Top Principal Software Engineer Jobs in Chicago, IL

Design and develop web applications, mentor teammates, shape architectural decisions, write clean code, conduct testing, and troubleshoot issues.

The Principal Software Engineer will lead the development of Node-based applications, ensuring alignment with business goals and mentoring engineers. Responsibilities include designing scalable systems, managing product requirements, and utilizing AI tools for software development.

Architects and develops secure, high-performance distributed applications, APIs, microservices, and data pipelines on AWS. Leads application architecture, cloud infrastructure, data governance, testing automation, CI/CD, security, performance optimization, and technical modernization. Coordinates complex project lifecycles, manages risks and schedules, advises management, resolves cross-functional technology issues, documents systems, and mentors junior engineers in a financial services environment.

Lead the technical vision and development of Elasticsearch’s core search infrastructure, including indexing, retrieval, query execution, and relevance. Research advances in search systems and algorithms, guide long-term technical roadmaps, collaborate across teams, mentor expert engineers, and contribute hands-on to high-performance distributed software. Serve as a subject-matter authority while driving projects from concept through completion.

Develop and maintain embedded software and firmware for defense systems within the Targeting Business Unit. Responsibilities include requirements analysis, software architecture, coding, testing, debugging, integration, and lifecycle support using C++, Linux or VxWorks, scripting, Agile or Waterfall methods, version control, and planning tools. The role involves collaboration with customers, suppliers, users, and technical teams, with opportunities at Software or Principal level.

Designs, develops, tests, integrates, operates, and maintains embedded software and firmware for defense systems. Responsibilities include software architecture, requirements, coding, debugging, integration on target hardware, and lifecycle support using C++, scripting languages, Linux or VxWorks, Agile or Waterfall methods, version control, and planning tools. The role collaborates with customers, suppliers, users, and technical teams and supports complex systems involving multithreading, distributed processing, multicore, and secure processing.

Build and scale Xbox growth experiences across console, web, and mobile through full-stack engineering and data-driven experimentation. Responsibilities include proposing product hypotheses, designing A/B tests, implementing telemetry and analytics, shipping reliable services and client features, analyzing results, participating in on-call rotation, using AI-enhanced workflows, mentoring engineers, and driving experiments that improve retention and daily active users.

Develops, tests, documents, enhances, and maintains software solutions using established design principles and technical standards. Reviews systems, resolves defects, remediates security vulnerabilities, improves performance, analyzes user stories, and implements business solutions. Participates in software development processes, stays current with technology, mentors engineers, and helps plan and prioritize team development work.

Lead Elasticsearch performance engineering from architecture through production. Develop performance models, optimize distributed systems, profile bottlenecks, build benchmarks, detect regressions, and improve scalability across stateful and serverless architectures. Design AI-assisted optimization and benchmarking tools, collaborate across teams, define performance strategies, and mentor engineers. The role requires deep Java, JVM, concurrency, distributed systems, and search or data-store performance expertise.

Leads the technical strategy, architecture, implementation, and delivery of a scalable ecommerce platform for vehicle discovery, configuration, checkout, payments, order management, fulfillment, and ownership experiences. Builds and tests distributed systems, drives code quality and technical decisions, partners with product and UX teams, simplifies complex problems, and mentors engineers while balancing customer impact, business needs, and long-term technology excellence.

Leads the full lifecycle development of satellite and aerospace software systems, including requirements definition, systems architecture, trade studies, verification, validation, testing, anomaly resolution, integration, deployment, and operations. Supports spacecraft product roadmaps, customization, cost optimization, and heritage-platform reuse. The role also leads multidisciplinary teams and performs specialized systems analyses across safety, reliability, security, certification, and related engineering disciplines.

Lead as a customer‑embedded principal engineer to design, build, and ship production-grade solutions. Translate business needs into technical approaches, influence senior stakeholders, accelerate delivery in ambiguous environments, and transition work to FDE crews while driving long-term account impact.

The Principal Software Engineer will lead the design and build-out of an AI Context Layer, ensuring high-quality data for AI systems, while managing access control and developer interfaces, and leading cross-team projects.

Lead technical design and delivery of cloud-native .NET applications. Architect microservices, event-driven solutions, and APIs; mentor engineers; implement CI/CD, containerization, and DevOps; ensure security and compliance; evaluate emerging technologies and AI-assisted development tools to improve productivity.

Design and implement scalable full-stack solutions for institutional platforms. Lead API and microservices design, cloud (AWS) deployments, CI/CD and DevSecOps, collaborate with product and QA, troubleshoot production, and mentor distributed teams.

Design, architect, and build enterprise Java microservices and APIs; lead technical delivery, mentor engineers, implement cloud-native and CI/CD practices, design database schemas and PL/SQL, and develop blockchain/digital-asset solutions including smart contract work and lifecycle integration in financial services.

Lead technical vision and architecture for Dockers Developer Tools: build a self-service internal platform, CI/CD and build systems, integrate AI/LLM agents, set SDLC tenets, establish standards for observability, security, reliability, and productize internal tooling into customer offerings.

Lead technical direction for a major product domain, reduce architectural debt, mentor engineers, standardize AI-agent workflows, and design scalable backend solutions integrating LLMs and cloud services. Drive cross-team RFCs, cookbook standards, and adopt agentic AI tooling while balancing security, quality, and delivery.

The Principal Software Engineer leads a team to develop full-stack real-time applications, integrates machine learning models, and influences software architecture in cloud environments while supporting healthcare analytics.

Lead end-to-end design, development, and quality of enterprise cloud solutions. Estimate costs, define quality criteria, implement complex systems, manage engineering processes, risks, and dependencies, and mentor teams. Serve as technical lead across large, cross-functional projects to deliver measurable, user-centric healthcare technology solutions.

Drive architecture and technical vision for Elasticsearch core storage and query engine. Lead performance and storage-efficiency improvements, design indexing/serialization/data layouts, mentor engineers, coordinate cross-organizational initiatives, triage community issues, and write idiomatic modern Java for logs and metrics workloads.

Develop, integrate, test, operate, and maintain embedded software, firmware, and computing system components for defense products. Responsibilities include requirements analysis, software architecture, C++ coding, debugging, integration, test automation, and lifecycle process compliance. The role uses virtual platforms, Linux or VxWorks, Agile and DevSecOps practices, and requires collaboration with customers and technical teams. This is a full-time, on-site position in Rolling Meadows, Illinois, requiring U.S. citizenship and a Secret clearance before starting.

Lead technical strategy and architecture across engineering, advise executives, de-risk early-stage ideas, and drive delivery of scalable web and mobile products. Mentor senior engineers, promote cross-team collaboration and AI adoption, partner with product and clinical stakeholders, participate in on-call rotation, and ensure systems meet standards for stability, maintainability, and scalability.

Lead design, development, deployment and support of Salesforce-based applications. Architect scalable solutions, manage releases, mentor and supervise developers, conduct code reviews, provide production support, and participate in full Agile SDLC.

Lead design and implementation of scalable data ingestion, transformation, and search systems for security telemetry. Build and maintain event-streaming pipelines, integrate third-party data sources, partner with product stakeholders, apply AI agents for data mapping and correlation, set engineering standards, improve observability and testing, and mentor junior engineers.