Top Senior Software Engineer Jobs in Milwaukee, WI

Evaluate AI coding agents such as Codex, Claude Code, and Cursor for engineering judgment, response quality, reasoning, explanations, and usefulness. Provide clear written and recorded feedback, distinguish quality levels, and help define standards for excellent AI-assisted development interactions. This contract role requires senior-level software engineering experience, strong Python or TypeScript/JavaScript skills, familiarity with modern AI development workflows, and excellent English communication.

Evaluate AI coding-agent interactions for correctness, usefulness, engineering judgment, explanation quality, and user trust. Provide clear, opinionated written feedback, distinguish response-quality levels, and help define standards for tools such as OpenAI Codex, Claude Code, and Cursor. The role requires senior-level software engineering experience, strong TypeScript/JavaScript or Python skills, hands-on AI-assisted development experience, excellent English communication, and the ability to assess code without executing or reviewing every line.

Build and operate full-stack certificate management, security, monitoring, and vulnerability products. Develop TypeScript APIs and React frontends, design MySQL schemas, manage AWS workers and Kubernetes infrastructure, maintain legacy .NET and Python services, integrate partner APIs, improve CI/CD and observability, participate in on-call support, and develop AI-assisted features. The role includes code reviews, testing, incident resolution, technical documentation, and mentoring engineers.

Design and scale Cohere’s Model Vault backend and inference platform. Lead architecture for authentication, deployments, billing, metering, customer lifecycle, and cloud control-plane services. Build reliable distributed systems with strong guarantees for security, privacy, consistency, isolation, observability, and failure recovery. Drive technically complex initiatives from threat modeling and architecture through implementation, production rollout, operations, and iteration at enterprise scale.

Develop and support software applications, REST and ASP.NET web services, distributed systems, data integrations, and storage solutions. Analyze requirements, optimize performance, resolve application issues, implement security and data protection, and collaborate with product, business, and QA teams. The role includes technical documentation, quality reviews, managing competing priorities, and mentoring less experienced developers.

Build and maintain full-stack software for startup clients, including backend services, frontend experiences, new features, redesigns, bug fixes, and product improvements. Collaborate daily with product managers, designers, and engineers in a distributed, agile environment. Take ownership across the technology stack, write clean maintainable code, contribute to client missions, and support team growth and knowledge sharing.

Design and implement scalable backend services for MoneyGram’s core transaction and API platforms. Responsibilities include architecture, microservices, APIs, event-driven systems, integrations, cloud development, CI/CD automation, testing, deployment, operational excellence, and engineering standards. The role collaborates with product, engineering, and QA teams, mentors junior engineers, leads complex technical solutions, and influences technical direction in an agile environment.

Lead technical direction for Elastic’s billing experience platform. Design and evolve public and internal APIs, build full-stack billing and account-management features, and shape scalable architecture and data models. Improve reliability, observability, deployment, CI/CD, and incident response across cloud services. Mentor engineers, review technical work, influence roadmap priorities, collaborate across Product, Design, SRE, Finance, and Cloud teams, and participate in on-call rotations.

Design and scale ARM64 compute platform infrastructure, hypervisor integrations, instance management, resource orchestration tools, and compute APIs. Develop and maintain low-level services using Python, Go, or compiled systems languages. Collaborate with hardware and global engineering teams, participate in design reviews, debug distributed Linux systems, and mentor junior engineers.

The Senior Software Engineer will enhance the core product by developing features and tools for Chainguard Images, collaborating with teams and ensuring product quality.

Design, implement, and maintain scalable, secure, high-performance backend systems and public-facing APIs. Collaborate with Product and Data Science teams, lead initiatives improving efficiency and system performance, and support customer satisfaction. Work may involve distributed systems, pricing engines, identity management, authentication, authorization, API versioning, deprecation, and rate limiting.

Develop and maintain enterprise full-stack applications using Java Spring Boot, REST APIs, modern front-end frameworks, Oracle Exadata, and OpenShift/Kubernetes. Responsibilities include legacy code analysis, full-lifecycle development and testing, SQL and PL/SQL optimization, microservices deployment, CI/CD, code reviews, architecture discussions, monitoring, and Agile collaboration. The role requires an active transferable IRS MBI moderate-risk public trust investigation, U.S. citizenship, and substantial full-stack and cloud-native development experience.

Build and own Android growth and monetization experiments across subscriptions, pricing, advertising, purchases, and upgrade flows. Partner with product, design, data science, and analytics to instrument experiments, manage staged rollouts, monitor performance, and act on results. Use AI tools throughout development, contribute to Android architecture and engineering practices, participate in on-call support, mentor engineers, and help scale reliable mobile experiences to tens of millions of users.

Design, develop, and maintain scalable billing and invoicing systems using C# and PHP. Lead architecture, code reviews, mentoring, CI/CD improvements, monitoring, database optimization, security, and PCI DSS compliance. Use Claude and Cursor in daily development while validating generated code for correctness, security, performance, and maintainability. Collaborate across Product, Engineering, QA, and support teams to deliver reliable payment-processing services and resolve complex technical issues.

Leads technical direction and cross-team delivery of scalable software capabilities for a digital banking platform. Designs secure APIs, microservices, integrations, data contracts, and reliable full-stack systems. Partners across product, design, security, architecture, data, and engineering; mentors engineers; leads incident response; improves testing, CI/CD, developer tooling, and operational readiness. The role requires hands-on coding, architecture leadership, dependency management, and influence without direct people management.

Designs, develops, configures, and supports Edifecs healthcare EDI solutions and transaction mappings. Works with 837, 834, 835, 820, and 270/271 transactions; troubleshoots transmissions, configures validations, and develops Groovy scripts. Leads Agile and DevOps efforts, mentors engineers, supports QA, and designs scalable AWS applications using containers, microservices, and CI/CD. Provides technical leadership, architecture guidance, performance tuning, and stakeholder consultation.

Leads the architecture, development, testing, deployment, troubleshooting, and sustainment of Appian applications supporting Army systems. Provides technical leadership, code reviews, mentorship, secure coding enforcement, requirements collaboration, Agile participation, integrations, documentation, and compliance with DoD cybersecurity, RMF, STIG, and privileged-access requirements.

Build and improve scalable, accessible Android applications for Wikipedia and Wikimedia users worldwide. Responsibilities include leading technical discovery and system design, implementing Kotlin and Jetpack Compose features, optimizing performance, developing testing and observability practices, managing delivery risks and scope, and collaborating with product, design, analytics, and engineering teams.

Lead software engineering for the Patient Onboarding team, building and improving registration, insurance verification, and care-access workflows. Write full-stack production code, lead complex cross-team initiatives, shape technical direction, improve engineering foundations, and support modern AI-enabled development practices. Collaborate with Product, Design, Analytics, and Engineering to improve patient conversion and system reliability.

Develop and release Esri software for GIS, photogrammetry, remote sensing, defense, and intelligence workflows. Build high-performance image processing capabilities, algorithms, APIs, cloud-friendly desktop and enterprise applications, and support multiple imagery modalities and data formats. Collaborate with developers and product engineers to integrate libraries into ArcGIS, solve complex application-design problems, and mentor junior developers.

Develop and maintain software using C#, .NET, web technologies, SQL Server, and AWS. Participate in the full SDLC and Agile Scrum processes, including design, development, unit testing, defect resolution, backlog refinement, and collaboration with product and QA teams. Build solutions using Microsoft-stack technologies, optimize databases and stored procedures, and support cloud-based application delivery.

Build and scale data pipelines and partner integrations for an end-of-life open-source software dataset. Responsibilities include improving data quality, designing configurable risk-scoring models, integrating Kafka and data lakes, automating package generation and publishing, implementing monitoring and CI/CD, and documenting systems. The role also involves technical design, code reviews, mentoring, and collaboration with product and partner-facing teams.

Leads software development for healthcare solutions, implementing customer-focused applications and collaborating with R&D teams. Builds enterprise Java/Kotlin applications, full-stack web applications, component libraries, REST API integrations, and cloud-hosted systems. The role requires experience with Spring, PostgreSQL, React or Angular, AWS, healthcare or EMR integration, Agile development, test automation, and unit testing. Occasional travel may be required, including company-paid onboarding travel.

Designs, builds, and scales backend services and integrations for payments, billing, identity, and partner connectivity. Sets technical vision and architecture for distributed systems, leads cross-team delivery, manages production rollouts, builds fault-tolerant services and data pipelines, and mentors engineers. The role partners with product, design, and engineering teams to deliver frequent, reliable improvements for Flex’s rent payment platform.

Design, build, and scale backend services and integrations for payment, billing, identity, and partner systems. Own API scoping, design, implementation, deployment, and production operations with minimal oversight. Build fault-tolerant systems, data pipelines, and scalable architectures while collaborating with product, design, engineering, and external partners. Contribute to reliability monitoring, observability, automation, technical standards, and mentoring in a distributed team.