James Chancellor
Senior Software Engineer
Brighton, UK
jameschancellor@gmail.com+44 7740 300198Download PDF

Senior software engineer building Java back ends and TypeScript/React full-stack products for large technology organisations and smaller product companies. Has independently taken mobile and web products from conception through design, cloud deployment, and launch. Experience includes complex algorithmic and modelling work, with recent independent work focused on AI agents and LLM-powered tools.

Experience
Selected Independent Software Projects
Sep 2025–Present
  • Created AI coding agent @jancellor/ask, with AGENTS.md and agent skills support, and resumable, branching sessions.
  • Built job-search tool with scraping, web UI and LLM skill extraction and role matching, retaining local data for analysis.
  • Developed supporting tools for AI-assisted development including local dictation and a Docker sandbox.
Bazaarvoice — Full-Stack Software Engineer — Contract via Toptal
Oct 2024–Apr 2025
  • Improved React statistics dashboard to include Instagram competitors.
  • Optimised YouTube creator search rankings using SciPy.
  • Designed ingestion pipeline for TikTok mentioned posts using Scala/SQS services.
FlintMint — Full-Stack TypeScript Engineer — Contract via Toptal
May 2023–Jan 2024
  • Developed TypeScript/Express APIs for clinical notes app including nested patient data model.
  • Implemented React interface for defining data structure schemas.
  • Added load balancing, TLS certificates, Cloud Run deployments and multi-environment support with Terraform and GitLab.
Aidium — Software Engineer — Contract via Toptal
Feb 2023–Mar 2023
  • Delivered integrations for TypeScript/GraphQL mortgage CRM.
  • Implemented Twilio call forwarding and Zapier app with webhooks for importing customer data.
Flux Vario — Independent Android App Developer
Apr 2022–Dec 2022
  • Independently designed, built and published Flux Vario, an Android flight instrument for paraglider pilots.
  • Engineered sensor-fusion algorithms for flight data including 3rd-order complementary filter measuring climb rate.
  • Designed low-latency audio pipeline for intuitive sonification of climb rate.
  • Combined Java sensor/audio code with React/JavaScript UI and Express/TypeScript/Docker/GCP back end.
Latch — Java Engineer — Contract via Toptal
Dec 2020–Sep 2021
  • Delivered core product features for Java/MongoDB API and Play web UI.
  • Introduced new automated API test suite, enabling faster and more confident development.
  • Integrated rapidly with third-party SOAP API, allowing onboarding of new clients ahead of schedule.
  • Improved performance by optimising algorithms, DB indexing and data formats, enabling onboarding of larger clients.
Ski Nav — Independent Mobile App Developer
Mar 2019–Apr 2020
  • Independently developed iOS/Android skiing app for point-to-point routing and locating friends in resorts worldwide.
  • Owned product end to end, including feature design, code, UX, graphics and app-store marketing.
  • Reached 5,000+ downloads within first few months of launch.
  • Engaged directly with users to set product direction and adapt to feedback.
  • Built Cordova/JS/Three.js client and Node/Koa API; deployed on AWS with Elastic Beanstalk, PostgreSQL, Redis and SNS.
Avian Hang Gliders — Independent Aerodynamic Modelling
Aug 2018–Oct 2018
  • Created hang glider model to investigate better handling/performance trade-off through low-tension, low-twist design.
  • Used Python/NumPy/SciPy to implement coupled finite element (structural) and vortex lattice (aerodynamic) system.
  • Implemented a nonlinear sail model capturing large deformations and wrinkling.
Genomics England — Java Engineer
Nov 2017–Apr 2018
  • Developed REST API features for Java/MongoDB knowledge base of clinical interpretations of genetic variants.
  • Established project's first automated test suite.
  • Built LDAP-based authentication service issuing JWTs.
Skiworld — Chalet Host / High Society & Off To Work — Events Assistant
Dec 2016–Sep 2017
  • Ran a ski chalet ranked 2nd of 14 for guest feedback.
Mendeley (Elsevier) — Java Engineer
Jan 2015–Dec 2016
  • Developed and maintained Java microservices with Dropwizard and MySQL on AWS.
  • Delivered features including OAuth authentication, Elasticsearch search, Hadoop pipeline orchestration and XML import.
  • Automated provisioning and configuration of build server infrastructure with Terraform and Puppet.
  • Mentored junior developers and developed technical interview questions.
Hotels.com (Expedia) — Java Engineer
Nov 2012–Sep 2014
  • Developed and maintained shared Java/Spring services, including core geographic data service.
  • Built systematic SQL process to identify and reconcile discrepancies during geographic data source migration.
Ocado — Java Engineer
Nov 2009–Oct 2011
  • Productionised 3D packing algorithm, assigning items to minimise containers, conveyor congestion and conflicts.
  • Ported PL/SQL 1D algorithm to Java as a fallback, greatly improving speed, while adding best-of-many randomised runs.
  • Led the second phase of development of system that directed staff from busier aisles to quieter ones.
Education
University of Bristol — MEng Mechanical Engineering
2004–2007
  • 2:1
University of Cambridge — Engineering
2003–2004
  • 85% overall exam result (chose to transfer)
Royal Grammar School, High Wycombe
1997–2003
  • A-levels: 4 A (96% average) — GCSEs: 13 A*/A