Top Principal Software Engineer Jobs in Chicago, IL

Lead reliability, performance, and operational excellence for large-scale ad-tech distributed systems. Design and operate monitoring, incident response, capacity planning, automation, and secure production infrastructure. Mentor engineers, influence architecture for production readiness, run on-call rotations, and drive continuous improvement of engineering operations and observability.

The Principal Software Engineer will lead platform initiatives, promote AI usage, ensure architecture stability, mentor engineers, and influence technical strategy across teams.

Design, evolve, and optimize Scala-based, low-latency trading services. Lead architecture for scalability and performance, tune JVM/Akka systems, enhance observability, ensure security and regulatory compliance, and mentor junior engineers while collaborating cross-functionally to support 24x7 high-volume trading.

Lead architecture, design, and delivery of PET product features; write production full‑stack code; champion testing, observability, CI/CD and operational readiness; mentor engineers and collaborate with product to shape technical roadmap.

Lead development of core client systems and engine-level infrastructure in Unity/C#. Diagnose and fix cross-cutting performance issues, upgrade third-party SDKs, evolve build tooling, produce design docs, scope multi-week infrastructure initiatives, mentor engineers, and drive profiling, optimization, and architecture changes to enable future features.

As a Senior Principal Engineer, you'll define and drive the technical strategy for customer experience platforms, lead architectural decisions, and mentor engineering teams to enhance customer and agent experiences.

Lead long-term technical strategy and execution across multiple teams, architecting and evolving foundational frontend/backend systems and platforms at massive scale. Drive AI/ML adoption, solve ambiguous, high-impact problems, remain hands-on in critical system design and implementation, and align senior leaders on roadmaps and engineering standards.

Lead architecture and technical execution of scalable, highly available consumer-facing applications across digital channels. Collaborate with stakeholders from ideation through deployment, resolve technical and business problems, evaluate new technologies, provide estimations, mentor engineers, and ensure performance, security, maintainability, and robustness of solutions.

Lead design and build of scalable backend systems and data platforms; own architecture and production deployments; improve reliability, performance, and observability; mentor engineers and collaborate with Product, Data Science, SRE, and Security.

The Principal Software Engineer leads technical vision and strategy for the division, mentors staff, and drives architectural standards across multiple business units.

Lead design and prototyping of generative AI experiences for autonomy development; drive UX for Hivemind products; perform user research, collaborate with CTO and product leads, and deliver reference implementations and integrations across full-stack web and edge systems.

Lead architecture for high-volume, data-intensive distributed systems using Domain Driven Design. Provide project-embedded consultation, prioritize platform capabilities, automate architecture documentation, champion reliability, scalability, security, CI/CD, and cloud-native best practices while communicating complex technical decisions to stakeholders.

Design and develop software to onboard hardware accelerators and optimize storage datapaths for Azure Storage. Drive design, debugging, performance tuning, operations, and cross-team collaboration across research, compute, and storage to improve throughput, scale, reliability, and observability.

Lead architecture, design, and implementation of cloud-native TFDM applications. Drive DevOps/GitOps CI/CD pipelines, containerization (OpenShift/Kubernetes), infrastructure-as-code, AI-assisted development, system modernization, troubleshooting, mentoring, and executive briefings to support deployment, automation, reliability, and security.

Lead architecture and implementation of large-scale, elastic Pub/Sub and messaging services. Define scalable, reliable designs, mentor engineers, drive CI/CD and testing strategies, manage incidents, partner with PMs/EMs, and advance AI tooling across the SDLC to enable real-time analytics and integrations.

Design, develop, test, and integrate embedded software and firmware (Linux/VxWorks) across the full SDLC using OOP C++, scripting, version control, and agile/DevSecOps practices to support complex defense systems and customer integration.

Develop and maintain embedded software and firmware for defense systems using C++ on Linux or VxWorks. Participate in full SDLC: requirements, design, coding, testing, integration. Work with model-based engineering, DevSecOps, version control, and Agile practices; interface with customers, suppliers, and engineering teams. Position may be filled at Software or Principal level and requires US citizenship and government clearance.

Design, develop, test, and integrate embedded software and firmware for defense systems. Apply object-oriented C++ development, scripting, and version-control practices across the full software lifecycle. Work in Agile/DevSecOps and model-based engineering environments, interface with stakeholders, and support on-target hardware integration and debugging.

Drive architecture, design, and implementation of large-scale software systems. Lead technical strategy, mentor engineers, collaborate cross-functionally, ensure code quality and operational reliability, and guide delivery of complex features and platform improvements.

Lead design and implementation of full-stack, large-scale cloud platform capabilities for Microsoft Fabric. Shape architecture, build GraphQL APIs, developer tools, AI-driven experiences, participate in livesite operations, mentor engineers, and drive cross-team initiatives to deliver scalable, reliable developer-facing services.

Senior technical leader owning end-to-end platform strategy, architecture, and delivery for Digital Enablement. Hands-on coding, driving modernization to cloud-native, API/microservices/event-driven designs, embedding AI-first practices, ensuring reliability, observability, and engineering excellence while mentoring teams and influencing cross-functional stakeholders.

As Principal Software Engineer, you'll define and drive Airbnb's performance strategy, lead performance profiling development, mentor engineers, and connect performance outcomes to business objectives.

Lead the architecture of backend services and distributed systems for OpenAI's B2B engineering team, ensuring scalable, reliable, and secure products.

The role involves building robust software solutions, mentoring engineers, analyzing business problems, and contributing to technical strategy in a collaborative environment.

Lead design and reliability of a financial data extraction platform, minimizing human validation through AI, and enhance system correctness for scale.