Python Developer

Dexian DISYS; Washington (District of Columbia); On-site; USD 130,000 - 180,000; Full time

Job summary

Dexian seeks a technically strong Python backend developer for an on-site role in downtown Washington, DC. You will design, develop, and optimize modular Python services and REST APIs using FastAPI, Pydantic, and PostgreSQL, while aligning with product goals.

You will participate in solution design, code reviews, and release planning, ensuring production-grade logging, security, and reliable operation for global, high-volume calculations.

Qualifications

• 8+ years of professional Python development delivering backend services.
• Proficient in REST API design with FastAPI and OpenAPI documentation.
• Strong SQL/PostgreSQL knowledge including data modelling and indexing.
• Experience with Azure DevOps, CI/CD pipelines, and cloud deployment.
• Ability to translate complex formulas and rules into deterministic software.

Responsibilities

• Design, develop, enhance, and support modular Python services and REST APIs.
• Translate building science formulas and rules into Python components.
• Develop calculation capabilities for energy, water, embodied carbon, and cost functions.
• Build reusable libraries, data models, and version-controlled datasets.
• Integrate services through secure API contracts and robust error handling.
• Optimize performance, queries, caching, and asynchronous processing.
• Create automated tests (unit/integration/API) and support system tests.
• Maintain documentation, API specs, and runbooks.
• Participate in solution design, code reviews, and release planning.

Skills

Python development

REST API design

SQL & PostgreSQL

OpenAPI docs

Azure DevOps / CI/CD

Code quality (PEP8)

Unit testing (PyTest)

Agile delivery

AI / automation tooling

Education

Bachelor's degree in Computer Science or related

Tools

FastAPI

Pydantic

PyTest

OpenAPI

Azure

PostgreSQL

Job description

This role requires 5 days on site in downtown Washington, DC.

Seeking a technically strong candidate with a solid understanding of the full application development lifecycle, from development through production, who can clearly articulate their hands‑on experience and bring innovative ideas to the team.

Position Summary:

• Design, develop, enhance, and support modular Python services and REST APIs.

• 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 as prioritized by the product backlog.

• Build reusable calculation libraries, data models, validation rules, configuration services, and version‑controlled datasets using Python, FastAPI, Pydantic, SQL, and PostgreSQL or approved equivalent technologies.

• Integrate calculation services 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; support system integration testing and user acceptance testing.

• 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.

SKILLS / EXPERIENCE REQUIRED

• Minimum 8 years of professional Python development experience delivering secure, scalable, and production‑quality backend applications or calculation services.

• Strong proficiency in moder 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 delivering practical solutions that reduce manual effort, improve code quality, accelerate testing, and enhance team effectiveness.

• 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.

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

• Ability to collaborate with product owners, architects, building science specialists, quality assurance teams, user experience teams, DevOps teams, and business stakeholders.

• Excellent analytical, documentation, communication, and problem‑solving skills, with experience working in Agile and multicultural delivery teams across time zones.

Dexian stands at the forefront of Talent + Technology solutions with a presence spanning more than 70 locations worldwide and a team exceeding 10,000 professionals. As one of the largest technology and professional staffing companies and one of the largest minority‑owned staffing companies in the United States, Dexian combines over 30 years of industry expertise with cutting‑edge technologies to deliver comprehensive global services and support.

Dexian connects the right talent and the right technology with the right organizations to deliver trajectory‑changing results that help everyone achieve their ambitions and goals. To learn more, please visit .

Dexian is an Equal Opportunity Employer that recruits and hires qualified candidates without regard to race, religion, sex, sexual orientation, gender identity, age, national origin, ancestry, citizenship, disability, or veteran status.