Top Senior Software Engineer Jobs in St. Louis, MO

As a Software Engineer, you will design, develop, and integrate capabilities in a complex system while collaborating with team members to deliver impactful solutions.

Lead and deliver moderately complex software initiatives across the Investment Solutions team. Design, code, test, debug, and document solutions; review technical challenges; resolve issues; mentor junior staff; collaborate with product owners, architects, QA, and business stakeholders; support deployments and platform improvements while leveraging AI-assisted development tools.

Lead Site Reliability Engineer responsible for driving stability, resiliency, performance, and security of enterprise platforms. Define SLIs/SLOs, implement observability and automation, lead incident management and toil reduction, advise leadership, enforce reliability standards, and collaborate across development, product, and operations to ensure high availability and continuous improvement.

Lead architectural modernization of enterprise .NET applications into cloud-native microservices. Define technical strategy, cloud architecture (AWS/GCP), DevSecOps/CI-CD, mentor engineers, drive API-first and front-end modernization, and align technology with business goals.

Lead architecture, provisioning, and optimization of on-premises and cloud lab/test environments. Drive CI/CD and deployment pipelines, integration testing workflows, observability, security/compliance (CIS, NIST, SOC 2, FedRAMP), and mentor engineers. Act as technical liaison across programs and external partners to ensure scalable, secure, repeatable lab operations and data-driven insights.

Lead and manage a team of software verification engineers to design, develop, and execute requirements-based test plans and automated test frameworks. Perform functional, performance, and safety verification, report defects, and support formal qualification testing. Coordinate with program management, systems engineers, and developers in an Agile, CI/CD-driven environment for defense flight systems.

Design, develop, test, and maintain web-based geospatial intelligence applications using Java and/or Python. Integrate relational and non-relational data stores, apply secure coding practices, participate in Agile sprints, conduct code reviews and testing, support performance tuning, and mentor junior developers while maintaining required security clearance.

As a Founding Software Engineer, you'll design, develop, and maintain robust backend systems, create user-facing AI features, and collaborate with teams to enhance healthcare tools.

Design, build, and maintain high-throughput data ingestion and processing pipelines; integrate AI-powered infrastructure; implement and support complex computing algorithms and distributed services; own systems end-to-end including architecture, observability, reliability, and operational support; lead architectural initiatives and reduce system complexity while maintaining performance on large-scale real-time data.

Lead technical strategy and delivery for backend marketplace/search systems. Collaborate with PM, design, and analytics; own operational reliability, monitoring, on-call, testing, and runbooks; set code/design standards; drive major feature delivery and deprecations; mentor and develop engineering talent.

Develop, integrate, debug, and test software for geospatial intelligence systems. Write validation and unit tests, program in Python/Java and other frameworks, use CI/CD, containerization, databases, and cloud technologies, and collaborate using Agile and team tools.

Lead design, development, testing, debugging, and maintenance of embedded software for vehicle health management on air vehicle/avionics systems. Translate customer requirements into software designs, integrate software with specialized hardware, improve system efficiency and stability, guide testing and adoption of emerging tools, and oversee supplier and internal team performance and embedded software project management.

Develop, integrate, test, debug, and maintain embedded C/C++/C# software for NDI and ATE systems (robotics, LIDAR, ultrasound, RF, electrical test equipment). Update UIs, build unit/functional tests, maintain GitLab CI/CD pipelines and Windows runners, and collaborate with cross-functional teams to ensure safety, compliance, and integration with hardware.

Lead complex software projects, mentor engineers, and set technical direction at Vanta while contributing to security and compliance solutions.

Design, implement, and optimize high-performance backend systems in Rust for an xOT security platform. Participate across the development lifecycle—debugging, testing, and performance tuning—while integrating relational and NoSQL data stores, microservices, third-party devices, and AI tools. Provide technical leadership, code review feedback, and promote secure, reliable, observable distributed systems.

Design and develop backend services and APIs for identity resolution, optimize event-driven systems, and enhance system reliability. Mentor engineers and influence architectural decisions.

As a Lead Software Engineer, you'll design and develop GenAI platforms, integrate LLMs, mentor engineers, and solve technical challenges for scalable solutions.

Serve as the technical IC leader for the Provider organization: set technical roadmap and engineering standards, design and review architectures, drive cross-team initiatives, mentor engineers, and deliver high-throughput, low-latency, cloud-based microservice systems for provider-focused products.

Own end-to-end frontend development for core crypto payment flows across web and mobile. Improve latency, availability, and SLOs; build user-facing features (contacts, real-time transaction status); identify and fix performance bottlenecks; partner with product/design/backend; mentor junior engineers to reduce customer friction at scale.

Lead design and implementation of the PSA Liquidity Platform connecting buyers and sellers. Build buyer tooling, matching/ranking engines, and seller experiences. Architect and operate microservices and Kafka-driven systems on Kubernetes/AWS, instrument observability, apply AI tooling across the SDLC, and drive cross-functional delivery from 0-to-1 while owning end-to-end outcomes.

Lead backend and full-stack work on the Payments team, building multi-gateway integrations (Stripe, PayPal), payment APIs, and customer payment UIs. Ensure secure, compliant (PCI-DSS) payment flows, reliability, observability, and scalability across AWS/Kubernetes microservices. Partner cross-functionally to design architecture, implement settlement/reconciliation, and maintain high availability.

Build and scale full-stack systems to improve provider onboarding and supply; design distributed, maintainable services; lead high-priority projects; mentor engineers; integrate AI-assisted and LLM-based features; drive provider-facing product quality and reliability.

Design, build, and own backend services for prediction markets across market lifecycle: creation, trading, oracle resolution, settlement, and payouts. Build low-latency, high-throughput microservices and event-driven systems, drive reliability via SLOs and observability, lead incident response, set technical standards, and mentor engineers while partnering cross-functionally to deliver product and compliance-aligned roadmaps.

Lead design and delivery of complex web and mobile product areas, build and maintain React/React Native applications, architect scalable systems and APIs, optimize databases and performance, drive engineering standards and test coverage, mentor engineers, and collaborate with leadership and stakeholders in a fully remote environment.

Design, develop, validate, and integrate simulation models, visualizations, virtual environments, and frameworks for flight trainers. Collaborate with stakeholders and cross-functional teams, maintain technical documentation, execute verification/validation and testing, support project management and proposals, mentor junior engineers, and implement emerging tools and process improvements. Deliver software across the full lifecycle in an agile environment.