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

Location: Remote (UK)Duration: 2-3 monthsStart: 21st July 2025 Engagement: Outside IR355 Years ember experience required (Minimum requirement)The OpportunityA 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Workspaces).Run and maintain comprehensive test coverage (unit, integration, and UAT).Identify and deprecate outdated libraries and plugins.Optionally consolidate “common” and “domain-common” packages into a single repo (without impacting delivery timelines)Tech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, HandlebarsTooling: Lerna, Yarn Workspaces, ESLint, PrettierTesting: QUnit, qunit-dom, ember-qunitCI/CD: AWS AmplifyAuth: Keycloak (OAuth2 integration)Languages: TypeScript, JavaScriptMisc: Ember Engines, Babel, Sass, ember-auto-import, ember-fetcSkill-SetDeep 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. DeliverablesTechnical Upgrade PlanComprehensive Test Plan and CasesClean builds and validated UAT releasePost-upgrade performance and stability report

Created: 2025-08-03