Sr. Python Developer

Job#: 3028698

Job Description:

Sr. Software Engineer (Python/FastAPI)

Location: Plano, Texas (onsite 4 days/week)

Employment Type: Contract

Role Overview

We are seeking a Sr. Software Engineer to build, operate, and scale Python APIs and backend services that integrate AI capabilities. This role focuses on productionizing integrations, orchestrations, and data flows for internal and external applications. The ideal candidate will be a self-starter who can navigate the organization effectively and contribute to a sustainable team environment.

Key Responsibilities

• Design, implement, and document FastAPI services and SDKs for AI features.
• Integrate third-party AI providers like Google Gemini, Bedrock, and OpenAI using secure and observable patterns.
• Build and maintain event-driven and synchronous backends, including REST APIs, webhooks, and queues, with robust error handling.
• Optimize for latency, throughput, and cost by implementing caching, rate limiting, and resiliency patterns like retries and circuit breakers.
• Ship high-quality, tested code through CI/CD pipelines.
• Instrument services with structured logs, metrics, and traces to ensure production readiness.
• Collaborate with product, data, and machine learning teams to translate requirements into technical specifications.
• Uphold security, privacy, and compliance standards, including secrets management, OAuth/OIDC, and PII handling.

Required Qualifications

Experience: 8+ years of professional software engineering experience is required for this senior-level role.

Technical Skills:

• Strong proficiency in Python
• Production experience with FastAPI, delivering secure and versioned APIs.
• Cloud experience on GCP (, Cloud Run, GKE, Pub/Sub) or AWS (, Lambda, EKS, API Gateway, SQS).
• Experience with relational datastores (Postgres/MySQL) and caching stores (Redis/ElastiCache/Memorystore), including schema design and migrations.
• Familiarity with CI/CD (GitHub Actions/Cloud Build), containerization (Docker), and Infrastructure as Code (Terraform is helpful).
• A strong understanding of testing methodologies (unit, integration, contract), API specifications (OpenAPI), and observability principles.
• Familiarity with Agentic AI.

Preferred Qualifications

• Experience integrating AI services such as Vertex AI/Gemini, AWS Bedrock, or OpenAI.
• Intermediate data engineering skills with Python and SQL.
• Knowledge of security protocols like OAuth/OIDC, JWT, and service-to-service authentication.
• Familiarity with data pipeline basics and schema evolution practices.
• Experience with LangGraph is a plus.
• Front-end development experience with React is a plus.

Compensation & Benefits

A competitive compensation package is offered for this W-2 contract position.

This employer is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.

Apex uses a virtual recruiter as part of the application process. Click here for more details.

If you have visited our website in search of information on employment opportunities or to apply for a position, and you require an accommodation in using our website for a search or application, please contact our Benefits Department at or 804-523-8228.

Apex Systems is a world-class IT services company that serves thousands of clients across the globe. When you join Apex, you become part of a team that values innovation, collaboration, and continuous learning. We offer quality career resources, training, certifications, development opportunities, and a comprehensive benefits package. Our commitment to excellence is reflected in many awards, including ClearlyRated's Best of Staffing® in Talent Satisfaction in the United States and Great Place to Work® in the United Kingdom and Mexico. Apex uses a virtual recruiter as part of the application process. Click here for more details.

Apex Benefits Overview: Apex offers a range of supplemental benefits, including medical, dental, vision, life, disability, and other insurance plans that offer an optional layer of financial protection. We offer an ESPP (employee stock purchase program) and a 401K program which allows you to contribute typically within 30 days of starting, with a company match after 12 months of tenure. Apex also offers a HSA (Health Savings Account on the HDHP plan), a SupportLinc Employee Assistance Program (EAP) with up to 8 free counseling sessions, a corporate discount savings program and other discounts. In terms of professional development, Apex hosts an on-demand training program, provides access to certification prep and a library of technical and leadership courses/books/seminars once you have 6+ months of tenure, and certification discounts and other perks to associations that include CompTIA and IIBA. Apex has a dedicated customer service team for our Consultants that can address questions around benefits and other resources, as well as a certified Career Coach. You can access a full list of our benefits, programs, support teams and resources within our ‘Welcome Packet’ as well, which an Apex team member can provide.