Full Stack Software Engineer - Strong backend

Location: PECHS, Karachi, Pakistan (Onsite) - Afternoon shift

Employment Type: Full-time

Experience: 2-5 years of professional software development, including at least 1 year building AI or LLM-powered features

About the Role

Qualix Solutions builds AI-powered products, and we're looking for a mid-level engineer who is strong on the backend, hands-on with agentic AI development, and has a genuine eye for good UI. You'll work on features end to end: designing APIs and data models, orchestrating LLM-driven agentic workflows, and shipping interfaces that feel clean and intuitive. Our backend work spans both Python and Node.js/NestJS, so strength in either is a great fit.

This is a role for someone who thrives in ambiguity. Requirements won't always arrive fully formed. We expect you to ask the right questions, propose a direction, and turn vague problems into clear, working software.

What You'll Do

• Design and build backend services and REST APIs in Python (FastAPI, Django, or Flask), or Node.js (NestJS)
• Build agentic AI features: tool calling, multi-step workflows, LLM orchestration, and integrations with model APIs (Claude, OpenAI, etc.)
• Implement authentication and authorization (JWT / OAuth), input validation, and error handling
• Design database schemas and write efficient queries (PostgreSQL and/or MongoDB), including indexing and performance tuning
• Build and refine frontend features in React with attention to layout, spacing, and usability
• Take loosely defined problems, clarify scope with stakeholders, and deliver well-scoped solutions
• Debug issues across the stack and participate in code reviews
• Collaborate with designers, engineers, and product stakeholders

What We're Looking For

Backend (Strong):

• Strong proficiency in either Python (FastAPI, Django, or Flask) or Node.js/TypeScript (NestJS): REST APIs, modules/services, typing, validation, and error handling. You only need one; comfort in both is a plus
• Deep understanding of backend fundamentals: API design, authentication, caching, background jobs, error handling, and logging
• Databases: schema design, indexing, and query optimization in PostgreSQL or MongoDB
• API security: input validation, basic XSS / CSRF awareness

Agentic AI:

• Hands-on experience building agentic systems: tool use / function calling, multi-step agent workflows, and prompt design
• Experience integrating LLM APIs (Anthropic, OpenAI, or similar) into production features
• Familiarity with frameworks such as LangChain, LangGraph, or the Claude Agent SDK, or equivalent custom orchestration

Frontend and UI:

• React: hooks, functional components, state management (Redux or Zustand)
• Tailwind CSS or equivalent, responsive layouts (Flexbox, CSS Grid)
• A strong sense of good UI design: you notice bad spacing, confusing flows, and inconsistent components, and you fix them

Ways of Working:

• Comfortable working with ambiguity and driving toward clarity
• Excellent verbal and written English communication
• Problem-solving mindset and attention to detail

Nice to Have

• Next.js (SSR, SSG, API routes)
• Vector databases and RAG pipelines (e.g., pgvector, Pinecone, Weaviate)
• Docker basics and cloud exposure (AWS / Azure / GCP)
• CI/CD awareness
• Bachelor's degree in Computer Science or a related field

Job Type: Full-time

Application Question(s):

• Why do you want to switch?
• What is your current salary?
• What is your expected salary?
• Is your expected salary negotiable?
• What is your notice period?
• Rate your English speaking skills from 1 (Novice) to 10 (Expert)?

Experience:

• Development: 2 years (Preferred)

Work Location: In person