Top Senior Software Engineer Jobs in St. Louis, MO

Improve performance and scalability of web applications by identifying and resolving front-end and back-end bottlenecks. Optimize load times, API responses, and database queries; develop scalable features across the stack, monitor performance, conduct code reviews, troubleshoot production issues, and collaborate with product, design, and engineering teams.

Design, build, and maintain scalable full‑stack systems and APIs. Extend products to handle large datasets, reporting, and third‑party/Microsoft Graph integrations. Write secure, testable production code, participate in code reviews, troubleshoot performance issues, and mentor engineers. Own features end‑to‑end from design through deployment using CI/CD and DevOps practices in a distributed team.

Lead design, build, and operate scalable backend services and carrier integrations. Provide technical leadership, mentor engineers, drive architecture and best practices, write and test code, troubleshoot production incidents, and improve monitoring and reliability while collaborating with product and cross-functional teams.

Lead technical delivery of Enterprise Content Management (ECM) solutions, guiding design, development, integrations, CI/CD, automated testing, and cloud modernization. Provide hands-on .NET development, incident resolution, operational readiness, and coach engineering teams while ensuring security, retention, and governance for content services.

Lead implementation of software safety programs for underwater robotic/autonomous vehicles per MIL-STD-882. Produce safety plans and assessments, perform hazard analyses, track coverage metrics, catalog safety artifacts, review software independently, and present findings at reviews and customer meetings. Coordinate across programs and support demanding schedules with occasional travel.

Lead design and implementation of Pinterest Edge systems (CDN, TLS, DNS, proxies) to manage automation traffic and rate limiting at scale. Develop request-processing logic in Envoy, collaborate with vendors and platform teams, mentor engineers, use AI to accelerate workflows, and participate in on-call incident response and reliability improvements.

Design, build, and operate secure, scalable cloud infrastructure and platform capabilities. Implement IaC, improve CI/CD, observability, and automation. Lead incident response, reliability, and DevSecOps practices. Mentor engineers, drive platform standardization, document runbooks, and participate in a 24/7 on-call rotation to support production systems and remediation of systemic infrastructure issues.

Design and implement scalable, secure cloud-native microservices and data platforms. Collaborate with product and stakeholders, mentor junior engineers, build CI/CD pipelines, and translate business needs into developer-ready stories.

Design, build, and maintain scalable full-stack web applications. Implement backend APIs and responsive frontends, deploy to cloud, ensure security/performance, write tests, debug issues, participate in reviews, and mentor junior developers.

Hands-on senior full-stack engineer building and supporting user-facing features, infrastructure, and AI-powered workflows (LLM integration, RAG, agents). Drive architecture, dev experience, CI/CD, and partner with product and program teams to deliver a scalable education platform.

Design, build, and maintain large-scale, resilient systems; develop features and automated tests; mentor engineers; implement CI/CD and cloud-native infrastructure; integrate AI tools; lead projects, code reviews, and cross-team initiatives while improving engineering practices and documentation.

Build and maintain test automation, performance testing and analysis tooling for a distributed database (primarily in Python). Collaborate with stakeholders to create reproducible tests, extend developer tooling, and produce documentation and runbooks for maintainers and developers.

Lead backend architecture and system design for an AI-driven manufacturing planning platform. Build and scale a Node.js/Python stack with Azure Databricks, implement optimization and scheduling algorithms, establish engineering patterns, and mentor/lead a small early-stage engineering team while collaborating with product and data functions.

Lead design and delivery of platform capabilities that power a Federated GraphQL API and event-driven systems. Build and optimize gRPC endpoints, GraphQL APIs, and SQL for scale; own observability (DataDog, Bugsnag), mentor engineers, drive integrations, improve performance and reliability, and support customer-facing product teams across the organization.

The role involves building decision science libraries and tools for mineral exploration, collaborating with teams to improve decision-making processes.

Lead platform reliability: define SLOs/error budgets, own observability and deploy pipelines, harden integrations with dental systems, operate LLM-driven workflows safely, build incident practices, and raise engineering reliability across the company.

Architect, implement, and optimize cloud-based solutions; mentor junior engineers; design and deploy automated, production-grade systems; monitor cloud health and resolve incidents; apply cloud security best practices and healthcare compliance to ensure reliable, scalable infrastructure.

Design, build, and operate core platform infrastructure for an Agentic AI platform. Collaborate with cross-functional and ML teams to enable scalable, high-performance systems, provide production support and troubleshooting, and drive platform features that serve multiple products and engineering teams.

Design, develop, and maintain core platform infrastructure for an Agentic AI product. Lead foundational components, collaborate with cross-functional and ML teams, support production systems, troubleshoot performance and scalability, and cultivate developer-friendly frameworks and practices to enable large-scale distributed, AI-oriented workloads.

Build and operate the internal Developer Platform: improve monorepo CI/CD, scale agentic AI platform (observability, RAG, context engineering), consolidate build systems, automate developer toil, and drive DORA-aligned delivery across teams through design, code reviews, and platform roadmaps.

Design and build backend services and core user experiences for banks and customers. Implement REST APIs, integrate third-party services (Plaid, SendGrid), apply domain-driven design and microservices, perform system design, code reviews, and mentor teammates.

Lead design and implementation of gameplay and engine systems on Linux platforms. Mentor engineers, define technical specs, manage Linux infrastructure, optimize performance and security, integrate art, maintain documentation, support live services and mobile (iOS/Android) ports, and coordinate cross-team standards and tooling.

Lead development and maintenance of internal design system libraries, tools, and Figma plugins. Implement AI solutions to speed design workflows, own medium-to-large features end-to-end, run internal user research, provide support and on-call coverage, conduct design and code reviews, and collaborate with designers and engineers to drive technical strategy and adoption.

Remote Senior Software Engineer who evaluates Microsoft and complementary technologies, designs and implements custom software (C#, JavaScript, SQL), applies cloud and DevOps practices (Azure/AWS, CI/CD, containers), mentors and networks professionally, and continuously learns and advises clients.

Lead technical direction for the Growth team at Sanity.io, focusing on scalable solutions, mentoring engineers, and making data-informed architectural decisions.