Python Developer

O16 Labs is looking for a seasoned Senior Software Engineer with strong expertise in backend development to join their team. The successful candidate will play a key role in designing, building, and scaling high-performance backend systems using Python and modern cloud technologies. This position involves leading backend modernization projects within a collaborative and engineering-driven environment. The role is based in Karachi and follows a hybrid work model, offering flexibility while maintaining close team engagement.

Key Responsibilities
Design, develop, and maintain scalable backend systems primarily using Python, leveraging frameworks such as Django and FastAPI. Lead the migration of existing Node.js applications to Python-based frameworks, ensuring smooth transitions and improved system performance. Develop and optimize REST APIs with a focus on robust architecture and high responsiveness. Implement SQL optimization techniques and manage relational databases like PostgreSQL and MySQL using SQLAlchemy ORM. Deploy and maintain backend services on cloud platforms including AWS and GCP. Utilize containerization tools such as Docker and manage CI/CD pipelines to streamline software delivery processes. Integrate caching solutions like Redis and search technologies such as Elasticsearch to enhance system efficiency. Handle complex data processing tasks and design event-driven architectures to support scalable and resilient applications.

Required Qualifications
Candidates should have between 8 to 12 years of overall software engineering experience, with at least 5 years dedicated to backend development. Strong proficiency in Python programming is essential, along with hands-on experience in Django and FastAPI frameworks. Proven track record of migrating applications from Node.js to Python is required. A solid understanding of Pydantic for data validation and REST API design principles is necessary. Expertise in SQL query optimization and practical experience managing PostgreSQL and MySQL databases are expected. Familiarity with SQLAlchemy ORM for efficient database interactions is important. Candidates must have practical knowledge of cloud infrastructure services on AWS and GCP. Experience working with Docker containers, CI/CD pipelines, Redis caching, and Elasticsearch search engine is also required. A background in data processing, cloud database management, and event-driven system design will be highly valued.

Preferred Qualifications and Benefits
A bachelor’s degree in a relevant field is preferred but not mandatory. This role offers the opportunity to lead backend modernization initiatives and contribute significantly to large-scale system development. Candidates will gain exposure to cutting-edge cloud technologies within a dynamic and collaborative work environment. The position provides a competitive monthly salary ranging from Rs100,000 to Rs250,000. Employment is full-time with a hybrid work model based at Mega Malls & Residency, Gulistan-e-Johar, Karachi.

Applicants should be prepared to discuss their experience with Django, Flask, and FastAPI frameworks during the selection process. Only shortlisted candidates will be contacted for further evaluation.