Top Software Engineer Jobs in St. Louis, MO

Build and launch backend identity decisioning systems that validate consumer identity and satisfy KYC regulations. Collaborate with Product, Compliance, Auth, Fraud, Analytics, and engineering teams; decompose projects, write tested and extensible code, monitor system metrics, support availability and on-call operations, debug code, participate in reviews, and contribute to technical decisions and team development.

Leads performance engineering across the organization by designing load-testing and data-generation frameworks, defining benchmarks and standards, analyzing application, database, and system behavior, and guiding teams in performance optimization. Builds reusable tooling and best practices using k6, JavaScript, Grafana, and InfluxDB while addressing scalability, latency, throughput, and reliability challenges in distributed cloud-native systems.

Build and deploy full-stack healthcare financial products used by millions of patients. Develop AI- and ML-powered features, integrate LLMs, enhance an AI billing assistant, and create patient payment solutions. Collaborate with product, design, and partner engineering teams to deliver production-ready software. Contribute to technical planning, coordinate complex development efforts, mentor peers, and maintain high standards for testing, code quality, efficiency, and technical debt management.

Develop, test, and maintain mission-planning weapon software within a SAFe Agile scrum team. Translate requirements into designs, implement and integrate microservices (C#/C++ back end, JavaScript/TypeScript/React front end), debug issues, write documentation, and perform unit/integration/system-level testing and validation.

Leads architecture, development, integration, testing, validation, and modernization of simulation frameworks, models, tools, and embedded real-time software. Serves as a technical expert for Boeing’s Test Development Kit, advises stakeholders on simulation requirements, integrates software with hardware, analyzes system performance, and oversees simulation software project activities. Requires extensive object-oriented development, modeling and simulation, Linux systems, and hardware-software integration experience.

Design, modernize, and maintain full-stack applications and microservices using React, Node.js, .NET, and Azure. Lead legacy-to-cloud migrations, data integration workflows, backend data architectures, AI-powered automation, and frontend modernization. Collaborate across scrum teams while ensuring security, disaster recovery, regulatory compliance, and platform stability.

Designs, develops, tests, integrates, and maintains non-embedded software for the Navy Tomahawk missile program. Responsibilities include MBSE, requirements management and verification, system architecture, software development, testing, interface coordination, debugging, documentation, and software process improvement. The role collaborates across disciplines, supports systems integration, ensures compliance with customer and government standards, and provides technical guidance to less experienced engineers.

Develop and deploy customer-focused web, mobile, and backend applications across the full software stack. Design major features, contribute to architecture decisions, conduct code reviews, and ensure secure, high-quality implementations. Collaborate with stakeholders and cross-functional teams using Agile and SDLC practices. Manage version control, CI/CD, environments, and releases; maintain automated test coverage and perform root-cause analysis. Build and optimize relational data solutions using SQL Server, including complex queries, stored procedures, and performance tuning.

Develops scalable software applications across digital channels using modern programming languages and technologies. Responsibilities include software design, coding, code reviews, technical solution development, agile and Scrum participation, story and task creation, sprint execution, production monitoring, and issue escalation. The role requires collaboration throughout the software development lifecycle, attention to scalability and performance, and adherence to engineering best practices.

Design, build, and operate high-throughput backend platforms and shared services, including request routing, traffic management, caching, asynchronous jobs, and durable event processing. The role requires distributed systems expertise, hands-on backend development, cross-team technical leadership, stakeholder management, mentoring, and ownership of multi-quarter platform initiatives. Preferred experience includes Kubernetes platforms, open-source infrastructure, service meshes, workflow orchestration, backward-compatible APIs, and technical community contributions.

Develop and maintain cloud-native, non-embedded software and microservices for aircraft and vehicle health management platforms. Responsibilities include software architecture, design, coding, testing, integration, debugging, root-cause analysis, customer support, technology evaluation, process improvement, and participation across the Agile software development lifecycle within a CI/CD environment.

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 full-stack development for Huntress’s SOC platform, building analyst-facing investigation, triage, remediation, queueing, and customer reporting experiences. Shape architecture, data models, interfaces, security practices, reliability, observability, and testing while mentoring engineers and partnering with Product, UX, and SOC stakeholders. The role emphasizes Ruby on Rails, modern frontend development, cloud infrastructure, relational databases, and technical leadership across complex cybersecurity software products.

Paid, full-time software engineering internship supporting the SOC Operational Intelligence team. Responsibilities include developing Python data pipelines and packages, contributing to internal web applications, supporting AI agents and bots, writing automated tests, and improving developer tooling. The intern will work on production software, ETL pipelines, operational automation, and integrations with systems such as Jira, Ivanti, and Datadog while participating in mentorship, networking, professional development, and team projects.

Paid, full-time software engineering internship supporting workforce management, technician scheduling, and dispatch tools. Interns will build features across web applications, APIs, databases, and cloud services; use AI-assisted development and pattern analysis; and participate in the full software development lifecycle. The program also includes mentorship, professional development, networking, community service, and final presentations.

Paid, full-time software engineering internship supporting Salesforce and CSML development, system integrations, testing, troubleshooting, automation, configuration, technical documentation, and product workflow changes. The intern will contribute to backlog refinement and sprint deliverables under supervision while participating in professional development, mentorship, networking, and cohort activities.

Paid, full-time software engineering internship supporting Netcracker CPQ configuration and development. Responsibilities include analyzing Salesforce and downstream integrations, testing and troubleshooting changes, documenting product configurations and workflows, and assisting with sprint deliverables under supervision. The intern will gain experience with CPQ engineering, pricing logic, order management, and telecommunications systems while participating in mentorship, professional development, and networking activities.

Paid, full-time software engineering internship supporting a payments engineering team. The intern will learn payment processing, participate in the software development lifecycle, practice AI-assisted development, explore monitoring tools, shadow production operations, and join stand-ups and code reviews. The program also includes mentorship, networking, professional development, and cross-functional activities.

Lead the design and delivery of complex distributed systems and high-impact product initiatives for Toast’s Catering & Events platform. Own critical architecture, drive technical strategy, improve scalability and reliability, mentor engineers, establish engineering best practices, and collaborate with Product and Design. The role also involves applying AI tools to improve developer productivity and enable new capabilities.

Design and deliver scalable, secure software systems for Bankrate’s digital products. Responsibilities include shaping architecture, developing APIs and cloud services, optimizing CI/CD pipelines, partnering with product and design, delivering large initiatives independently, resolving cross-team technical issues, mentoring engineers, improving engineering standards, and evaluating tools that enhance reliability, performance, and team productivity.

Lead the design, development, and delivery of scalable payroll onboarding software. Drive technically complex initiatives, influence architecture and roadmaps, collaborate across product, design, and engineering, improve reliability, promote coding best practices, mentor engineers, and use AI tools to enhance development productivity.

Leads technical initiatives for Toast’s restaurant scheduling product, designing and delivering scalable full-stack software. Responsibilities include architecture, API and system design, roadmap influence, cross-functional collaboration, engineering quality, performance, and technical leadership. The role also promotes AI-assisted development and improved employee and customer experiences.

Designs, develops, tests, operates, and maintains mainframe software using COBOL, DB2, JCL, and VSAM. Owns production-ready code, participates in code reviews, analyzes failures, and applies scalable, reliable architectural practices. Collaborates with engineering teams, product owners, scrum masters, vendors, and customers within an Agile and DevOps environment. Ensures compliance, security, software reliability, and continuous improvement while delivering incremental features.

Build and maintain backend services and metadata pipelines supporting data discovery, governance, and AI/ML workflows. Responsibilities include integrating relational databases, developing Java, Node.js, and Python services, optimizing distributed pipelines, implementing Terraform infrastructure, supporting GitLab CI/CD, and writing comprehensive tests. The role also involves troubleshooting scalability and reliability issues, designing asynchronous workflows, and collaborating on modern data lake, search, metadata, and LLM-enabled technologies.

Lead the architecture and technical direction of Forward Financing’s core fintech platform. Design scalable distributed backend systems, guide cross-team initiatives, establish engineering best practices, resolve incidents, and mentor engineers. The role owns the technical roadmap and architectural vision while partnering across teams to improve reliability, observability, code quality, and delivery. Ruby on Rails expertise is required, along with strong communication, influence, agile development experience, and a broad backend or full-stack perspective.