Senior Python Backend – Transaction Monitoring (Remote)

Crystal Intelligence; Warszawa; On-site; PLN 386,764 - 558,659; Full time

Benefits offered by this job

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Claude Code

Job summary

Crystal Intelligence is seeking a Senior Python Engineer to join the Nexus squad, focused on transaction monitoring and exploration on the Crystal platform. This fully remote role welcomes applicants across Europe and aims to streamline clients’ operations and investigations.

You will own backend services, design robust features, and collaborate with cross-functional teams to deliver scalable, production-ready code with emphasis on quality and observability.

Qualifications

• 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.

Responsibilities

• Own the transaction monitoring part of the Crystal platform.
• Improve stability and observability of the owned services.
• Maintain code to high-quality standards.
• End-to-end feature design and implementation.
• Code, debug, test and deliver features in a continuous manner.
• Provide code reviews and feedback to team members.
• Optimize performance, including database queries.
• Refactor code as necessary.

Skills

Python backend

Software architecture

SQL/NoSQL databases

PostgreSQL

Testing principles

Client-facing

Distributed systems

Product mindset

English

Tools

Redis

RabbitMQ

Kubernetes

AWS

Hetzner

Flask

Job description

Crystal Intelligence is seeking a Senior Python Engineer to join the Nexus squad, focused on transaction monitoring and exploration on the Crystal platform. This fully remote role welcomes applicants across Europe and aims to streamline clients’ operations and investigations.

You will own backend services, design robust features, and collaborate with cross-functional teams to deliver scalable, production-ready code with emphasis on quality and observability.