Top Software Engineer Jobs in St. Louis, MO

Provide hands-on technical leadership for Keeper’s cross-platform browser extension architecture. Design secure, scalable solutions using JavaScript and TypeScript; guide extension components, messaging, storage, APIs, native integrations, performance, and reliability. Lead architecture and design reviews, security collaboration, modernization efforts, and cross-functional technical decisions while mentoring senior engineers. The role requires broad full-stack expertise across cloud infrastructure, distributed systems, databases, application security, CI/CD, and modern web technologies.

Reviews and evaluates engineering, infrastructure, and platform documents and work products for technical accuracy, completeness, clarity, consistency, and relevance. Provides structured feedback, identifies errors and gaps, compares technical approaches, and follows defined evaluation frameworks. Requires independent work, strong communication, analytical ability, and professional engineering judgment. The role is fully remote and supports varied technical evaluation projects as an independent contractor.

Design, develop, deploy, and maintain end-to-end cloud-hosted and cloud-native applications for federal clients. Collaborate with technical and business leads to translate requirements into solutions, manage software development lifecycle activities, follow coding and architecture standards, and deliver tested artifacts. The role includes API and cloud architecture, infrastructure-as-code, Agile development, application security, and responsible use of AI tools to accelerate testing.

Co-found and lead the technical direction of a new B2B AI venture. Own problem framing, architecture, system design, product judgment, AI product development, customer discovery, verification, fundraising support, and eventual technical team building. Build maintainable AI and agentic systems that solve real customer workflows, prioritizing traction before scale. The role requires a full-time, exclusive founder commitment with meaningful equity and authority.

Develop client-side features for a complex live multiplayer mobile game using Unity3D. Responsibilities include implementing LiveOps content, writing production-ready code, designing feature architecture, optimizing mobile performance, integrating assets, improving asset workflows, and collaborating with international interdisciplinary teams across shared game systems.

Lead architecture and hands-on development for risk, fraud, scam prevention, money operations, reconciliations, and chargebacks. Build resilient, low-latency, event-driven financial systems with auditable ledgers, strong correctness, and high availability. Mentor engineers, establish technical direction, support production ownership, and collaborate with Product, Data/ML, Compliance, and engineering leaders. Apply AI-assisted tooling and deliver scalable, compliant services across global payment infrastructure.

Develop and maintain scalable, low-maintenance software with a small team. Advise client teams on modern software development practices, apply test-driven development, and continue building technical skills through ongoing training and personal development.

Lead the 0-to-1 architecture, development, testing, and launch of Riverside Insights’ Reach platform and next-generation CogAT assessment. Build and manage a 6–10 engineer team, make build-versus-buy decisions, oversee AWS infrastructure and regulated-data compliance, lead customer migration, and translate product roadmaps into technical execution. The role is hands-on, requiring active coding, full-stack fluency, AI-native development, cross-functional partnership, and senior leadership communication.

As a Software Engineer - Backend, you will develop products and manage engineering infrastructure, focusing on system design, security, and code quality.

Develop and maintain Python backend services, primarily with Flask, while designing scalable architecture and integrating legacy systems. Build AWS solutions using Lambda, Cognito, SNS, SQS, and DynamoDB; maintain CI/CD pipelines and infrastructure as code with OpenTofu and Terraform. Collaborate in an Agile/Scrum environment, contribute to technical decisions and engineering standards, review code, and mentor junior developers.