Top Senior Software Engineer Jobs in Hartford, CT

Build and improve Mozilla’s Firefox Add-ons platform, including moderation pipelines, reviewer tools, DevHub, and full-stack features. Develop React/TypeScript frontends and Django/MySQL backends, improve reliability through Google Cloud deployments, monitoring, and incident response, and create observability and security systems. Collaborate with product, design, QA, reviewers, developers, and open-source contributors while responding to platform incidents and supporting ecosystem safety.

Build, enhance, modernize, test, deploy, and sustain enterprise Java and Spring Boot applications supporting DoD financial and program management. Responsibilities include full-lifecycle feature ownership, Oracle schema and SQL development, Angular contributions, CI/CD pipeline delivery, security scanning, defect investigation, architecture participation, code reviews, and secure cloud deployment. The role requires evaluating existing systems, applying sound technical judgment, and meeting federal security and compliance requirements.

Build and sustain enterprise Java applications for DoD financial and program management. Own capabilities across requirements, architecture, API development, database design, testing, CI/CD deployment, security, and production sustainment. Work across Spring Boot, Angular, Oracle, SQL, and cloud environments while investigating defects, reviewing code, using AI-assisted tools responsibly, and contributing to agile delivery. Seven or more years of software development experience, a technical bachelor’s degree or equivalent experience, Security+ certification, U.S. citizenship, and Secret clearance eligibility are required.

Own the architecture and development of data-intensive web applications powering customer insights. Provide hands-on technical leadership, mentor engineers, conduct architecture and code reviews, resolve complex distributed-system issues, and deliver performant, maintainable data products. The role involves ETL and/or RAG development, full-stack work across React, TypeScript, Next.js, PostgreSQL, and C#/.NET, with opportunities to operate cloud infrastructure and observability systems.

Build and own software for marina operators and boaters across reservations, payments, CRM, work orders, accounting integrations, and mobile applications. Responsibilities span scoping, design, implementation, deployment, maintenance, and improving a legacy system handling live payment traffic. The role requires full-stack development, AI-assisted engineering, product judgment, clear communication, and ownership of customer outcomes in a lean team.

Build and maintain scalable full-stack healthcare software in collaboration with clinicians, operators, and product managers. Own solutions from understanding business problems through delivery and measurement, make independent technical and product decisions, incorporate AI agents, and improve development practices through testing and documentation. The role involves developing and refactoring complex distributed systems while connecting engineering work to user and business outcomes.

Leads architecture, design, and hands-on development for scalable backend APIs and interoperability services. Sets engineering standards, drives cross-team technical initiatives, mentors engineers, reviews code and designs, manages technical risks, and partners with engineering leadership on roadmaps. The role focuses on distributed systems, authentication, cloud SaaS, API integrations, and standards such as FHIR, while contributing production code and fostering collaboration.

Lead architecture, development, and delivery of Azure SmartNIC and networking software, including RDMA, virtualization, hardware offloads, and high-performance networking. Collaborate across hardware, firmware, silicon, and cloud teams; improve reliability and performance using telemetry; guide platform strategy; troubleshoot production systems; and provide technical leadership through design reviews, mentoring, and incident response.

Lead the architecture and technical direction of Alpaca’s margin and risk systems across equities, options, crypto, and future asset classes. Design low-latency, high-throughput services for margin calculation, real-time risk enforcement, exposure limits, margin calls, and operational workflows. Drive reliability, correctness, transactional integrity, observability, incident prevention, technical reviews, mentorship, and cross-functional integration with product, brokerage operations, compliance, and engineering teams.

Design, build, and operate backend Go services and smart contracts that mint, burn, bridge, and reconcile wrapped assets across multiple chains. Own end-to-end delivery from smart contract deployment through API design, SLOs, and production rollout. Drive asset migration pipeline improvements, run on-call operations, build observability and runbooks, and mentor junior engineers.

Design and deliver blockchain network infrastructure and platform APIs, lead multi-quarter initiatives (chain integrations, re-architecture, data migrations), define APIs/SLOs/observability and on-call ownership, ship SDKs and platform primitives, establish data contracts, and simplify cross-chain operations to enable analytics, ML, and data engineering teams.

Design, build, and operate cloud-native, enterprise-grade SaaS services on Azure. Lead architecture and design, develop APIs and UIs, apply AI-enabled engineering tools, ensure observability, support production incidents, and drive reliability, performance, and CI/CD improvements across teams.

Build and scale Ruby on Rails backend systems powering StackBlitz and Bolt.new. Responsibilities include improving application scalability, reliability, and performance; optimizing PostgreSQL and object storage; developing platform features and integrations; supporting developer infrastructure; and reviewing code. The role works across Rails and Node.js/TypeScript stacks in a globally distributed, remote team.

Lead a developer productivity engineering team responsible for CI/CD, build systems, internal tooling, and AI-augmented development workflows. Improve developer experience, engineering velocity, and software quality through scalable infrastructure, productivity metrics, AI tool adoption, coaching, and governance. Partner cross-functionally, mentor engineers, evaluate AI technologies and costs, and establish standards for security, correctness, licensing, and data handling.

Own the enterprise test automation strategy, scale a Playwright and JavaScript framework, expand coverage across Salesforce, MuleSoft, D365, and reporting systems, and build scalable execution and reporting infrastructure. Design QA standards, metrics, and review processes while developing AI-powered agents with Cursor for performance testing, regression analysis, and defect triage. Partner with engineering, product, business, and AI platform teams to deliver governed, reusable quality tooling.

Designs, develops, and maintains complex distributed software systems. Writes high-quality code, leads design and code reviews, translates product requirements into scalable architectures, leads sprint delivery, collaborates with stakeholders, and mentors engineers. The role requires expertise in programming, databases, APIs, messaging, microservices, containerization, DevSecOps, and technical strategy.

Design, develop, and maintain complex distributed software systems. Write tested, high-quality code; translate product requirements into scalable designs; lead design, code, and sprint activities; collaborate with stakeholders; and mentor engineers. The role also drives technical strategy, resolves delivery impediments, and promotes secure, maintainable, and reusable engineering solutions.

Own and extend Aledade’s AI enablement platform, including the MCP Gateway, connector integrations, plugin marketplace, model gateway, observability, telemetry, and cost attribution. Build secure authentication and authorization flows, CI/CD and distribution tooling, evaluation harnesses, model routing, and agent collaboration features. Mentor engineers, document platform practices, run enablement sessions, triage requests, and support on-call operations for gateway and marketplace availability.

Build scalable full-stack software for a cloud-based bioprocessing platform connecting scientific workflows, cloud infrastructure, and laboratory hardware. Develop emulators and hardware-in-the-loop testing systems, establish verification and traceability practices for regulated environments, deliver Console platform features, collaborate across software, hardware, and scientific teams, and mentor engineers.

Lead architecture and development of scalable full-stack systems spanning web, mobile, backend, data, and partner integrations. Build React and TypeScript applications, Node.js services, APIs, and AWS-based distributed systems. Drive cloud-native DevOps, reliability, security, compliance, and AI-assisted engineering practices. Influence cross-team technical direction, establish shared standards, mentor engineers, and lead initiatives across frontend, backend, mobile, and data domains.

Design, build, and scale high-throughput, low-latency Go services powering blockchain RPC infrastructure. Architect distributed systems, own production delivery, improve uptime and latency, resolve complex production issues, and collaborate across Product, Infrastructure, and Developer Experience teams.

Design, build, and operate high-throughput blockchain infrastructure using Go and Rust. Own distributed systems end to end, including architecture, performance optimization, security, testing, deployment, observability, incident response, and reliability. Lead technical designs and code reviews, mentor engineers, debug complex production issues, and collaborate across Product, Infrastructure, Security, and Developer Experience teams.

Lead backend-focused software architecture and development across distributed systems, data ingestion, experimentation platforms, AI workflows, and product capabilities. Build primarily in Python while contributing to React and TypeScript frontend work. Translate ambiguous product needs into scalable production systems, guide technical direction, partner with product and data teams, mentor engineers, and improve engineering practices.

Leads full-stack software development across the Censis application stack, including design, coding, testing, deployment, production support, and defect resolution. Develops C#/.NET and Vue.js applications, REST APIs, and SQL Server solutions. Improves security, reliability, observability, and performance through automated testing, secure coding, root-cause analysis, and preventive engineering practices. Mentors developers, leads technical discussions, collaborates across Product, QA, DevOps, Security, and Support, and uses approved generative AI tools responsibly.

Develop and maintain high-performance web frontend applications and backend services for a collaborative XR platform. Lead complex cross-team projects, shape cloud and web architecture, optimize browser and XR headset performance, and translate business requirements into product features. The role requires expertise in JavaScript, React, TypeScript, browser performance, distributed systems, real-time communication, AWS, and Electron, with preferred experience in 3D web technologies, cloud-native architecture, databases, containers, game engines, CI/CD, and observability.