Top Software Engineer Jobs in St. Louis, MO

This role involves developing the Charles River system during implementation, requiring expertise in Charles River API and trading systems development.

Design and implement an LLVM-based JIT backend for NVIDIA GPUs, develop compiler passes and optimizations to meet performance and compile-time targets, collaborate with hardware and application teams to resolve issues, apply modern compiler technologies, and influence future GPU architectures.

This role involves installing and configuring JBOSS-BRMS, developing and deploying complex rules in DROOLS, and designing RESTful web services. Responsibilities also include performance tuning and creating test data for JBOSS-BRMS solutions.

Design and drive systems architecture, standards, and design patterns. Collaborate with stakeholders to gather requirements, produce cost/benefit and ROI analyses, implement API/microservices solutions, and train and mentor the IT team. Apply development language expertise with some Pega knowledge.

Develop and maintain Java-based applications using REST/SOAP services, Hibernate/JPA, and Spring. Implement CI pipelines, unit/integration tests, manage source control and app servers, design/optimize databases, document technical solutions, and liaise with clients and development teams.

Lead design and implementation of iOS and Android applications, including offline data storage and API integrations (e.g., Salesforce). Oversee configuration, testing, data conversion, and system interface definition. Analyze specifications, recommend configuration changes, and work directly with client implementation teams to deliver large-scale business application solutions.

The C# Developer will enhance and develop applications across various tiers, requiring strong analysis, design skills and proficiency in C# and .NET environments.

The Big Data Architect will design and implement solutions using IBM Big Insights and troubleshoot related technologies while coordinating travel to Toronto monthly.

Volunteer Principal Front End Developer to build React/React Native web and mobile features, mentor engineers, implement scalable full‑stack solutions, ensure cross‑browser compatibility and testing, work with Node/MongoDB/AWS, attend weekly standups, and support a fundraising launch. Minimum 4 hours/week commitment.

Volunteer Principal Full Stack Engineer to lead and contribute across frontend and backend (React/React Native, Node.js, MongoDB). Own feature development, mentor engineers, collaborate with product/design, ship scalable code, and support CI processes. Must commit 4+ hours weekly and attend a weekly standup; first task includes launching a fundraising campaign.

Build and scale Flywheel’s AI-native content platform as its first technical hire. Responsibilities include backend systems, data pipelines, content-generation workflows, web scrapers, integrations, AI product experiences, and customer-facing interfaces. The role requires end-to-end ownership, production LLM experience or rapid learning ability, strong product judgment, and comfort working directly with founders and users in an in-person London environment.