Principal Backend Engineer | ArchitectLocation: Chicago, IL (Hybrid – 1 day/week in-office) Company: Ludex, Inc.Ludex is a consumer-facing technology platform transforming the sports and trading card hobby through AI-driven scanning, data, and marketplace tools. We build products used by millions of collectors and enterprise sellers, and we move fast. If you thrive in a startup environment where ownership, velocity, and impact matter, you'll feel at home here.Role OverviewWe are seeking a hands-on Principal Engineer to help design, build, and scale the backend systems that power Ludex's consumer and Enterprise products.
This role is ideal for an experienced engineer who enjoys building high-performance, scalable applications, working close to the product, and operating with an entrepreneurial mindset.You will play a critical role in architecture decisions, performance optimization, and the evolution of our platform as we scale users, data volume, and revenue.This role requires a high level of ownership and autonomy. You will be responsible for making key backend architecture decisions and driving execution in a fast-moving startup environment.Key ResponsibilitiesDesign, develop, and maintain scalable backend services using Node.js, NestJS, and TypeScriptBuild and optimize APIs that support consumer-facing products and enterprise workflowsDesign, manage, and optimize PostgreSQL databases and data models for performance and reliabilityWork with AWS infrastructure (e.g., EC2, RDS, S3, Lambda, CloudWatch, etc.)Collaborate closely with frontend engineers, product, and other teams to deliver end-to-end featuresEnsure high standards for code quality, efficiency, security, and performanceIdentify and resolve performance bottlenecks across services and databasesParticipate in architecture discussions and contribute to long-term technical strategySupport deployments, monitoring, and system reliability in production environmentsThrive in a fast-paced startup environment, balancing speed with sound engineering judgmentRequired Qualifications7+ years of professional backend engineering experienceStrong proficiency with Node.js and TypeScriptHands-on experience with NestJS or similar backend frameworksDeep experience working with relational databases, particularly PostgreSQLProven experience building and scaling consumer-facing applicationsExperience working with AWS in production environmentsStrong understanding of API design, data modeling, and system architectureAbility to write clean, efficient, maintainable, and well-tested codeStrong ability to independently evaluate technical approaches and make architecture decisions in a startup environment.Proven experience owning backend systems end-to-end, including design, implementation, deployment, and ongoing evolution.Comfortable working in ambiguous, fast-moving environments with evolving requirementsStrong communication skills and a collaborative mindsetNice to HaveDevOps experience, including CI/CD pipelines, infrastructure-as-code, or deployment automationExperience with system monitoring, observability, and performance tuningExperience supporting high-scale or data-intensive applicationsPrior startup or high-growth company experienceWork EnvironmentHybrid role: must be able to work in-office in Chicago at least 1 day per weekCollaborative, hands-on engineering cultureSmall team, high ownership, and real influence on product directionWhy LudexBuild products used by millions of passionate collectorsHigh-impact role with real ownership and visibilityOpportunity to shape architecture and engineering standardsFast-moving, entrepreneurial environment without heavy bureaucracy