Top Senior Software Engineer Jobs in Hartford, CT

The Sr./Principal Software Engineer will design and implement core capabilities for SingleStore's cloud platform, focusing on scalability and reliability, while mentoring other engineers and collaborating with cross-functional teams.

Lead development and improvement of Firefox's Gecko accessibility engine: write and test C++ code, debug multi-process/multi-threaded and OS-specific issues, collaborate with design and product teams, influence web accessibility standards, build infrastructure exposing the web platform to assistive technologies, and ensure memory and performance targets are met.

Work on Firefox accessibility by improving the Gecko accessibility engine: write and test C++ code, debug multi-process/multi-threaded and OS-specific issues, collaborate with designers and other browser teams, influence web accessibility standards, and build infrastructure to expose the web platform to assistive technologies.

Design and develop scalable backend systems for SaaS applications, mentor engineers, and lead projects while collaborating with cross-functional teams.

The Staff Software Engineer will lead the software development lifecycle focusing on observability, design high-scale distributed systems, and mentor team members while ensuring technical excellence.

Design, build, and maintain backend systems and APIs for the Wikidata Query Service. Improve reliability, observability, automation, and scalability; monitor production, respond to incidents, support migrations, and collaborate across SRE, data, and product teams.

Design and build prototypes, tools, and production-grade platform and infrastructure solutions. Research architectures, solve complex technical problems, integrate APIs, apply ML and AI-assisted tools, and ensure defensive application design and secure, scalable releases.

Hands-on technical leader designing and building scalable, cloud-native claims applications on AWS. Architect and implement Generative/Agentic AI (LLMs, RAG, agents), mentor engineers, drive DevOps and IaC (Terraform), and collaborate with cross-functional teams to deliver secure, maintainable enterprise software.

Lead design and delivery of scalable, secure software across full stack and cloud. Collaborate with product and architecture teams, mentor engineers, drive best practices, integrate AI-assisted tools, and participate in the full SDLC to ensure system stability and performance.

The Senior Software Engineer will design and build scalable data solutions, manage backend systems, and enhance performance leveraging Golang and Python. Responsibilities include optimizing ETL processes and collaborating with teams to meet evolving customer needs.

Design, build, and maintain scalable AWS-based platform infrastructure including EKS/Kubernetes and EC2. Improve developer tooling, CI/CD, secrets management, and observability (Datadog). Operate and troubleshoot Linux hosts, Docker containers, and Terraform/Ansible automation. Mentor teammates, collaborate cross-functionally, participate in on-call rotation, and maintain self-hosted GitLab CI/CD infrastructure to support Omada's digital health programs.

Lead technical ownership and hands-on engineering for the integration backbone of a financial SaaS platform. Modernize legacy integration processes into .NET services, design reliable REST and file-based connectors, optimize Oracle SQL/PL/SQL, improve observability, and drive cloud-native Azure patterns. Mentor engineers, enforce standards, and champion AI-first development to increase delivery velocity and operational quality across multiple production ecosystems.

Principal IC responsible for reliability, observability, and modernization of a .NET-based Platform Services portfolio on Azure. Own architecture, resilience patterns, shared libraries, and migration of legacy .NET services. Implement observability, event-driven messaging, and AI-first engineering practices while mentoring engineers and partnering with architecture teams.

Design, build, and operate cloud infrastructure and internal developer tooling to scale a production SaaS platform. Improve performance, scalability, and security, integrate observability, build AI-assisted automation, support production debugging and incidents, and participate in on-call rotations while enabling strong developer experience and documentation.

Design, build, and operate high-throughput distributed data pipelines and platform infrastructure. Own end-to-end systems from architecture to production, write production-grade Python, optimize SQL at scale, architect service contracts, mentor engineers, and instrument systems for observability.

Lead design and hands-on development of AWS-based serverless backend and IoT cloud services. Build Python Lambda microservices, REST APIs, telemetry pipelines, and secure AWS IoT Core device communication. Mentor engineers, define architecture patterns, ensure production readiness (monitoring, CI/CD, security), and guide cross-functional integrations and technical roadmaps.

Own platform feature and API development, integrations, and deployments. Design, build, and maintain backend-focused full-stack features, collaborate with product and design, perform code reviews, troubleshoot, and work with cloud infrastructure and CI/CD pipelines to scale the marketplace.

Develop, deploy, and maintain the UDS Registry and related tools (Pepr, Lula). Lead architecture and implementation, integrate with defense systems, participate in on-call rotation, contribute to open source, produce documentation, mentor engineers, and influence product direction with user-focused design.

Lead design and implement scalable backend systems using Node.js, build RESTful APIs, design SQL schemas, optimize performance, mentor engineers, deploy on Azure, and maintain CI/CD, security, and observability.

Lead design and operation of the Synapse Everywhere external API platform: define API surface and guarantees, translate product and clinical requirements into contracts, own reliability and on-call incident response, provide technical mentorship and code reviews, and design scalable, secure cloud-native solutions (k8s, LLMs) with strong developer experience.

Design, build, and optimize scalable real-time and batch data pipeline infrastructure. Develop backend features focused on reliability and performance, write well-tested code, review technical designs, and contribute to infrastructure across mobile, desktop, and server systems.

Design, build, and maintain scalable backend services in C#/.NET powering payment routing, connector management, and platform configuration. Build secure, observable APIs and high-volume transaction processing systems, collaborate across Product/AI/Engineering, mentor junior engineers, drive architecture and standards, and own full lifecycle from requirements to deployment.

Build, operate, and scale core data services and APIs to process, store, and deliver large-scale patient health records with low latency and high availability. Provide technical leadership, contribute to architecture and design, collaborate with product and engineering teams, and coach engineers.

Design, build, and maintain AWS-hosted backend services (Lambda, Fargate) using JavaScript/Node.js. Develop and monitor RESTful APIs, create CloudFormation IaC, manage S3 data, integrate with Salesforce (refactor LWC/Apex), collaborate with Product, and document deployments.

Lead delivery of high-complexity digital banking implementations: design and build Java Spring Boot microservices, REST APIs, cloud-native containerized deployments, data and DB migrations, event streaming, monitoring and performance optimization. Act as a customer-facing technical lead conducting code reviews, test strategies, and cross-functional coordination to resolve operational issues.