clients where the system depends on untrusted claims.
- I prefer implementation realism over generic best-practice language.
- I care about clarity, observability, and maintainability under load.
- I usually test the unhappy path first so the rollout risk is obvious.
Common Deliverables
- Threat model and trust-boundary map for the target flow
- Server-side verification checklist with explicit acceptance/rejection states
- Implementation notes and code-level hardening recommendations
- Validation plan with replay, stale-token, and degraded-signal cases
- Rollout and observability guidance tied to measurable outcomes
Technical Coverage
Swift · Objective-C (legacy) · Python · JavaScript
SwiftUI · UIKit · Swift Concurrency (async/await) · XCTest-based unit testing · Performance profiling
iOS Secure Enclave · Biometrics (Face ID / Touch ID) · NFC · BLE
AWS · RESTful APIs · SQL · TLS
Bitrise · AWS CloudWatch · Structured Logging
Next Step
If you are planning a launch, incident hardening pass, or architecture review, share current constraints and risk tolerance. I can help define scope and sequence before implementation starts.