Top Senior Software Engineer Jobs in St. Louis, MO

Build and maintain scalable, cloud-native APIs and core marketplace systems. Lead software architecture and testing discussions, collaborate across teams, and improve application reliability, performance, telemetry, and operational health. The role uses .NET Core and related technology stacks, front-end JavaScript frameworks, Kubernetes, AWS, PostgreSQL, OpenTelemetry, and AI development tools.

Build and operate MoonPay’s developer platform, including APIs, SDKs, embedded components, reference applications, and integration tooling. Design secure browser and mobile experiences, simplify payment and crypto workflows, and ensure reliable distributed transaction processing. Own developer interfaces, documentation, versioning, observability, and migration strategies while supporting authentication, identity, KYC, payment methods, and purchasing capabilities across web, iOS, and Android.

Build and operate Airbnb’s large-scale NewSQL storage platform on stateful Kubernetes. Responsibilities include database kernel performance, storage and query internals, replication, CDC, failover, migration tooling, observability, permissions, and service discovery. Engineers investigate production incidents, improve reliability and latency, contribute to open-source database systems, and collaborate across storage, SRE, ORM, and interface teams.

Design, build, and operate Airbnb’s large-scale change data capture and batch export platforms. Improve reliability, performance, and efficiency across multi-tenant data infrastructure, collaborate with partner teams and internal customers, contribute to platform architecture, and participate in on-call operations. The role requires hands-on development, testing, debugging, and ownership of complex distributed systems supporting critical business functions.

Build and evolve scalable full-stack systems for People Data Labs’ APIs, self-serve products, and customer success tools. Responsibilities include designing frontend and backend architecture, developing React and Python applications, ensuring data integrity, implementing reliable APIs, optimizing performance, operating production services, collaborating with stakeholders, writing technical designs, mentoring engineers, and improving development practices.

Lead the technical direction and architecture of the Foundations platform team, owning authentication, authorization, SSO, secrets management, tenancy, and core platform services. Design APIs, drive services through launch, make technical decisions, establish engineering standards, and mentor engineers without formal management authority. Partner with engineering and product leaders to align execution with priorities.

Design and build data infrastructure automation, observability, health tooling, dashboards, and system improvements for large-scale object storage platforms. Lead technical designs and feature rollouts across services, improve fleet stability and throughput, automate hardware lifecycle processes, and partner with on-call teams to reduce operational toil and incidents.

Build and operate the platform supporting Honeydew’s digital dermatology product. Responsibilities include migrating data infrastructure to RDS, strengthening AWS security and compliance, standardizing logging, developing AI-assisted vulnerability remediation workflows, creating infrastructure and automation, supporting feature teams, and reviewing code. The role requires backend service and API development, platform security, infrastructure as code, CI/CD, and strong data and architecture skills.

Design, develop, deploy, and maintain scalable backend services, APIs, and frontend applications. Own projects from architecture through monitoring, collaborate with product and design teams, participate in technical and code reviews, troubleshoot complex issues, and improve engineering practices. The role focuses on secure, reliable systems across cybersecurity, AI, and distributed systems while providing technical guidance to peers.

Develop, test, deploy, and support resilient software solutions for Root’s payments and billing product domain. Collaborate with engineers and stakeholders to understand customer problems, communicate technical work, improve code and processes, and resolve production incidents affecting customers. The role requires software engineering experience, Ruby on Rails or equivalent expertise, and familiarity with React or React Native.

Leads engineering for one or more product-domain teams, partnering with Engineering Managers, Product, Data Science, Analytics, and Insurance stakeholders. Responsibilities include setting technical strategy and roadmaps, coaching engineers, driving cross-team initiatives, contributing code, leading incident response and resiliency improvements, and establishing engineering standards. Requires strong Ruby on Rails expertise, Rust familiarity, software leadership experience, and excellent communication skills.

Build, maintain, and steward open source cloud-native software for defense environments. Responsibilities include designing and implementing features, reviewing code, managing releases, engaging open source communities, resolving technical ambiguity, documenting systems, making architecture decisions, improving security and interoperability, and mentoring engineers. The role requires strong Go development, Kubernetes and cloud architecture expertise, collaboration with contributors and users, and participation in ecosystem standards and projects.

Leads architecture, hands-on software development, deployment, and production issue resolution for strategic customer projects. Drives AI innovation, platform resiliency, security, observability, performance, and operational improvements. Partners with executives, engineering, product, and customer success teams to prioritize strategic programs, improve customer value, share technical best practices, and remove production blockers.

Develops high-quality software and AI-powered prototypes for national security missions. Responsibilities include architectural design, feature development, automated testing, backlog grooming, sprint execution, API and SDK development, integration debugging, and research involving LLMs, embeddings, and smaller trained models. The engineer independently leads focused efforts while collaborating with product and engineering teams, using modern DevSecOps and CI/CD practices.

Leads the design, development, and maintenance of complex backend software systems. Owns significant features end to end, makes architectural decisions, improves scalability and performance, ensures code quality, mentors engineers, and collaborates with cross-functional teams. Builds production-ready C# and .NET APIs within microservices and containerized environments, using cloud databases and services. Participates in code reviews, testing, debugging, and continuous improvement.

Design, develop, and maintain scalable full-stack web applications using TypeScript, Java, Node.js, HTML, CSS, and MS SQL in a microservices environment. Build AI-powered applications with LLMs, RAG pipelines, GenAI agents, vector databases, and AI services. Optimize performance, implement responsive user interfaces, troubleshoot systems, participate in code reviews, and collaborate with AI/ML engineers and cross-functional teams in a remote setting.

Own backend services from design through production support, solve ambiguous technical problems, improve reliability, build automation, and contribute to architecture and technical decisions. The role involves developing secure software in a regulated healthcare environment, debugging production issues, writing tests, mentoring engineers, and using modern cloud, deployment, observability, and AI-assisted development tools.

Develop coding tasks and reference solutions for evaluating AI systems. Build deterministic verifiers, test suites, scalable backend services, and APIs. Debug complex defects, assess code quality, refactor legacy implementations, optimize performance, and evaluate AI-generated technical reasoning. Document requirements and verification criteria while independently applying software engineering judgment across algorithms, system design, testing, and reliability.

Own the architecture and delivery of major backend services and long-term engineering initiatives. Design scalable, dependable transaction-heavy systems, write technical proposals, assess business impact, and collaborate with product teams. Use and validate AI coding tools, coach engineers, and contribute to the technical roadmap. The role requires expertise in Node.js, TypeScript, distributed systems, and message brokers, with remote work from the US or Canada.

Provides technical leadership for Azure SQL databases supporting a highly available Azure service. Responsibilities include database performance tuning, reliability and capacity planning, schema changes, data migrations, observability, incident response, root cause analysis, operational automation, and technical strategy. The role partners with software engineers, SREs, and architects to improve scalability, durability, cost efficiency, and long-term service reliability across teams.

Lead architecture and roadmap for Azure PostgreSQL systems; design and review scalable, maintainable database engine features (query processing, storage, transaction logging, recovery, versioning, IO, scale-out). Influence coding standards and run code reviews, write proof-of-concept or production code, contribute to open-source PostgreSQL/Linux, and participate in rotational on-call operations.

Leads architecture and development of scalable, dependable platform features from concept through release. Creates technical design proposals, evaluates business impacts, uses and validates AI-assisted code, coaches engineers, contributes to technical roadmaps, and partners with product teams to align engineering work with business needs.

Design, develop, and improve scalable software for an investment platform. Lead software development across the lifecycle, mentor junior engineers, solve complex technical problems, maintain code quality through testing and reviews, and recommend technology enhancements. The role is remote in the USA with four in-person retreats annually.

Leads the design, development, and delivery of complex software systems. Drives architectural decisions and technical strategy, mentors engineers, conducts code reviews, partners with product stakeholders, and improves system performance, scalability, security, and compliance. Owns technical initiatives from design through delivery while maintaining high engineering standards.

Build and scale full-stack financial product experiences for OnePay’s employer benefits platform. Lead technical design, establish architectural and coding standards, optimize systems for reliability, security, performance, and scalability, and make technical decisions balancing rapid delivery with sustainable solutions. Collaborate with product, design, and operations to deliver features across web, iOS, and Android using distributed systems, APIs, and modern frontend technologies.