Top Senior Software Engineer Jobs in St. Louis, MO

Develop and maintain enterprise full-stack applications using Java Spring Boot, REST APIs, modern front-end frameworks, Oracle Exadata, and OpenShift/Kubernetes. Responsibilities include legacy code analysis, full-lifecycle development and testing, SQL and PL/SQL optimization, microservices deployment, CI/CD, code reviews, architecture discussions, monitoring, and Agile collaboration. The role requires an active transferable IRS MBI moderate-risk public trust investigation, U.S. citizenship, and substantial full-stack and cloud-native development experience.

Owns maintenance and support of Virscidian’s existing software products. Responsibilities include resolving defects and customer issues, developing C#/.NET desktop and server applications, working with SQL Server and REST APIs, supporting Azure resources and DevOps processes, troubleshooting deployments, and delivering incremental features. The role collaborates with support, product, business, and engineering teams while contributing to SaaS, scientific algorithms, performance, and scalability initiatives when appropriate.

Build and own Android growth and monetization experiments across subscriptions, pricing, advertising, purchases, and upgrade flows. Partner with product, design, data science, and analytics to instrument experiments, manage staged rollouts, monitor performance, and act on results. Use AI tools throughout development, contribute to Android architecture and engineering practices, participate in on-call support, mentor engineers, and help scale reliable mobile experiences to tens of millions of users.

Design, develop, and maintain scalable billing and invoicing systems using C# and PHP. Lead architecture, code reviews, mentoring, CI/CD improvements, monitoring, database optimization, security, and PCI DSS compliance. Use Claude and Cursor in daily development while validating generated code for correctness, security, performance, and maintainability. Collaborate across Product, Engineering, QA, and support teams to deliver reliable payment-processing services and resolve complex technical issues.

Leads technical direction and cross-team delivery of scalable software capabilities for a digital banking platform. Designs secure APIs, microservices, integrations, data contracts, and reliable full-stack systems. Partners across product, design, security, architecture, data, and engineering; mentors engineers; leads incident response; improves testing, CI/CD, developer tooling, and operational readiness. The role requires hands-on coding, architecture leadership, dependency management, and influence without direct people management.

Designs, develops, configures, and supports Edifecs healthcare EDI solutions and transaction mappings. Works with 837, 834, 835, 820, and 270/271 transactions; troubleshoots transmissions, configures validations, and develops Groovy scripts. Leads Agile and DevOps efforts, mentors engineers, supports QA, and designs scalable AWS applications using containers, microservices, and CI/CD. Provides technical leadership, architecture guidance, performance tuning, and stakeholder consultation.

Leads the architecture, development, testing, deployment, troubleshooting, and sustainment of Appian applications supporting Army systems. Provides technical leadership, code reviews, mentorship, secure coding enforcement, requirements collaboration, Agile participation, integrations, documentation, and compliance with DoD cybersecurity, RMF, STIG, and privileged-access requirements.

Build and improve scalable, accessible Android applications for Wikipedia and Wikimedia users worldwide. Responsibilities include leading technical discovery and system design, implementing Kotlin and Jetpack Compose features, optimizing performance, developing testing and observability practices, managing delivery risks and scope, and collaborating with product, design, analytics, and engineering teams.

Lead software engineering for the Patient Onboarding team, building and improving registration, insurance verification, and care-access workflows. Write full-stack production code, lead complex cross-team initiatives, shape technical direction, improve engineering foundations, and support modern AI-enabled development practices. Collaborate with Product, Design, Analytics, and Engineering to improve patient conversion and system reliability.

Develop and release Esri software for GIS, photogrammetry, remote sensing, defense, and intelligence workflows. Build high-performance image processing capabilities, algorithms, APIs, cloud-friendly desktop and enterprise applications, and support multiple imagery modalities and data formats. Collaborate with developers and product engineers to integrate libraries into ArcGIS, solve complex application-design problems, and mentor junior developers.

Develop and maintain software using C#, .NET, web technologies, SQL Server, and AWS. Participate in the full SDLC and Agile Scrum processes, including design, development, unit testing, defect resolution, backlog refinement, and collaboration with product and QA teams. Build solutions using Microsoft-stack technologies, optimize databases and stored procedures, and support cloud-based application delivery.

Build and scale data pipelines and partner integrations for an end-of-life open-source software dataset. Responsibilities include improving data quality, designing configurable risk-scoring models, integrating Kafka and data lakes, automating package generation and publishing, implementing monitoring and CI/CD, and documenting systems. The role also involves technical design, code reviews, mentoring, and collaboration with product and partner-facing teams.

Designs, develops, deploys, and sustains Azure infrastructure for AI training and inference workloads. Responsibilities include coding, hardware and software integration, distributed systems, networking, GPU and cluster design, performance optimization, debugging, automation, test-driven engineering, documentation, partner collaboration, and on-call incident response. The role drives scalable, reliable infrastructure and mentors engineers while improving quality, maintainability, and customer outcomes.

Leads software development for healthcare solutions, implementing customer-focused applications and collaborating with R&D teams. Builds enterprise Java/Kotlin applications, full-stack web applications, component libraries, REST API integrations, and cloud-hosted systems. The role requires experience with Spring, PostgreSQL, React or Angular, AWS, healthcare or EMR integration, Agile development, test automation, and unit testing. Occasional travel may be required, including company-paid onboarding travel.

Designs, builds, and scales backend services and integrations for payments, billing, identity, and partner connectivity. Sets technical vision and architecture for distributed systems, leads cross-team delivery, manages production rollouts, builds fault-tolerant services and data pipelines, and mentors engineers. The role partners with product, design, and engineering teams to deliver frequent, reliable improvements for Flex’s rent payment platform.

Design, build, and scale backend services and integrations for payment, billing, identity, and partner systems. Own API scoping, design, implementation, deployment, and production operations with minimal oversight. Build fault-tolerant systems, data pipelines, and scalable architectures while collaborating with product, design, engineering, and external partners. Contribute to reliability monitoring, observability, automation, technical standards, and mentoring in a distributed team.

Design and build backend services and APIs for identity resolution and platform integrations. Optimize event-driven pipelines processing billions of signals, deploy cloud-native services on AWS EKS and Kubernetes, and ensure reliability, observability, and scalability. Collaborate with engineering, product, and data teams to deliver identity solutions while mentoring junior engineers. The role requires expertise in backend or data engineering, distributed systems, streaming technologies, cloud deployment, data modeling, and high-throughput databases.

Own end-to-end full-stack product features using TypeScript, Node.js, React, Python, Kafka, and distributed systems. Design data models, backend services, event pipelines, interfaces, auditability, security controls, and AI agent experiences for a regulated fintech product. Operate production systems, collaborate with AI engineers, and help establish engineering practices on a small remote team.

Design and lead development of high-performance networking infrastructure for large-scale AI training and inference in Azure. Architect low-latency, low-jitter communication frameworks, optimize distributed systems, benchmark scalability, resolve complex networking issues, and improve reliability, observability, and performance. Mentor engineers, create technical designs, manage dependencies, and participate in on-call operations for critical services.

Build and ship AI-powered automation features, third-party integrations, full-stack web applications, and cloud infrastructure. Design background job processing systems, improve reliability and observability, address security risks, contribute product ideas, and mentor junior engineers. The role requires strong TypeScript skills, experience scaling AWS systems with infrastructure as code, and proficiency with React, Node.js, and Postgres.

Lead technical strategy and architecture for a large-scale Content Platform that powers marketing campaigns. Solve ambiguous cross-team problems, design scalable backend and AI-driven systems, mentor senior engineers, and partner with product, design, and marketing to drive execution and engineering standards across the org.

Lead development, testing, and maintenance of scalable accounting integrations using JavaScript, TypeScript, Node.js, and AWS serverless technologies. Design REST APIs, webhooks, OAuth flows, and event-driven systems that synchronize data with external accounting platforms. Diagnose complex issues, improve reliability and performance, document systems, and mentor junior engineers. Use AI-assisted development tools responsibly while managing multiple priorities and supporting high-volume integrations.

Own and improve Attentive's first-party data collection across the JS tag, Cloudflare Workers, and Java backend. Expand edge compute capabilities, build agentic AI systems to detect and fix data-quality issues, harden the event ingestion pipeline for reliability and observability, and lead technical direction on a small autonomous team while mentoring engineers.

Design, develop, and modernize enterprise-scale applications, RESTful APIs, microservices, and distributed systems. Build cloud-neutral solutions across AWS and Azure, support legacy application migrations, participate in architecture and code reviews, troubleshoot production issues, document technical designs, and mentor engineers. The role emphasizes scalable, secure, high-performance backend systems, technical leadership, and engineering best practices.

Build and maintain Safari AI’s cloud infrastructure, including production services, system design, reliability, documentation, and security compliance. The role sets technical direction for the cloud stack, collaborates with engineering and operations teams, improves development processes, and delivers incremental features. Candidates should have 4–6 years of software engineering experience, public cloud expertise, and experience taking complex services from concept through production. Streaming processing and machine learning experience are advantageous.