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Senior Python Developer - W2 contract

eSolutionsFirst, LLCMcLean, VA🇺🇸United StatesPosted 30 Jul 2026

Quick Overview

Work Type
On Site
Level
Mid Senior

Job Description

Senior Python Developer   

6 Months contract –  Later Hire (CTH/C2H)

McLean , VA – On-site   M-F  / W2 Contract 

Interview Information:

Rounds: 2 rounds   /  Interview Type: MS Teams - Video Mandatory| In Person

 Must Have Qualifications:

  • 5+ years of engineering experience with at least 2 years of recent Python experience, specializing in heavy data applications.
  • Demonstrates strong data integrity skills and proficiency in c, with a proven track record of leading data-focused projects.

Job Description:

  • We are seeking an experienced Senior Python Developer to join our team.
  • The ideal candidate will have a strong background in Python development, PostgreSQL, Flask or FastAPI, and data transformation using modern data-processing frameworks.
  • You will be responsible for designing, developing, and maintaining data-intensive applications and ETL pipelines.
  • Experience with Informatica and scalable data transformation approaches is preferred.

Responsibilities:

  • Design, build, and maintain scalable Python applications for data processing and analytics.
  • Develop RESTful APIs using Flask or FastAPI.
  • Implement and optimize complex SQL queries and database structures in PostgreSQL.
  • Architect and maintain ETL pipelines using Informatica, ensuring data quality and integrity.
  • Work with large datasets, ensuring efficient data ingestion, transformation, and storage.
  • Develop and optimize data transformation workflows using PySpark.
  • Collaborate with cross-functional teams to define technical requirements and deliver solutions.
  • Troubleshoot and resolve issues in production environments.
  • Mentor junior developers and contribute to best practices.

Requirements:

  • Bachelor’s degree in computer science, Engineering, or related field (or equivalent experience).
  • 5+ years of professional experience as a Python developer.
  • 3+ years of experience with PostgreSQL, including database design and performance tuning.
  • 3+ years of experience developing APIs with Flask or FastAPI.
  • Proven experience working with large datasets and data-intensive applications.
  • Experience integrating AI or machine learning models into data pipelines or applications.
  • Familiarity with Python-based machine learning libraries such as scikit-learn, TensorFlow, or PyTorch.
  • 2+ years of experience with data transformation using PySpark, Dask, Polars, etc.
  • Strong understanding of data modeling, data warehousing, and data integration concepts.
  • Experience with version control systems (e.g., Git).
  • Excellent problem-solving skills and attention to detail.
  • Strong communication and teamwork abilities.

Preferred Qualifications:

  • Hands-on experience with Informatica and ETL processes.
  • Experience with cloud platforms.
  • Familiarity with containerization (Docker, Kubernetes).
  • Knowledge of data visualization tools and techniques.

Skills

Docker
FastAPI
Flask
SQL
ETL
Machine Learning
Scikit-learn
Git
Kubernetes
PostgreSQL
PyTorch
Python
TensorFlow

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