Top Backend Engineer Jobs in Chicago, IL

Design, build, test, deploy, and support scalable software for Grainger’s customer order platform, including cart, pricing, freight, tax, payment, and invoicing capabilities. Partner with engineers, architects, analysts, stakeholders, and product managers to deliver maintainable solutions. Implement CI/CD and engineering best practices, participate in Agile development, solve complex technical problems, and mentor junior engineers.

Develop and maintain backend software for FreeWheel’s programmatic advertising platform. Responsibilities include designing APIs and applications, writing efficient code, implementing unit and integration tests, documenting development and deployment processes, analyzing integration and architecture needs, collaborating with QA, participating in code reviews, and troubleshooting performance and reliability issues. The role requires onsite work in Chicago two days per week and may involve nights, weekends, and variable schedules.

Build and operate high-throughput backend services for AI agents, calendar, scheduling, integrations, real-time data pipelines, and APIs. Design platform infrastructure, event-driven systems, and client-server protocols using Go, PostgreSQL, Kubernetes, and cloud platforms. Collaborate with AI, product, and frontend teams, improve reliability through testing and infrastructure as code, and mentor junior engineers.

Build and operate GitLab’s Rust-based Knowledge Graph backend supporting SDLC and code indexing, graph queries, MCP endpoints, AI agents, and analytics. Integrate with Rails, ClickHouse, NATS JetStream, and Data Insights systems. Improve reliability, observability, scalability, and operational readiness through testing, metrics, runbooks, alerts, and on-call participation. Collaborate asynchronously across product, data, infrastructure, security, and AI teams while contributing to system design and occasional Ruby or frontend work.

Build and enforce workload safety standards across Affirm’s Amazon EKS fleet. Responsibilities include Kubernetes resource management, workload isolation, disruption handling, cluster capacity analysis, policy automation, production debugging, incident response, fleet-wide rollouts, technical leadership, mentoring, and measuring infrastructure impacts on availability, latency, risk, and cost.

Own and deliver highly available, low-latency backend identity systems supporting consumer onboarding, authentication, and verification. Lead quarterly team goals, guide engineers through ambiguous problems, collaborate with product and design partners, monitor system reliability, improve engineering standards, support on-call operations, and mentor team members. The role requires designing and launching distributed systems at scale using Python or Kotlin, AWS, MySQL, and Kubernetes.

Build and ship backend features end-to-end using Ruby on Rails and SQL. Lead complex technical projects, solve architecture challenges, establish standards, conduct meaningful code reviews, resolve high-risk bugs, document systems, collaborate across engineering teams, and mentor junior engineers.

Leads architecture and hands-on development of scalable backend systems and APIs supporting real-time applications. Owns the engineering lifecycle, writes high-performance code, establishes testing and reliability practices, resolves production issues, guides technical roadmaps, collaborates cross-functionally, and mentors engineers. The role requires expertise in object-oriented backend development, distributed cloud systems, automated testing, system monitoring, and technical leadership.

Lead technical vision and strategy for Affirm’s Cards backend engineering organization. Architect scalable and reliable platforms, guide cross-team initiatives, champion AI adoption and engineering excellence, influence technical roadmaps, and mentor engineers through Staff level. The role requires strong architectural expertise, organizational leadership, project management, communication, and cross-functional collaboration.

Own and deliver backend lakehouse infrastructure goals, lead engineers through complex problems, and build highly available distributed data systems. Collaborate with product, design, analytics, and engineering stakeholders; define scalable technical solutions; improve code quality and engineering standards; monitor operational health; support on-call responsibilities; and mentor team members.

Design and scale foundational APIs and backend services for LogicGate’s multi-tenant GRC platform. Build distributed systems using Java/Kotlin, Spring Boot, AWS, databases, caching, and messaging technologies. Improve reliability, observability, performance, testing, and CI/CD practices. Lead technical design reviews, collaborate cross-functionally, mentor engineers, and use AI coding tools to improve development efficiency.

Own the design, development, deployment, and maintenance of backend services, APIs, databases, integrations, and cloud infrastructure. Build secure REST and GraphQL APIs, optimize relational data systems, modernize service architecture, maintain CI/CD and testing, and implement privacy and security controls. Collaborate with frontend, QA, and product teams, review code, document systems, and mentor developers.

Lead fraud decisioning engineering initiatives by architecting, building, launching, and maintaining complex backend systems. Drive cross-functional projects from definition through monitoring, write high-quality and resilient code, review technical work, mentor engineers, collaborate with Product, ML, Analytics, and Business teams, and contribute to hiring and interview design.

Develop backend tools and systems that improve batch development, testing, workflow efficiency, and reliability. Collaborate with product, infrastructure, design, and analytics teams; break projects into deliverable phases; build scalable, well-tested code; monitor metrics; support system availability and on-call operations; debug code; conduct reviews; and contribute to engineering growth and hiring activities.

Develop and lead cloud-based full-stack and backend systems using microservices, APIs, databases, container orchestration, and public cloud platforms. Provide technical leadership across Agile teams, define service architecture, improve performance and resilience, reduce technical debt, establish engineering standards, mentor developers, and evaluate emerging technologies. The role focuses on foundational cloud infrastructure, observability, connectivity, availability, and operational excellence.

Design, implement, and optimize low-level systems software, networking components, protocols, and performance-critical applications. Develop client-server and socket-based systems using C++ and Python, apply algorithms and memory management techniques, and build comprehensive tests. Debug memory leaks, packet flow, and concurrent execution using GDB and Wireshark. Collaborate with cross-functional teams on modular codebases, technical documentation, code reviews, and release-cycle version control.

Lead architecture, development, and operation of globally scaled payments and billing systems. Own subscription billing, payment providers, invoicing, reconciliation, security, compliance, reliability, and modernization. Use and advance AI-agent workflows for engineering, incident response, testing, and anomaly detection while enforcing strict human review and PCI safeguards. Mentor engineers, guide technical strategy, and collaborate with Product, Finance, Risk, Platform, and Analytics.

Leads modernization of mission-critical database and .NET systems. Responsibilities include refactoring stored procedures, optimizing SQL performance, evolving schemas safely, extracting business logic into maintainable services, and modernizing legacy .NET code. The role establishes testing, dependency injection, observability, deployment-safety, and incident-response practices while collaborating with SRE and DevOps teams. It requires deep SQL Server expertise and experience maintaining production stability during large-scale software modernization.

Design and implement backend APIs, microservices, and checkout platform components for Affirm’s financial products. Own system health, improve performance and reliability, collaborate across engineering teams, and contribute to technical standards, tooling, and processes. The role requires developing, testing, and shipping high-quality software at scale while making customer-centric technical decisions.

Develop and optimize low-level systems software using C++ and Python. Design networking components, socket communications, and protocol resolvers; implement algorithms and performance improvements; create unit, integration, and stress tests; debug memory, networking, and concurrency issues with GDB and Wireshark; and collaborate on modular codebases and release version control.

Build and lead development of high-availability backend services for Affirm’s card loan platform. Design scalable APIs, data models, microservices, and event-driven systems supporting real-time loan attribution, approvals, origination, and refunds. Drive technical strategy, troubleshoot complex performance issues, collaborate with cross-functional teams, and mentor engineers while ensuring long-term system robustness and scalability.

Lead backend engineering strategy for Affirm’s search and recommendation platform. Design and launch highly available distributed systems, guide technical architecture and execution, improve team operations and reliability, establish engineering quality standards, collaborate with product, design, and analytics, and mentor engineers. The role focuses on search, recommendations, consumer shopping experiences, monetization, and scalable platform foundations.

Develop and scale backend streaming and data infrastructure using Kafka, Flink, AWS, Kubernetes, and related technologies. Break down projects, deliver tested software, collaborate with product and engineering teams, monitor system availability, participate in on-call support, debug code, conduct code reviews, and contribute to team development.

Architect, build, and operate large-scale relational and distributed SQL database infrastructure. Responsibilities include database control-plane automation, provisioning, failover, backups, upgrades, zero-downtime migrations, Kubernetes networking, connection proxy optimization, reliability monitoring, capacity planning, and operational support. The role also leads technical delivery, mentors engineers, establishes quality standards, collaborates cross-functionally, and contributes to team roadmap and on-call operations.

Build and operate production-grade Python backend services, APIs, distributed systems, data pipelines, and agentic workflows for an AI observability platform. Own ambiguous projects from prototyping through architecture, testing, deployment, and ongoing operation. Collaborate with product, machine learning, and infrastructure teams, while contributing React front ends when needed. The role requires strong backend depth, distributed-systems expertise, cloud experience, and end-to-end product ownership.