Freelance Full Stack Developer React Python Jobs in Washington, DC

Senior Full-Stack Developer (React + Python)

JOB SUMMARY

Covalent Solutions (Covalent) is seeking a mission driven, highly motivated and collaborative Senior Full-Stack Developer (React + Python) with expertise in React and Python to build modern, scalable web applications. The ideal candidate will have strong front-end skills in React combined with hands-on experience developing back-end APIs, managing databases, and deploying applications in the cloud. This role requires versatility across the full stack, with the ability to design, develop, and optimize both client-facing and server-side solutions. There will be a strong focus on application design and technology decision-making.

This opportunity is full-time with Covalent and is ON-SITE in Bethesda, Maryland.

DUTIES AND RESPONSIBILITIES include, but are not limited to:

• Develop responsive, user-friendly front-end applications using React and modern UI frameworks.
• Build and maintain RESTful APIs and backend services using Python (Django, Flask, or FastAPI).
• Design and optimize relational (PostgreSQL, MySQL) and NoSQL (MongoDB, Cosmos DB, etc.) databases.
• Integrate React front ends with Python APIs and databases to deliver seamless applications.
• Implement secure, scalable, and high-performing application architectures.
• Collaborate with DevOps on CI/CD pipelines, containerization (Docker, Kubernetes), and cloud hosting (Azure, AWS, or GCP).
• Conduct code reviews, write automated tests, and troubleshoot across the stack.
• Partner with UX/UI designers, QA, and product owners in Agile/Scrum teams.
• This position requires not just expertise in React and Python, but also the ability to critically evaluate and decide on the most effective software products, frameworks, and architectural patterns for long-term project success and scalability.

QUALIFICATIONS

Education

• Bachelor’s or Master’s in Information Technology, Computer Science, Computer Engineering or Electrical Engineering

Work Experience

• 8+ years professional software development experience.
• 6+ years building applications with React (state management with Redux or Context API).
• Strong experience with Python frameworks (Django, Flask, or FastAPI).
• Proven ability to design, build, and consume RESTful APIs (GraphQL a plus).
• Solid database experience with both SQL and NoSQL systems.
• Experience deploying applications on cloud platforms (Azure, AWS, or GCP).
• Familiarity with containerization (Docker, Kubernetes).
• Exposure to CI/CD pipelines and DevOps practices.
• Understanding of security best practices (OAuth, JWT, role-based access control).
• Prior experience working in Agile/Scrum environments.
• Proficiency with HTML5, CSS3, and modern styling frameworks (Tailwind, Material-UI, etc.).
• Experience with unit/integration testing frameworks (Jest, PyTest, etc.).
• Have led the design and implementation of application architecture from the ground up, ensuring solutions are scalable, resilient, and align with business objectives.
• Contributed to and influenced architectural strategy and modernization roadmaps across technology and business leadership.
• Evaluated and selected the most effective tools, frameworks, and services for new projects, justifying technical decisions and performing design reviews for clarity and technical merit.
• Served as a technical mentor and guide for mid-level and junior developers, providing hands-on coding support and reference code.

COMPETENCIES

Professionalism:

• Strong problem-solving and analytical abilities.
• Sharp eye for detail.
• Proven ability to manage multiple tasks concurrently and in different phases of work at the same time. Flexibility and adaptability to perform in a fast paced and dynamic environment. Context-switching does not bother you.
• Effectively collaborates and influences people at all levels in the organization through strong interpersonal and communication skills.
• Highly organized with strong time-management skills.
• Ability to manage conflict and drive resolution.
• Focused on results, proactive, service oriented
• Can focus on both high level and detail level, knowing which is appropriate for the situation.
• Ability to self-direct and manage ambiguity.
• Ability to take in a lot of disparate information and find common themes, recommend clear paths forward and iterate.
• Motivated by professional rather than personal concerns.
• Show persistence when faced with difficult problems or challenges.
• Naturally curious about things you don't understand and actively look for opportunities to grow and learn from those around you.

Communication:

• Excellent collaboration and communication skills.
• Actively participate in meetings and be willing to advocate for what you believe in. Provide thoughtful, constructive review of others’ work, knowing that everyone is working towards the same objective.
• Superior written and verbal communication skills. You can always articulate the "why" behind your solutions.
• Listen to others, correctly interpret messages from others and respond appropriately.
• Ask questions to clarify, and exhibit interest in having two-way communication.
• Tailor language, tone, style and format to match the audience.
• Demonstrate openness in sharing information and keeping people informed.
• Speak intelligently about a wide variety of topics but know when to say, "I don't know."

Teamwork:

• Self-starter who thrives in fast-paced, team-oriented environments.
• Work collaboratively with colleagues to achieve organizational goals.
• Place team agenda before personal agenda.
• Support and act in accordance with the final group decision, even when such decisions may not entirely reflect your own position.
• Share credit for team accomplishments and accept joint responsibility for team shortcomings.

Accountability:

• Take ownership of all responsibilities and honor commitments.
• Deliver outputs for which you have responsibility within prescribed time, cost and quality standards.
• Operate in compliance with organizational regulations and rules.
• Take personal responsibility for your own shortcomings, where applicable.