James Summerill

Career break & independent technical projects

Independent October 2024 — present County Durham, United Kingdom

Took a career break for personal reasons and continued independent development on selected projects: deployed developer tools, AI and agent infrastructure, and experimental systems research.

Selected independent work →

Ruby on Rails Engineer → Senior Back End Developer

City Electrical Factors October 2019 — October 2024 (contract, then full time) County Durham, United Kingdom

Maintained and evolved the primary cef.co.uk system — first on contracts that upgraded it off long-unsupported Rails versions, then full time owning cross-cutting technical health and helping steer engineering practice toward TDD, CI/CD and clearer domain boundaries.

The upgrade path, written up on the blog →

• Phase 1 · Rails 3.2 → 4.2, October 2019 — May 2020 (contract): upgraded a production retail application off a framework version that had been out of support for years, released in steps rather than as one cutover.
• Phase 2 · Rails 4.2 → 5.2, December 2020 — March 2021 (contract): the next hop, made smaller by having cleared the previous one's deprecations rather than deferring them.
• Phase 3 · March 2021 — October 2024 (full time): returned to own cross-cutting upgrades across Rails versions, gems and dependencies.
• Championed Docker containerisation and led the Bitbucket Pipelines implementation, so a green build meant a runnable environment.
• Built and maintained API integrations bridging modern applications and legacy Sybase systems.
• Advocated a modular-monolith direction using Packwerk and domain boundaries, without prematurely splitting the system into services.
• Promoted TDD and CI/CD, and shared approaches and emerging practices with the wider team.

Senior Developer / Lead Developer

clixifix January — October 2019 / May — October 2020 United Kingdom

Led and supported Ruby on Rails developers in a lean team, providing hands-on guidance, feedback and technical direction.

• Analysed the existing platform and documented recommendations, supporting continuity across development work.
• Contributed to hiring, collaborative working practices and iterative delivery.

Ruby on Rails Software Engineer

Imfuna October 2016 — February 2018 Remote

Maintained and extended the Rails platform and collaborated remotely with colleagues across functions.

• Worked with the Transcription Manager on an AI transcription service, reducing validation time for human reviewers and the cost of running it.

Earlier roles

Various June 2013 — December 2015 United Kingdom

Four roles across agencies and product companies, in Ruby and the web stacks of the time.

• Evvnt · Ruby Developer, April — December 2015: maintained the Ruby/Heroku website and infrastructure, and developed Ruby, Watir and Sidekiq automation that reduced manual work.
• Arnold Clark · Ruby / Web Developer, July 2014 — March 2015: worked across legacy systems and new features, including Worldpay, AWS, Rails and Swift, and built an internal office dashboard on Raspberry Pi, Dashing and Debian.
• Appkick · Lead Backend Engineer, February — November 2014: led backend development, migrated the core application from Node.js to Ruby, and introduced CI practices and improved remote-team delivery workflows.
• Green Gorilla Apps · Full Stack Web Developer, June 2013 — May 2014: maintained and extended existing web applications and fixed defects, following Git-based review practices.

Rails modular monolith with DDD Public repo

Packwerk boundaries, a transactional outbox and a Kafka consumer in Rails.

Webcap Live

Developer API for web capture, extraction and monitoring.

agents.shoutsid.fyi Live

A shared knowledge exchange for agents, where a claim is only verified when someone else reproduces it.

Planetary Matrix Public repo

A headless Earth-scale simulation core, partitioned into shards that do not share memory.