Lead Python Developer

Cynet Systems•Seattle, WA

About The Position

We are seeking a Lead Python Developer to design, develop, enhance, and support modular Python services and REST APIs for our calculation engine. This role involves translating complex formulas and business rules into accurate, maintainable, and testable Python components. You will be responsible for developing and integrating calculation capabilities for various functions, building reusable libraries, and optimizing performance for global usage. The position requires strong collaboration, participation in agile ceremonies, and implementation of production-grade support procedures.

Requirements

Minimum 5+ years of professional Python development experience delivering secure, scalable, and production-quality backend applications or calculation services.
Strong proficiency in modern Python, object-oriented design, modular architecture, reusable libraries, type validation, dependency management, and coding standards such as PEP 8.
Hands-on experience developing REST APIs using FastAPI or an approved equivalent framework, including request validation, API versioning, authentication, structured error responses, and OpenAPI documentation.
Strong knowledge of SQL and PostgreSQL, including data modelling, queries, functions, indexing, transaction management, and performance optimization.
Proven ability to identify opportunities for engineering automation and productivity improvements using AI, Generative AI, intelligent agents, scripting, and developer tooling.
Experience with Pydantic, PyTest, importlib, caching, configuration management, and development of reusable Python utilities and packages.
Experience translating complex formulas, business rules, dependency graphs, or scientific models into deterministic, traceable, and testable software components.
Experience designing automated unit, integration, regression, and API tests, with disciplined defect analysis and test evidence.
Experience with Microsoft Azure services, App Service or approved container platforms, Azure DevOps, continuous integration and deployment pipelines, secrets management, logging, monitoring, and application support.
Strong understanding of secure software development, data protection, auditability, resilience, performance, and production support practices.
Strong verbal and written communication skills.
Excellent communication and presentation skills.
Ability to communicate effectively with stakeholders.

Nice To Haves

Working knowledge of building science, energy and water efficiency, materials, embodied carbon, cost calculations, or sustainability standards is preferred.

Responsibilities

Design, develop, enhance, and support modular Python services and REST APIs for the calculation engine.
Translate validated building science formulas, rules, assumptions, and dependency flows into accurate, maintainable, and testable Python components.
Develop and integrate calculation capabilities for energy, water, materials, embodied carbon, baseline standards, scenario simulation, explainability, anomaly management, and cost-related functions.
Build reusable calculation libraries, data models, validation rules, configuration services, and version-controlled datasets using Python, FastAPI, Pydantic, SQL, and PostgreSQL.
Integrate calculation services with the application through well-defined API contracts, structured inputs and outputs, secure authentication, and reliable error handling.
Optimize calculation performance, database queries, caching, asynchronous processing, and service scalability for global usage and high-volume calculation scenarios.
Create and maintain automated unit, integration, regression, and API tests using PyTest or approved equivalent frameworks.
Maintain technical documentation, API specifications, calculation traceability, data dictionaries, setup guides, deployment notes, and support runbooks.
Participate in solution design, code reviews, backlog refinement, sprint ceremonies, release planning, deployment, defect resolution, and post-deployment support.
Implement production-grade logging, monitoring, auditability, exception handling, retries, configuration management, and operational support procedures.