Senior Python Engineer

What the role needs

• This is an onsite position located in Washington, DC .
• This position is onsite in Washington, DC . Team members are expected to work from the designated office location and collaborate closely with cross-functional teams throughout the product development lifecycle.
• Backend Development & Calculation Services
• Design, develop, enhance, and maintain modular Python services and REST APIs supporting the EDGE V4 Calculation Engine.
• Translate validated formulas, business rules, assumptions, and dependency flows into accurate, maintainable, and testable software components.
• Develop calculation capabilities supporting: • Energy Modeling
• Water Efficiency
• Materials Analysis
• Embodied Carbon Calculations
• Baseline Standards
• Scenario Simulations
• Explainability Functions

From the employer

Role Overview Cognizant is seeking a highly skilled Senior Python Backend Engineer to support the development of the EDGE V4 Calculation Engine . This role will focus on designing, developing, enhancing, and maintaining scalable Python-based calculation services, APIs, and supporting platforms that deliver accurate, explainable, and high-performance sustainability calculations. The successful candidate will work closely with product owners, architects, building science specialists, quality engineering teams, and DevOps professionals to translate complex business rules, formulas, and scientific models into reliable, maintainable, and production-ready software solutions. This is an onsite position located in Washington, DC . Work Model This position is onsite in Washington, DC . Team members are expected to work from the designated office location and collaborate closely with cross-functional teams throughout the product development lifecycle. Key Responsibilities Backend Development & Calculation Services • Design, develop, enhance, and maintain modular Python services and REST APIs supporting the EDGE V4 Calculation Engine. • Translate validated formulas, business rules, assumptions, and dependency flows into accurate, maintainable, and testable software components. • Develop calculation capabilities supporting: • Energy Modeling • Water Efficiency • Materials Analysis • Embodied Carbon Calculations • Baseline Standards • Scenario Simulations • Explainability Functions • Anomaly Management • Cost Calculations • Build reusable libraries, frameworks, and utilities that enable scalable and consistent development practices. API & Platform Engineering • Design and develop secure RESTful APIs using Python and FastAPI. • Implement robust API contracts, structured request/response models, authentication mechanisms, and error-handling frameworks. • Develop reusable data models and validation frameworks using Pydantic and related technologies. • Integrate backend services with enterprise applications and external platforms through scalable interfaces. Database & Data Management • Design and optimize PostgreSQL databases supporting high-volume calculations and data processing. • Develop efficient SQL queries, stored procedures, and data models. • Implement indexing, transaction management, caching, and performance optimization strategies. • Maintain version-controlled datasets and configuration-driven business logic. Performance Optimization & Scalability • Improve application performance through: • Query Optimization • Caching Strategies • Asynchronous Processing • Scalable Service Architectures • Design solutions capable of supporting global user populations and high-volume calculation workloads. • Monitor and enhance overall system reliability, responsiveness, and throughput. Testing & Quality Engineering • Develop and maintain: • Unit Tests • Integration Tests • Regression Tests • API Tests • Utilize PyTest and related frameworks to ensure code quality and application reliability. • Support system integration testing and user acceptance testing activities. • Perform defect analysis, troubleshooting, and root cause investigations. Documentation & Technical Governance • Create and maintain: • Technical Documentation • API Specifications • Calculation Traceability Documentation • Data Dictionaries • Deployment Guides • Operational Runbooks • Ensure solutions meet documentation, auditability, and maintainability standards. • Participate in architecture reviews, code reviews, and technical design discussions. DevOps & Production Support • Contribute to CI/CD pipelines and deployment automation processes. • Implement logging, monitoring, alerting, auditability, and operational support processes. • Support release planning, deployment activities, production issue resolution, and post-deployment support. • Manage application configurations, secrets management, and operational readiness. AI & Engineering Productivity • Identify opportunities to improve engineering productivity using: • Artificial Intelligence • Generative AI • Intelligent Agents • Automation Tools • Developer Productivity Solutions • Develop practical automation solutions that improve code quality, accelerate testing, reduce manual effort, and enhance team effectiveness. • Support innovation initiatives that leverage emerging technologies to improve software delivery outcomes. Required Qualifications • Bachelor's degree in Computer Science, Engineering, Information Technology, Mathematics, or a related discipline, or equivalent experience. • Minimum 8 years of professional Python development experience delivering enterprise-grade backend applications and services. • Strong expertise in: • Python • Object-Oriented Programming • Modular Architecture • Software Design Patterns • Dependency Management • PEP 8 Coding Standards • Hands-on experience developing REST APIs using: • FastAPI • OpenAPI/Swagger • API Authentication • Request Validation • Versioning Strategies • Strong experience with: • SQL • PostgreSQL • Data Modeling • Query Optimization • Indexing • Transaction Management • Experience with: • Pydantic • PyTest • Importlib • Caching Frameworks • Configuration Management • Proven ability to translate complex formulas, scientific calculations, and business logic into deterministic software components. • Experience building automated testing frameworks and test automation solutions. • Knowledge of secure software development principles and production support best practices. • Strong analytical, documentation, troubleshooting, and problem-solving skills. Preferred Qualifications • Experience with Microsoft Azure, including: • Azure App Services • Azure DevOps • CI/CD Pipelines • Application Monitoring • Secrets Management • Experience working with containerized platforms and cloud-native architectures. • Familiarity with: • Building Science • Energy Efficiency Modeling • Water Efficiency Programs • Sustainability Standards • Carbon Accounting • Embodied Carbon Calculations • Experience implementing AI-assisted software development and engineering automation initiatives. • Exposure to sustainability technologies, environmental analytics, or green building certification programs. • Experience working within globally distributed Agile development teams. Technical Expertise Candidates should demonstrate experience in: • Python Development • FastAPI • REST API Design • PostgreSQL • SQL Optimization • Pydantic • PyTest • Azure Cloud Services • Azure DevOps • CI/CD Pipelines • Application Performance Optimization • Software Architecture • Automated Testing • Engineering Automation • Generative AI • Microservices Development • Sustainability Calculations • Production Support & Operations Salary and Other Compensation The annual salary for this position is anticipated to be between $125,000 and $145,000 USD , depending on experience, qualifications, geographic location, and other factors permitted by law. In addition to base salary, this position may be eligible for: • Annual performance-based bonus • Merit-based compensation increases • Employee referral bonuses, where applicable The compensation information provided is accurate as of the date of this posting. Cognizant reserves the right to modify compensation information based on business needs and applicable laws. Benefits Cognizant offers a comprehensive benefits package, including: • Medical, Dental, and Vision Insurance • Health Savings Account (HSA) and Flexible Spending Accounts (FSA) • Life Insurance and AD&D Coverage • Short-Term and Long-Term Disability Insurance • Paid Time Off (PTO) and Company Holidays • 401(k) Plan with Company Contributions (subject to eligibility) • Employee Stock Purchase Plan (where available) • Employee Assistance Program (EAP) • Parental Leave and Family Care Benefits • Tuition Reimbursement and Professional Development Programs • Access to Learning, Certification, and Career Development Opportunities Benefits are subject to eligibility requirements and plan terms. Why Cognizant • Build innovative solutions supporting sustainability and environmental impact initiatives. • Work on large-scale, cloud-native applications used globally. • Collaborate with architects, engineers, domain specialists, and technology leaders. • Gain exposure to cutting-edge technologies, AI-driven engineering practices, and modern cloud platforms. • Access ongoing technical training, certifications, and career advancement opportunities. • Join a global organization committed to innovation, engineering excellence, and meaningful business outcomes. Equal Opportunity Employer Cognizant is an equal opportunity employer. We are committed to fostering an inclusive workplace where all associates feel valued, respected, and empowered to contribute their unique perspectives. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, national origin, disability, protected veteran status, or any other characteristic protected by applicable law. Applications will be accepted until the position is filled. Additional employment information Compensation information is accurate as of the date of this posting. Cognizant reserves the right to modify this information at any time, subject to applicable law. Applicants may be required to attend interviews in person or by video conference. In addition, candidates may be required to present their current state or government issued ID during each interview. Cognizant is an equal opportunity employer. Your application and candidacy will not be considered based on race, color, sex, religion, creed, sexual orientation, gender identity, national origin, disability, genetic information, pregnancy, veteran status or any other characteristic protected by federal, state or local laws. Applicants for US based positions must be currently authorized to work for any employer in the United States. The company is unable to provide employment-based immigration sponsorship for US based positions. If you have a disability that requires reasonable accommodation to search for a job opening or submit an application, please email CareersNA2@cognizant.com for roles based in the Americas or CareersIndia2@cognizant.com for roles based in India. About Cognizant: Cognizant (Nasdaq: CTSH) is an AI Builder and technology services provider, bridging the gap between AI investment and enterprise value by building full-stack AI solutions for our clients. Our deep industry, process and engineering expertise enables us to build an organization’s unique context into technology systems that amplify human potential, drive tangible outcomes and keep global enterprises ahead in a fast-changing world. See how at cognizant.ai or @cognizant.