Contract Role: Senior Ember.js Engineer Outside IR35 Fully Remote

Location: Remote (UK) Duration: 2-3 months Start: 21st July 2025 Engagement: Outside IR35 5 Years ember experience required (Minimum requirement) The Opportunity A well-established financial services product business is looking for a Senior Ember.js Engineer to lead a critical upgrade project across its legacy Ember applications. These applications are part of a wider FX payments back-office platform, with components that have not been updated in several versions and are now reliant on unsupported versions of Ember.js and Node.js. This is a focused engineering engagement. You’ll work within a mono-repo ecosystem, modernising the codebase, resolving dependencies, and ensuring successful delivery of a clean, stable, and production-ready upgrade. What is Required. Working closely with internal engineering leadership and DevOps support, you will: Upgrade Ember.js from ~v3.20.5 to Ember 6.x (Octane) . Upgrade Node.js to v20 across all associated packages. Migrate and validate shared packages within a monorepo (Lerna/Yarn Workspaces). Run and maintain comprehensive test coverage (unit, integration, and UAT). Identify and deprecate outdated libraries and plugins. Optionally consolidate “common” and “domain-common” packages into a single repo (without impacting delivery timelines) Tech Stack: Frontend : Ember.js (Octane), Glimmer, Handlebars Tooling : Lerna, Yarn Workspaces, ESLint, Prettier Testing : QUnit, qunit-dom, ember-qunit CI/CD : AWS Amplify Auth : Keycloak (OAuth2 integration) Languages : TypeScript, JavaScript Misc : Ember Engines, Babel, Sass, ember-auto-import, ember-fetc Skill-Set Deep experience upgrading and maintaining Ember.js applications (ideally 3.x → 5.x/6.x). Solid grasp of Node.js environments and version migrations (especially v20). Familiarity with monorepo structures , including Lerna and Yarn Workspaces. Experience working with Ember Engines and component libraries. Strong testing mindset – you’ve worked with QUnit or equivalent test runners in Ember. Good communicator – able to work autonomously and update stakeholders clearly. Deliverables Technical Upgrade Plan Comprehensive Test Plan and Cases Clean builds and validated UAT release Post-upgrade performance and stability report

Location: East London, London, GB

Posted Date: 7/31/2025