Senior Fullstack Engineer (Python+React)
Summary
Senior fullstack engineer building internal GenAI solutions for a large enterprise client: developing Python/FastAPI services and GenAI agents with LangGraph/LangChain on AWS Bedrock, plus React/Next.js frontends, backed by PostgreSQL/pgvector and Elasticsearch. A 12-month remote contract from Poland (CET) starting ASAP.
🧠 Tech Level: Senior
🗣 Language Proficiency: Upper-Intermediate
🧾 Employment type: Full time
🌍 Candidate Location: Poland
🕐 Working Time Zone: CET
🚀 Start: ASAP
🧭 Planned Work Duration: 12 months
👥 Customer Description:
Our client is a large international enterprise operating across multiple industries and regions.
🧩 Project Description:
You will work with a specialized internal business domain team focused on internal GenAI initiatives.
Soft Skills:
• Ability to manage multiple tasks and priorities effectively in parallel
• Strong critical thinking skills
• Proactive approach to clarifying requirements
• Comfortable working in a proof-of-concept-oriented delivery environment
• Excellent communication skills
💡 Hard Skills / Must Have:
• Experience with Python and FastAPI in production environments
• Practical experience with GenAI and agentic application development, with LangGraph as the primary framework and hands-on knowledge of LangChain
• Experience with managed cloud-based GenAI services such as AWS Bedrock / AgentCore or comparable solutions
• Strong experience with PostgreSQL and relational database development
• Hands-on experience with Pandas and Excel-based data processing
• Frontend development experience with Next.js and React
• Experience using AI-assisted development tools such as Cursor, Claude Code, or Codex
• Experience designing and developing scalable APIs and backend services
✨ Hard Skills / Nice to Have:
• Experience with MCP and FastMCP
• Experience with web scraping and external data ingestion
• Experience with Docker, cloud-native architectures, and serverless technologies
• Experience with Terraform and cloud infrastructure troubleshooting
📌 Responsibilities:
• Develop, test, debug, maintain, and continuously improve Python-based applications and services
• Deploy and configure applications and services in AWS environments
• Provision and manage infrastructure using Infrastructure as Code, while considering system performance and cloud costs
• Work with PostgreSQL using pg_vector or with search technologies such as OpenSearch or Elasticsearch to support vectorized custom data and Retrieval-Augmented Generation use cases
• Design and implement GenAI agents using AWS Bedrock and related cloud-based AI capabilities
• Evaluate open-source GenAI frameworks against direct API integrations with leading GenAI providers and select appropriate approaches for specific use cases
• Explore and implement multi-agent solutions using frameworks such as AutoGen where appropriate
• Investigate and resolve application, infrastructure, and integration issues, while optimizing system performance and reliability
• Collaborate with stakeholders and technical teams across multiple global regions and contribute to innovation within the broader engineering organization
🧪 Technology Stack: Python, React, Next.js, FastAPI, LangGraph, LangChain, AWS Bedrock, PostgreSQL, ElasticSearch
📞 Interview stages:
• English check (15 minutes)
• Internal technical interview (1-1,5 hour)
• Client interview (1 hour)
📝 Additional notes:
The candidate must be employed in our company at 0.125 FTE under UoP (employment contract). Payment terms — up to 60 days. Work will be performed using client-provided equipment.
📩 Ready to Join?
We look forward to receiving your application and welcoming you to our team!