Top Software Engineer Jobs in St. Louis, MO

Implement EVM-compatible features, optimize gas usage, develop and test smart contracts, collaborate on Ethereum infrastructure, troubleshoot Ethereum issues, and stay current with Ethereum advancements.

Develop and maintain high-security mobile applications using React Native, Swift, or Kotlin. Implement biometric authentication and secure key storage, collaborate with cross-functional teams to deliver features, troubleshoot and optimize app performance, and propose enhancements based on emerging technologies.

Build and maintain end-to-end web applications powering sales and operations. Design tools for quoting, scheduling, and fulfillment, integrate AI into products, collaborate on UX, ship high-impact features, and contribute to architecture, deployment, and engineering culture.

Build and maintain full-stack web systems (Node.js/TypeScript backend, Postgres, React) and AI-enabled features. Design end-to-end features, collaborate with educators and TAs, iterate in a small team, and deliver production-quality user-facing functionality.

As a Full Stack Software Engineer at Goodbill, you'll develop data systems and user experiences, work with diverse data sources, and integrate AI features, ensuring high-quality consumer-facing applications.

Lead product and technical discovery for a new initiative, build prototypes and end-to-end MVPs, define metrics and decision processes, rightsize architecture for iteration and integrations, and engage customers for feedback while coordinating external PM/design/business stakeholders.

Design, build, and maintain data platform tools, ensuring data quality and integrity. Collaborate with data science teams and enforce best software practices.

Mudflap seeks software engineers to build and scale their payments platform using Ruby on Rails, collaborating cross-functionally and owning features end-to-end.

The Senior iOS Engineer will drive key engineering decisions, enhance the iOS app, and engage in product strategy discussions. Responsibilities include shipping production code and maintaining app architecture.

The Software Engineer will build features across the stack, design AI/LLM-driven workflows, translate requirements, and collaborate closely with the founding team and customers.

Full-stack feature-team engineer working across UI, JavaScript, and backend to build scalable investment portfolio management web applications. Gather requirements with product and users, design solutions, implement and deploy code, and operate in Linux environments. Emphasis on strong computing fundamentals, Ruby on Rails proficiency, user workflow understanding, and clear communication.

The Senior Full-Stack Software Engineer will design, build, and scale backend services and APIs for financial transactions while collaborating with frontend engineers and contributing to technical design.

As a Software Engineer at Espresso, you will design and implement core blockchain infrastructure in Rust, focusing on transaction processing and consensus.

The role involves leading frontend development, maintaining UI components, overseeing CI/CD pipelines, mentoring engineers, and enhancing application performance in collaboration with cross-functional teams.

Design and develop real-time embedded software for safety-critical avionics and space systems. Implement software (Ada or C++) meeting DAL A / LOR Level 1 standards. Work on features like synthetic vision, flight management, guidance/navigation, and datalink. On-site in St. Louis; U.S. Person required.

Design and implement complex low latency, high throughput software for financial data distribution, conduct testing, and improve software reliability.

Lead end-to-end design, development, and delivery of full‑stack features; drive architecture and code reviews; coordinate engineering work, write design docs and tests, and participate in Agile ceremonies. Must have blockchain/crypto experience.

Design and implement PostgreSQL internals and indexing/query features for large-scale document workloads, extend query engine with BSON-aware operators and custom scan nodes, tune index pruning and storage, profile distributed systems for performance, collaborate with open-source DocumentDB/PostgreSQL communities, and participate in design/code reviews.

Design, implement, and operate highly scalable Azure cloud services and full‑stack features for Compute Manager. Own design, coding, debugging, reliability, and on‑call operations as a DRI. Collaborate across teams to improve availability, performance, observability, and run distributed systems at hyperscale.

Design and deliver large-scale, resilient AI and Kubernetes infrastructure for hybrid environments. Implement, optimize, and maintain cloud-native, container orchestration solutions; integrate AI capabilities; participate in on-call rotations; mentor engineers and drive reliability, observability, and performance at scale.

Design and implement scalable first-mile networking solutions for Microsoft 365 Substrate and COSMIC. Drive design, dependency identification, coding, optimization, debugging, and on-call monitoring. Analyze production telemetry to improve reliability, performance, and observability. Act as a DRI, lead design and release plans, and collaborate with stakeholders to meet product requirements at global scale.

Leads the design, implementation, optimization, and support of highly scalable Azure Storage services. Responsibilities include end-to-end performance testing, benchmarking, automation, profiling, bottleneck and root-cause analysis across compute, storage, and networking layers, KPI definition, scaling recommendations, and operational incident response. The role collaborates across teams, drives project and release plans, supports reliable and secure services, and mentors engineers while participating in on-call responsibilities.

Lead design and delivery of enhancements to a next-generation AI agent platform. Own large features and infrastructure, mentor engineers, set technical standards, drive cross-team initiatives, improve reliability and SLOs, and influence product and process decisions to scale systems supporting millions of interactions.

The Principal Software Engineer will provide architectural guidance, mentor developers, manage risks, and ensure high-quality software production across various teams and product areas.

As a Senior Software Engineer, you will build and operate Upbound Spaces, resolve issues in SaaS environments, develop features, support project lifecycles, manage Kubernetes services, and enhance operational tools.