Top Senior Javascript Jobs in Hartford, CT

Design, develop, test, debug, troubleshoot, and implement software components for intermediate-complexity systems. Participate in incident resolution, impact analysis, monitoring/alerting, and collaborate with the team to deliver steady, incremental releases.

Evaluate AI coding-agent interactions for usefulness, correctness, engineering judgment, explanation quality, and user trust. Provide rigorous, opinionated feedback distinguishing response quality levels and help define best practices for tools such as OpenAI Codex, Claude Code, and Cursor. This contract role requires experienced software engineering judgment rather than production coding.

Develop and maintain high-scale JavaScript and TypeScript monetization solutions using Prebid.js, Prebid Server, and Google Ad Manager. Own the header bidding wrapper, integrate auction and ad-tech standards, optimize Core Web Vitals and client-side performance, operate Google Cloud services, review code, document architecture, and resolve production issues.

Build end-to-end features in a JS/TS stack, designing scalable backend services and responsive real-time frontends. Improve observability, performance, and reliability, collaborate with product/design, and own full-stack implementation from APIs and data models to UI.

The role involves leading the development of a high-performance Web SDK for fraud detection and risk management, implementing algorithms for device fingerprinting, and ensuring security and performance optimization.

Develop and maintain rich Java-based and JavaScript-based user interfaces using modern UI frameworks. Implement component-based designs, integrate with middleware and RESTful services, work with WebSphere Portal/JSR286 and J2EE platforms. Collaborate across global teams in the insurance domain, perform technical design and programming, and apply analytical skills to deliver enterprise UI solutions.

Senior full‑stack engineer responsible for building backend services (Node.js/TypeScript) and integrating with frontends (React/Vue). Ship production APIs, collaborate cross‑functionally, own delivery, mentor peers, and develop modular, testable, performant systems across diverse greenfield projects.

The Senior Full Stack JavaScript Developer will build and maintain user interfaces using React and Next.js, integrate with Node.js backends, and guide other developers. Responsibilities include ensuring accessibility, performance, and reliability of features, engaging in code reviews, and collaborating closely with product teams.

Build and maintain Supabase JS/TS SDKs used across runtimes. Author libraries, manage public repos, triage issues, review PRs, keep CI/release automation healthy, own type experience, support realtime/WebSocket semantics, ensure cross-runtime compatibility, write RFCs, docs, and migration guides, and improve SDKs for AI coding agents.