Top Senior Software Engineer Jobs in St. Louis, MO

Leads full-stack software engineering and technical delivery for enterprise applications across the Microsoft .NET and Azure ecosystem. Designs scalable architectures, APIs, integrations, distributed and event-driven systems, and cloud-native solutions. Provides hands-on development, code reviews, troubleshooting, DevOps collaboration, CI/CD, production support, and operational improvement. Mentors engineers, coordinates technical delivery, manages risks and dependencies, and partners with Product, Architecture, Security, QA, and infrastructure teams.

Build and scale a telemedicine platform using React, TypeScript, Python, Flask, and PostgreSQL. Own features through development, deployment, and launch; develop integrations; write tests; conduct design and code reviews; resolve production issues; and collaborate with Product, Design, and Quality teams in a Scrum environment. The role also involves mentoring engineers, improving development processes, and communicating technical decisions to nontechnical stakeholders.

Build and operate reliable, maintainable software for appointment-based businesses. Own product and technical initiatives from design through production, collaborate with Product and Design, contribute to architecture, and develop frontend, backend, or full-stack systems. Ensure quality through testing, code review, observability, and production support while mentoring engineers and improving development practices with AI-assisted tools.

Build and operate high-volume AWS data pipelines and bidirectional CRM integrations for educational fundraising systems. Design idempotent consumers, incremental synchronization, rate limiting, replay, migrations, monitoring, and partner-facing APIs. Collaborate with product, partner, data science, and CRM teams while improving AI-assisted engineering practices. Own major system components or end-to-end architecture, depending on level, and mentor teammates at the higher level.

Build and maintain full-stack donor-facing giving forms, payment flows, recurring giving, memberships, and administrative tools. Own projects from architecture through production support, ensuring reliability, accessibility, performance, and data integrity. Collaborate with product managers, designers, and engineers; mentor junior engineers; contribute to technical standards, security monitoring, hiring, and rotational on-call support. Potentially serve as a Tech Lead for roadmap implementation and technical decision-making.

Build AI platform infrastructure and developer tooling, including API gateways, model routing, integrations, observability, retrieval, caching, and model-serving systems. Develop APIs, microservices, SDKs, and internal tools that connect proprietary real estate data and AI models to production applications. Collaborate with ML engineers, contribute to architecture decisions, and own features through deployment and monitoring.

Lead a portfolio company’s engineering function by writing production code, modernizing the software development lifecycle, coaching engineers, setting the product roadmap, and implementing AI-powered development and product capabilities. The role requires rapidly learning unfamiliar technology stacks, improving legacy codebases without rewrites, operating independently, and partnering closely with general managers, operators, and customers.

Develop and administer STIBO STEP solutions supporting enterprise master data management initiatives. Responsibilities include designing workflows, WebUI interfaces, attributes, validation rules, and integrations; ensuring data quality, governance, and platform performance; troubleshooting complex issues; supporting production operations and SaaS upgrades; and collaborating with Product, stakeholders, and engineering leadership. The role also includes mentoring engineers, estimating work, driving delivery, and implementing product, vendor, and customer data governance frameworks.

Lead development of full-stack, mission-critical products using Angular, React, Node.js, and AWS serverless technologies. Own projects from product definition through deployment, integrate GraphQL APIs and machine learning systems, improve developer experience and CI/CD, collaborate with clinicians and researchers, participate in customer discovery, and mentor engineers while shaping technical architecture and engineering culture.

Lead architecture and hands-on development of Azure Kubernetes Service capabilities for AI workloads. Design secure, reliable, scalable distributed systems; coordinate engineering teams; define testing and deployment strategies; improve observability and operational readiness; investigate production issues; and mentor engineers while advancing engineering practices.

Lead development of scalable Java backend applications and high-availability cloud services. Design architectures, REST APIs, databases, caching systems, and distributed session infrastructure. Mentor engineers, drive technical initiatives, address performance and scalability challenges, and uphold quality and automation practices for endpoint management products.

Design, build, test, deploy, and operate scalable, secure Azure networking software and automation tools. Act as DRI, monitor production, troubleshoot incidents, run root-cause analysis, and drive reliability, performance, and cost improvements. Collaborate with PMs and architects, participate in design/code reviews, mentor engineers, and champion security, privacy, and compliance.

Lead backend engineering strategy for Affirm’s international Identity team. Design and launch highly available distributed systems supporting KYC, user lifecycle management, and identity decisioning. Drive technical planning, cross-functional collaboration, operational excellence, monitoring, testing, and on-call readiness. Establish engineering quality standards, influence architecture, mentor team members, and deliver scalable systems using Python or Kotlin, AWS, MySQL, Spark, and Kubernetes.

Build and scale developer platform capabilities, AI-powered coding and review tools, CI/CD systems, Kubernetes infrastructure, and self-service developer workflows. Improve reliability, security, observability, and delivery speed through automation, reusable templates, guardrails, documentation, and incident-response practices. Collaborate closely with platform teammates, contribute to roadmap decisions, and communicate clearly about progress, blockers, and technical tradeoffs.

Lead performance engineering for massive-scale HPC and AI workloads across InfiniBand-connected GPU clusters. Diagnose communication bottlenecks, analyze fabric behavior, tune RDMA and QoS, develop telemetry tooling, optimize topology-aware communication, benchmark distributed workloads, and collaborate with operations and hardware vendors on next-generation interconnects.

Build and operate Node.js and TypeScript backend services using durable workflows and AI-assisted development. Define service patterns, orchestrate migrations, maintain MCP and AI workflow tooling, and improve observability through metrics, alerts, dashboards, and tracing. Handle production incidents, contribute targeted frontend changes in React and Angular, and collaborate on architecture and code reviews in a fully remote environment.

Design, develop, and maintain provider-facing web portal microservices and highly available business applications. Collaborate with product managers and designers from ideation through deployment and maintenance, make technical decisions, conduct code reviews, mentor engineers, support QA, and contribute to compliance initiatives. The role involves modern and legacy technologies, AWS services, microservice and event-driven architectures, APIs, databases, front-end development, infrastructure as code, and secure handling of PHI.

Design and develop scalable, cloud-native APIs and a greenfield system replacing a legacy platform. Build production software using TypeScript, JavaScript, Node.js, React, GraphQL, REST, SQL, and automated testing. Contribute to architecture, performance tuning, reliability, Azure DevOps pipelines, and agile delivery while applying AI development tools and maintaining strong engineering standards.

Own Telnyx’s global phone-number ordering pipeline, carrier integrations, regulatory automation, AI-powered order review, and Postgres data layer. Build reliable async Python services with retries, rollbacks, queues, SLA monitoring, document verification, auditability, and human escalation. Improve automation across dozens of vendors and 45+ countries while maintaining dashboards, analytics, and operational alerts across a large microservice estate.

Develop and modernize SQL Server-backed data-access systems for medical imaging workflows. Responsibilities include database schema refactoring, query optimization, indexing, migration tooling, secure and reliable data access, CI/CD automation, testing, technical standards, architecture planning, code reviews, and developer mentorship. The role uses Kotlin, jOOQ, SQL Server, Liquibase, Gradle, and containerized testing to improve performance and maintainability without disrupting clinical users.

Owns the design, development, security, performance, and scalability of Cerby’s cross-browser Manifest V3 extension. Builds React and TypeScript experiences across extension surfaces, manages service-worker synchronization and authentication workflows, and ensures secure credential handling. Responsibilities include dependency and supply-chain security, testing, observability, code reviews, mentoring, cross-functional collaboration, and production delivery in an agile remote environment. The role also promotes responsible AI-assisted development practices.

Own the architecture and long-term direction of Alpaca’s Redpanda-based event streaming platform. Lead migration to event-driven systems, design scalable real-time client streaming, establish schema and library standards, shape authentication for streaming, partner on resilience and testing, mentor engineers, influence cross-team technical decisions, and participate in platform on-call. The role primarily uses Go and involves Kubernetes, Helm, PostgreSQL, observability, and distributed systems.

Build and own automated testing frameworks, CI/CD infrastructure, load and stress testing, and chaos engineering practices for a brokerage platform. Write primarily Go, integrate AI and LLM tooling into quality workflows, investigate application and Kubernetes failures, improve developer tooling, and mentor engineers on reliability and test coverage.

Build and architect Alpaca’s algorithmic trading platform, developing high-performance, low-latency brokerage systems. Responsibilities include extensive frontend and backend coding, distributed system design, database and concurrency architecture, high availability, throughput optimization, and object-oriented modeling. The role requires prior experience with trading or exchange systems, including OMS and RMS platforms, and involves making critical technical decisions in a demanding early-stage environment.

Lead design and implementation of Azure full‑stack, scalable skilling platform features. Drive CI/CD, reliability, automation, and AI/LLM-enabled capabilities. Mentor engineers, enforce engineering best practices, coordinate cross-team dependencies, and improve test automation and observability for enterprise-scale services.