Resume

Resume

Costa Fotiadis

Bristol, UK · costafotiadis@proton.me · linkedin.com/in/costafotiadis · github.com/CostaFot · costafotiadis.com

Senior Android Engineer with 12+ years building Android apps — the last 7 on Just Eat Takeaway.com's consumer app (10M+ MAU), where I co-author the company's cross-app Compose design system and own much of its platform tooling. Specialising in platform engineering, developer experience, and early adoption of new Android capabilities; technical writing featured in Android Weekly and platform work featured at Google I/O.

Work Experience

Senior Android Engineer — Just Eat Takeaway.com

Jan 2022 – Present · Bristol, UK
Android Platform & Experience team — consumer app, 10M+ MAU

Kotlin monorepo of millions of lines and hundreds of modules, shipping 16 branded apps to Google Play.

  • Co-author and maintainer of PIE, JET's Compose-first design system (its internal Material equivalent) — a full component suite driving hundreds of screens across the consumer, courier, and restaurant order-pad apps, giving ~100 Android engineers ready-made UI to ship faster.
  • Led JET's early adoption of Android 16 Live Updates for live order tracking — securing pre-release platform access from Google, reporting platform bugs directly to their engineers, and shipping at GA across an 88-ticket workstream. Drove a 22% increase in post-order screen views, a 2% reduction in support-contact propensity, and thousands of additional order reviews (42% of users keep the notification active through the full order).
  • Single-handedly migrated the monorepo's dependency injection to Dagger Hilt (30+ tickets, 40+ PRs across every feature domain) — deleting thousands of lines of boilerplate, letting any screen be built as an independent component, and unblocking the app's navigation rework.
  • Delivered the single-activity architecture and adaptive navigation (bottom bar, rail, and drawer) across the app's top-level screens — unifying deep linking, enabling Android 15 predictive back, and modernising transitions.
  • Shipped a complete rebrand of the consumer app in Jetpack Compose (2022) within a release cycle or two — my second full rebrand of the app (see previous role).
  • Drove the modularisation of the monorepo into hundreds of Gradle modules with affected-module CI — later restructuring it to cut full builds from 90+ minutes to under 45 (sub-30 for most changes) and hold cold start under 1s, as the Android team scaled from 12 to ~50 engineers.
  • Own CI through two platform migrations — TeamCity → Jenkins → GitHub Actions — running thousands of unit and UI tests (Firebase Test Lab) plus thousands of Roborazzi screenshot tests on every PR; fixed systemic test flakiness to cut Firebase Test Lab spend 45% (≈$10.2K → $5.6K/month).
  • Own the monorepo's code-quality gates — 15+ custom detekt rules, Android Lint on CI, SonarQube coverage enforcement (60% minimum), and CI autoformatting that raises fix-up PRs automatically — deterministic checks that eliminate nitpick review comments across ~50 engineers.
  • Serve on the release-manager rota for the bi-weekly release train (~20–30% of my time) — averted a Google Play takedown by driving an urgent PayPal/Braintree SDK upgrade with the vendor, and halted staged rollouts early (wakelock and ANR regressions) before they reached users.
  • Keep production healthy through extensive logging, automated alerts, and PagerDuty on-call — e.g. diagnosing a Firebase Analytics regression that was silently degrading targeting for €70–100K/day of UK ad spend.
  • Core interviewer for the Android hiring pipeline — ~20 technical interviews a year since 2023, trained 5 engineers to run the loop, and provided structured feedback that helped hire 15 Android engineers across consumer and ventures teams.

Android Engineer — Just Eat

Jan 2019 – Dec 2021 · Bristol, UK
Same team — promoted to Senior Android Engineer, Jan 2022

  • Delivered the 2020 rebrand of the consumer app end-to-end on the legacy View-based UI, plus Guest Checkout — both shipped on tight deadlines with no release slips.
  • Halved app cold-start time (to ~465ms) and eliminated the app's major ANRs; also fixed a years-old top crash in the internal logging pipeline.
  • Built the country-switching foundations and globalised core modules (address book, settings) that underpinned JET's later consolidation into a single global app.
  • First engineer to integrate the PIE design system across the app, mentoring the chapter through the migration.
  • Overhauled observability — Firebase custom keys, screen-tagged Kibana logs — and personally surfaced 8+ production incidents, including a silent 20% failure rate on the reviews endpoint. Rated "Exceptional" in 2020.

Android Developer — i-neda Ltd

Sep 2017 – Jan 2019 · Farnborough, UK
Pari-mutuel (tote) wagering systems for horse racing

  • Built an Android kiosk application used by staff at UK horse-racing tracks to accept tote bets, integrating with i-neda's OpenTote/MicroTote wagering platforms.
  • Developed reactive real-time betting flows with RxJava, optimised for dedicated low-spec Android terminal hardware.

Independent Developer — Google Play & Microsoft Store

2013 – Present

  • Began as a self-taught indie developer, self-publishing my own apps on Google Play (Anime Soundboard, Plenty of Cats, and others) — still maintained as a testbed for new tech.
  • Currently self-publish two open-source C#/.NET WinUI apps on the Microsoft Store — ADB Extension (Android device management) and Markets Extension (market tracking) for PowerToys Command Palette — owning the full lifecycle solo, from design and development to packaging and store distribution.

Education

  • Physics (undergraduate studies), University of Athens, Greece.

Technologies and Languages

  • Languages: Kotlin, Java
  • Android: Jetpack Compose, Coroutines & Flow, Dagger Hilt, RxJava, WorkManager, MVVM/ViewModel, SavedState & process-death handling
  • Quality & CI: GitHub Actions (previously Jenkins, TeamCity), Firebase Test Lab, Roborazzi, detekt & Android Lint (custom rules), SonarQube, Gradle modularisation, feature flags & staged rollouts, Datadog/Kibana observability
  • Beyond Android: Myriads of web frameworks, Kotlin Multiplatform, C#/.NET WinUI 3, PowerToys Command Palette extensions, Chrome extensions.

Writing and Recognition

  • Semi regularly featured in Android Weekly, e.g. "Injecting Composables with Dagger without losing it" featured in Android Weekly #624 (2024).
  • Android 16 Live Updates work at JET featured at Google I/O and shared by Google's official Android Developers channels (2025).
  • 25+ technical articles since 2020 on costafotiadis.com and the JET engineering blog — Jetpack Compose internals, Dagger/Hilt, static analysis, Kotlin Multiplatform.

Other

  • Earlier career in retail (UK & Greece, 2006–2011); national service, Greek Army (2011–2012).