Senior Go Engineer (LangChain & ML)

LOCATION:
Remote: Spain / Portugal / Romania / Poland
ABOUT THE ROLE

We are looking for a Senior Go Engineer with a passion for high-performance systems and Generative AI. In this role, you will be responsible for building the robust backend infrastructure that powers our AI initiatives. You will leverage Go for its concurrency and speed while integrating advanced LLM workflows via LangChain. A critical part of your role will be ensuring the reliability and quality of these AI systems by utilizing LangSmith for debugging, testing, and monitoring.

‍ABOUT THE CLIENT

Our customer is an innovation-driven organization leveraging Google Cloud to revolutionize their industry through AI. They focus on moving beyond "proof of concept" AI into production-grade tools. By combining GCP’s Langchain ecosystem, they are building scalable, secure, and highly intelligent applications that solve real-world logistical and data challenges.

Who are we looking for?

RESPONSIBILITIES
Backend Development: Develop and maintain high-performance microservices using Go, focusing on clean code, concurrency, and low-latency API responses.
AI Implementation: Build and optimize LLM chains and autonomous agents using LangChain (Go or Python-bridged) to automate complex tasks.
Observability & Evaluation: Use LangSmith to trace AI executions, debug complex "chain" logic, and create evaluation datasets to ensure model accuracy and safety.
Data Engineering: Work with pgvector or GCP Matching Engine to implement efficient Retrieval-Augmented Generation (RAG) workflows.
CI/CD & Quality: Participate in building automated pipelines that include AI-specific testing (evals) to prevent regressions in model behavior.
Collaboration: Work closely with the Product Owner to transition requirements into production-ready Go services.
Engage with stakeholders to translate business requirements into robust technical solutions.
QUALIFICATIONS
Experience: 5+ years in software engineering, with at least 3+ years of professional experience building and scaling applications in Go.
AI Frameworks: Hands-on experience with LangChain and a deep understanding of the LangSmith ecosystem for monitoring and debugging LLM applications.
Cloud Expertise: Strong proficiency in Google Cloud Platform (GCP), Cloud Run, GKE, and Cloud Functions.
Database Skills: Experience with relational databases and Vector Search extensions (like pgvector) for storing and retrieving high-dimensional embeddings.
Testing & Quality: Experience building unit and integration tests for non-deterministic AI outputs.
WOULD BE A PLUS:
Python Proficiency: Ability to read and write Python to collaborate with Data Science teams and utilize the broader ML ecosystem.
Industry Experience: Background in logistics, delivery, or complex resource management systems.
Messaging: Experience with Google Pub/Sub for building event-driven architectures.
Frontend Basics: Familiarity with React to better understand how backend AI responses are consumed by the UI.

What we offer

WORK:
Flexible working hours;
Collaborative, friendly team environment;
Remote/Hybrid work;
LIFE:
Company social events;
Annual corporate parties;
HEALTH:
Comprehensive medical insurance;
EDUCATION:
Allowances for professional education;
English language courses with native speakers;
Internal knowledge-sharing sessions.

About Proxet

Proxet is a professional software development firm trusted by clients from around the world. With our expertise in AI and machine learning, we help businesses reimagine their possibilities and transform ideas into tangible digital solutions. By providing core services with an emphasis on data practices, we shape the future, one step at a time.