Open to opportunities

Diarmaid O'Brien

@diarmaidobrien

Message

I build maintainable Android apps with Kotlin, Jetpack Compose, and clean architecture.

Ireland

Message

What I'm looking for

I'm currently seeking contract Android roles where I can modernize applications, build maintainable Kotlin features, improve stability, and support agile delivery.

At Teamwork.com, I modernized a legacy Android codebase with Jetpack Compose, Coroutines, and Flows while building messaging, help desk, and project-management tools used by 80,000+ active downloads.

I've led sprint delivery, production releases, pull request reviews, QA handoffs, and critical bug resolution, while mentoring junior developers and documenting code with KDoc. I also build Anyfin, a Jellyfin streaming client using Kotlin, Compose, ExoPlayer, MVVM, Hilt, and SQLDelight.

Experience

Work history, roles, and key accomplishments

Current

Anyfin - Jellyfin Client

Current

Personal Project

Nov 2023 - Present (2 years 9 months)

Developed a Jellyfin streaming client to explore modern Android technologies including Jetpack Compose, ExoPlayer (Media3), and Material3. Implemented MVVM architecture with Hilt and SQLDelight.

Kotlin Jetpack Compose ExoPlayer Media3 Material3 MVVM Hilt SQLDelight

Android Developer

Teamwork.com

Jan 2019 - Oct 2023 (4 years 9 months)

Spearheaded modernization of legacy architecture, migrating to Jetpack Compose, Coroutines, and Flows. Architected core features for business tools with 80,000+ active downloads, implemented testing strategies and CI/CD pipelines, and led technical delivery for multiple sprints.

Kotlin Jetpack Compose Coroutines Flow Hilt Junit MockK Bitrise CI CD Agile

Mobile Developer

Teamwork.com

Mar 2017 - Jan 2019 (1 year 10 months)

Managed maintenance and feature delivery of existing Appcelerator cross-platform applications. Designed and implemented key features from the ground up, collaborating with product managers to define technical specifications.

Appcelerator Cross Platform Development Debugging Crash Analysis Product Management

Education

Degrees, certifications, and relevant coursework

University College Cork

Bachelor of Science, Computer Science

2014 - 2018

Grade: First Class Honours

Activities and societies: College Scholar, Graduate of the Year Award nominee

Graduated with First Class Honours degree (77% overall). Nominated for Graduate of the Year Award 2018 and received the title of 'College Scholar' for results in 2nd, 3rd and 4th years.