Senior Python Engineer (Remote)

Position Summary:
We are looking for a talented Senior Python Engineer to join our team responsible for transaction monitoring and exploration. This is a fully remote role, and we welcome applications from anywhere in Europe. As part of our Nexus squad, you will play a critical role in streamlining clients’ operations and smoothing their investigations on the Crystal platform.
More details: crystalintelligence.com

Duties and responsibilities:
Owning the transaction monitoring part of the Crystal platform;

Improving stability and observability of the owned services;

Maintaining code to high-quality standards;

End-to-end feature design and implementation;

Coding, debugging, testing and delivering features and improvements in a continuous manner;

Providing code reviews, assistance and constructive feedback to other team members;

Performance optimizations (including database queries optimizations);

Refactoring code as necessary.

Required:
8+ years of commercial experience developing Python backend services and APIs for the web;

Solid software architecture skills;

Strong knowledge of SQL/NoSQL databases and data architecture, including PostgreSQL;

Knowledge of testing principles at different levels of the system;

Experience in developing client-facing solutions;

Experience with distributed systems;

Product-oriented mindset;

Proficiency in English.

Would be a plus:
Experience with scalability and performance optimizations of large distributed systems.

Experience with systems operating on large data volumes;

Experience with the Flask framework;

Passion for cryptocurrencies and blockchain technologies.

No previous knowledge of Blockchain technology required.

Tech stack:
Redis, RabbitMQ, PostgreSQL, ClickHouse;

Kubernetes, AWS + Hetzner;

Python 3.14, Flask, Granian;

Datadog, Grafana.

You’ll get:

AI tool of your choice: Cursor or Claude Code.