• Design, build, and scale new features for REST APIs and large-scale data processing pipelines that handle high-volume datasets across distributed systems. • Architect and optimize backend services for high throughput and low-latency performance. • Develop data-intensive and event-driven applications using Python, Typescript, Spark, and AWS-native services. • Work with Spark, EMR, Glue, Kafka, or similar frameworks to process and transform very large datasets. • Improve system performance, reliability, and scalability across microservices and cloud infrastructure. • Partner with senior engineers, architects, DevOps, and QA throughout the full development lifecycle. • Mentor developers, guide code reviews, and raise engineering quality standards. • Automate deployments and CI/CD using Terraform, Serverless Framework, and Kubernetes-based workflows.

• Performing full‑stack development for client/server Java applications • Designing, developing, and maintaining responsive web interfaces using React • Maintaining current knowledge of relevant technologies • Generating new code and enhancing or refactoring existing code to meet requirements • Participating in the design, coding, testing, and debugging of new or existing software • Troubleshooting technical issues and providing support for application and system functions

Principal Backend Engineer|Architect Location: Chicago, IL (Hybrid – 1 day/week in-office) Contracted to Full Time Experienced Company: Ludex, Inc. About Ludex 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 Overview We 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 Responsibilities - Design, develop, and maintain scalable backend services using Node.js, NestJS, and TypeScript - Build and optimize APIs that support consumer-facing products and enterprise workflows - Design, manage, and optimize PostgreSQL databases and data models for performance and reliability - Work 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 features - Ensure high standards for code quality, efficiency, security, and performance - Identify and resolve performance bottlenecks across services and databases - Participate in architecture discussions and contribute to long-term technical strategy - Support deployments, monitoring, and system reliability in production environments - Thrive in a fast-paced startup environment, balancing speed with sound engineering judgment Required Qualifications - 7+ years of professional backend engineering experience - Strong proficiency with Node.js and TypeScript - Hands-on experience with NestJS or similar backend frameworks - Deep experience working with relational databases, particularly PostgreSQL - Proven experience building and scaling consumer-facing applications - Experience working with AWS in production environments - Strong understanding of API design, data modeling, and system architecture - Ability to write clean, efficient, maintainable, and well-tested code - Strong 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 requirements - Strong communication skills and a collaborative mindset Nice to Have - DevOps experience, including CI/CD pipelines, infrastructure-as-code, or deployment automation - Experience with system monitoring, observability, and performance tuning - Experience supporting high-scale or data-intensive applications - Prior startup or high-growth company experience Work Environment - Hybrid role: must be able to work in-office in Chicago at least 1 day per week - Collaborative, hands-on engineering culture - Small team, high ownership, and real influence on product direction Why Ludex - Build products used by millions of passionate collectors - High-impact role with real ownership and visibility - Opportunity to shape architecture and engineering standards - Fast-moving, entrepreneurial environment without heavy bureaucracy

Role Description We’re building scalable, data-driven product systems and looking for a Staff Software Developer with strong engineering skills and a track record of designing and delivering complex, production-grade systems. You’ll lead the design and delivery of critical product components, collaborate closely with technical leads and senior stakeholders, and play a key role in driving technical quality, scalability, and engineering standards across a core product area. What you’ll do - Own delivery for significant features or systems: clarify requirements, design solutions, execute, ship, and iterate. - Design and build scalable backend services, APIs, and data pipelines that support core product functionality. - Drive system design decisions, balancing scalability, performance, reliability, and cost. - Define how quality is measured for your area (success metrics, testing strategy, observability) and automate it wherever possible. - Lead structured experimentation: define hypotheses, evaluate results, and translate insights into product and system improvements. - Improve operational readiness: deployment automation, monitoring/alerting, incident response, and performance optimization. - Mentor engineers through design reviews, code reviews, and hands-on technical guidance. - Influence engineering best practices, architecture decisions, and long-term technical direction. Engineering Expectations - Strong system design skills with the ability to break down ambiguous problems into scalable technical solutions. - Ability to evaluate new technologies, tools, and approaches, and recommend solutions based on trade-offs, impact, and ROI. - Builds systems that are secure, reliable, and compliant by design, partnering with cross-functional teams when needed. - Drives technical alignment across teams and contributes to improving engineering standards and processes. How we work - We balance exploration with delivery — test ideas quickly, then productionize what works. - “Done” means quality goals are met, followed by continuous improvement in scalability, performance, and reliability. - The team owns systems end-to-end (build, release, reliability). Years of experience - Overall: 6+ years in software engineering - Relevant: 3+ years building and shipping production systems in product teams - Technical (hands-on coding): 5+ years Required skills & knowledge - Strong software engineering fundamentals and advanced system design experience - Hands-on coding in Python and/or TypeScript (or similar), building APIs, services, and data pipelines - Experience designing and scaling distributed systems in production environments - Strong experience with cloud platforms (AWS, GCP, or Azure), CI/CD, automated testing, and observability - Proven ability to own systems end-to-end, from design through production and iteration - Experience working in fast-paced, ambiguous environments with evolving requirements - Strong experimentation mindset: define metrics, build evaluation approaches, and iterate quickly Desired (nice to have) - Experience building data-driven or ML-enabled systems - Familiarity with experimentation frameworks, A/B testing, or performance optimization - Experience with event-driven architectures, streaming systems, or large-scale data processing - Exposure to modern AI tools or integrations (not required) - Contributions to open source, technical blogs, or conference talks Education - Bachelor’s in Computer Science, Engineering, or related field (or equivalent practical experience) Salary Information The expected base salary range for this role is $104,300 - $130,000 CAD and individuals may be eligible to participate in our variable compensation program. Final compensation may vary based on experience, skills, designations, and market conditions. Company Description Varicent is committed to creating a diverse environment and is proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. If you require accommodation at any time during the recruitment process please email accomodations@varicent.com.