Top Backend Engineer Jobs in Chicago, IL

Develop and maintain Ruby on Rails backend systems supporting solar development, value evaluation, and loan servicing. Responsibilities include writing and reviewing code, maintaining CI/CD pipelines, solving complex domain problems, collaborating with Product and company experts, shaping architecture and technical direction, and improving engineering processes as the company scales.

Design and maintain scalable backend systems in a distributed microservices architecture. Build RESTful APIs, integrate third-party vendors, optimize SQL and NoSQL databases, and implement messaging, observability, CI/CD, and cloud infrastructure practices. Lead engineering initiatives from requirements through delivery, contribute to technical strategy, document systems, and improve reliability, performance, and scalability across user-facing applications.

Build and ship healthcare software across the frontend, APIs, and databases. Own features end to end, write tested and maintainable code, prototype with patients and care teams, and use AI tools such as Cursor and Claude Code in daily development. Design scalable systems, improve performance, accessibility, and reliability, and contribute to trustworthy automation in a fast-paced startup environment.

Build, architect, and own moderate-to-complex backend components; lead small teams or projects; provide technical guidance and code reviews; deliver end-to-end backend services focused on AI-enabled customer data insights, onboarding, messaging/calling features, and scalable data management for a growing user base.

Lead backend engineering strategy for Affirm’s international Identity team. Design and launch highly available distributed systems supporting KYC, user lifecycle management, and identity decisioning. Drive technical planning, cross-functional collaboration, operational excellence, monitoring, testing, and on-call readiness. Establish engineering quality standards, influence architecture, mentor team members, and deliver scalable systems using Python or Kotlin, AWS, MySQL, Spark, and Kubernetes.

Design and scale production-grade asynchronous backend systems in Python, including REST/WebSocket APIs, multi-agent LLM workflows, provider-agnostic integrations, and RAG pipelines. Build schemas and migrations, optimize relational databases, instrument services, and own CI/CD from testing through deployment. Establish AI governance around code review, provenance, licensing, security, compliance, and customer data. Drive architecture and product ideas from conception through production.

Build and operate the backend platform for autonomous cybersecurity agents, including durable workflow execution, tool and connector frameworks, safe-change pipelines, tenant isolation, ETL, GraphQL services, observability, audit trails, and distributed systems. Partner with AI researchers and security engineers to productionize agent capabilities across customer environments while enforcing authorization, rollback, quotas, and data protection.

Design, build, and operate scalable backend services for payments, cards, spend management, and compliance. Develop production-quality services and APIs, optimize databases, integrate AI and third-party APIs, and implement secure event-driven architectures. Own features from design through deployment and monitoring, contribute to reliability and CI/CD improvements, participate in on-call rotations, and collaborate with globally distributed engineering, product, compliance, and data teams.

Design and develop scalable backend systems using Kotlin, Micronaut, and Spring. Build RESTful APIs, optimize PostgreSQL and Elasticsearch databases, implement RabbitMQ-based asynchronous processing, integrate AI tools, and create automated tests. Deploy and monitor services on GCP using Docker, Kubernetes, and Terraform. Collaborate cross-functionally, participate in code reviews, troubleshoot performance issues, and deliver reliable backend products.

Design, build, and maintain backend services and APIs using Ruby on Rails. Improve performance, scalability, reliability, and write well-tested production code. Collaborate with Product, Frontend, Data Engineering, and QA teams.

Design, build, test, and support EPIC integration solutions across the full interface lifecycle. Gather requirements, resolve integration issues, develop standards and documentation, and provide production support within a remote, volunteer, part-time setup.

Develop and maintain scalable Java backend systems using Spring Boot and microservices architecture. Collaborate with customer teams, review specifications, write clean code, participate in code reviews, document solutions, and troubleshoot and optimize backend performance, reliability, and security. The role also contributes technical expertise to training next-generation AI systems, though prior AI experience is not required.

Design, develop, and maintain scalable, high-performance backend and middleware services on the JVM using Java and Spring/Spring Cloud. Build and enhance microservices, work with AWS and Docker, implement SQL/noSQL solutions (MySQL, Elasticsearch), use Git-based source control and JIRA, collaborate across engineering, design, and QA, and mentor teammates while following best practices and Agile methodologies.

Build and maintain backend services and APIs, write unit tests, debug and optimize systems, support migration from Supabase to cloud, improve reliability, and integrate AI/RPA workflows while learning under senior mentorship.

Lead backend development to scale and harden API infrastructures, implement unit testing playbooks, optimize core algorithms, support migration from Supabase to a robust cloud provider, ensure system reliability and scalability, collaborate with frontend and DevOps, and integrate AI workflows and RPA where applicable.

Build and maintain scalable backend services, RESTful and GraphQL APIs, database schemas, and cloud infrastructure. Own architecture decisions, optimize performance and reliability, improve CI/CD practices, collaborate across product and engineering teams, lead architecture sessions, review code, and mentor junior developers.

Design, develop, test, and maintain backend services and APIs for secure fintech and crypto products. Collaborate with engineering and product teams on architecture, code reviews, system design, and deployment using Azure. Optimize backend performance and scalability, resolve defects, follow DevOps and CI/CD practices, and build reliable systems supporting payments, transfers, and other financial activity.

Designs and builds secure, scalable distributed backend systems using Python and AWS. Responsibilities include event-driven architectures, asynchronous processing, cloud data pipelines, serverless applications, REST APIs, performance optimization, authentication, and cloud security. The role requires strong distributed systems, testing, debugging, and backend development expertise, with GenAI, LLM, RAG, and vector database experience preferred.

Build and operate Java-based distributed microservices supporting trade clearing, margin, settlement, reconciliation, and related financial workflows. Responsibilities include designing services, optimizing PostgreSQL, ensuring data integrity, creating tests and observability, defining service-level objectives, contributing to architecture decisions, and participating in production on-call support. The role requires full software lifecycle ownership and collaboration with nontechnical partners in a regulated clearinghouse environment.

Build and operate Java microservices supporting trade clearing, margin, settlement, reconciliation, and financial data integrity. Responsibilities include PostgreSQL optimization, distributed systems development, testing, observability, SLOs, production support, architecture documentation, and on-call ownership. The role collaborates with nontechnical partners and uses technologies including Kubernetes, Kafka, Linux, GitHub Actions, Helm, ArgoCD, and PostgreSQL.

Build and operate Java microservices supporting clearing workflows such as trade processing, margin, and settlement. Responsibilities include optimizing PostgreSQL, ensuring data integrity and reconciliation, implementing observability and service-level objectives, contributing to architecture documentation, testing, production support, and on-call operations. The role requires distributed-systems experience, strong Java skills, and collaboration with nontechnical partners.

Build and review end-to-end product features while leading backend and platform architecture. Own data models, PostgreSQL schemas, migrations, third-party integrations, CI/CD, infrastructure, monitoring, security, privacy, and outage response. Collaborate across product, design, marketing, and data teams, and help develop AI-assisted coding workflows. This individual contributor role requires strong backend depth, startup production ownership, technical communication, and a willingness to solve varied problems across web and mobile surfaces.

Build and operate reliable backend systems for complex government and enterprise data integrations. Responsibilities include designing bidirectional integrations, asynchronous workflows, retries, idempotency, observability, operational automation, debugging production systems, and creating reusable reliability patterns. The role involves TypeScript and Node.js development, database work, partner collaboration, mentoring, and improving support efficiency in a fully remote environment.

Own and maintain the WordPress platform end-to-end: hosting, security, performance, technical SEO, tracking (GA4/GTM), integrations (HubSpot/APIs), backups, and documentation. Establish environments, deployment workflows, monitoring, and runbooks while partnering with front-end and marketing teams to ensure reliable, high-performing, and compliant site operations.

Build scalable backend services and infrastructure for mobile and web products. Design secure RESTful APIs, architect high-performance systems, apply engineering best practices, estimate and track Agile tasks, mentor teammates, collaborate with clients and engineers, and take ownership of technical solutions.