Top Software Engineer Jobs in St. Louis, MO

The role involves leading the design, development, testing, and maintenance of embedded software for real-time systems, while managing projects and mentoring junior engineers.

Support design, development, testing, integration, and maintenance of mission-planning software. Troubleshoot issues, document architectures and requirements, and help improve software processes in an Agile environment.

Develop, validate, and maintain simulation models, visualizations, and frameworks. Integrate simulation software with hardware, collect/process data, execute tests, document results, and modernize legacy simulation systems while collaborating with stakeholders and cross-functional teams using Agile practices.

As a Summer Intern Software Engineer, you'll work on software development projects, apply object-oriented programming, and gain experience with Java and other technologies while participating in professional development and networking activities.

Design, analyze, and quantify data fusion algorithms; author technical documents and algorithm analysis memos; develop prototype algorithms (C++, Python, MATLAB); partner with architects for implementation; collect and analyze sensor data and collaborate with customers on requirements.

Develop innovative software solutions, mentor junior team members, and analyze project requirements in a collaborative environment focused on digital transformation.

The role involves leading software engineering teams, developing large-scale data processing systems, mentoring junior staff, and ensuring project success. You will leverage programming languages and technologies like Java and Python, embracing innovation and technology to enhance delivery.

Lead software efforts in the Battlespace Picture team, ensure requirements adherence, and oversee technical excellence and software integration across missions.

As a Software Engineer, you will build and maintain a native advertising platform, collaborating with teams to enhance user interfaces and improve ad campaign effectiveness.

The Software Engineer - Cloud will design and improve cloud infrastructure and data pipelines, develop AI and tooling solutions to enhance recycling operations using machine learning.

Senior Full-Stack Software Engineer position focusing on building, shipping features, and improving code quality using React, TypeScript, and Ruby on Rails.

As a Software Engineer II in the Credit Decisioning team, you will design and develop backend systems, collaborate with cross-functional teams, and support project delivery and operations.

Design, develop, and maintain AI-powered applications. Collaborate with engineering and product teams to deliver scalable solutions and mentor other engineers. Conduct experiments to guide product decisions.

As a Software Engineer, you'll develop software using Ruby, Javascript, and support AWS infrastructure. Responsibilities include maintaining and building applications, contributing to high-end software releases, and mentoring other engineers.

Build and scale backend services for verification orchestration, decisioning, and fraud detection. Integrate third-party data providers and ML models, develop rule engines, maintain APIs and Kafka events, improve document automation, and enhance observability, compliance, and platform reuse across lending products.

Build and scale full-stack systems and microservices powering engagement features (credit health, financial wellness, gamification). Design event-driven, Kafka-based pipelines, collaborate cross-functionally, support experimentation/A-B testing, ensure regulatory/compliance alignment, and improve reliability and performance of production systems.

Full‑stack engineer building donor and fundraising features using React, TypeScript, REST, and Ruby on Rails. Deliver small-to-medium projects, improve performance and maintainability, participate in code reviews and QA, collaborate with product and design, and contribute to architecture and team mentorship.

The Associate Software Engineer will design, develop, and maintain software for a mission planning system, collaborating with teams and troubleshooting issues.

The Associate Software Engineer will support the design, development, testing, and maintenance of weapon-specific mission planning software for the JMPS, using Agile methodologies with C# and WPF.

Build and scale backend and full-stack systems for enterprise customers: design APIs and platform services, improve observability and reliability, respond to incidents, integrate AI features, and collaborate cross-functionally to deliver high-impact enterprise capabilities.

Design, build, and scale highly performant, highly available backend systems for advanced crypto trading instruments. Architect robust services supporting multiple instrument types, collaborate with product and design, and deliver high-value, observable features for traders worldwide.

As an Infrastructure Software Engineer, you will build and optimize scalable systems for user data management while mentoring peers and collaborating on innovative solutions.

Lead the design and implementation of backend services for data cataloging and ML training systems, focusing on performance and scalability.

Build enterprise-grade authentication, authorization, and identity features across the full stack. Design and implement RBAC, provisioning (SCIM), SSO/OAuth integrations, secure public APIs, and admin workflows for auditing and compliance. Own end-to-end product changes, collaborate on architecture, and mentor engineers to deliver scalable, reliable systems for enterprise customers.

Join the Payments team to design, build, and maintain secure, scalable payment systems. Work across the stack on payment processing, recurring contributions, fraud mitigation, ETL pipelines, testing, monitoring, and operational tooling. Collaborate with product, platform, ops, and security teams to deliver reliable features, debug complex issues, and improve payment workflows while contributing to team documentation and on-call support.