Senior Software Engineer

Sowelo Consulting sp. z o.o.; Warszawa; Hybrid; PLN 260,000 - 380,000; Full time

Benefits offered by this job

Hybrid work model

Office presence in Poland

AI-forward engineering culture

Job summary

Sowelo Consulting sp. z o.o. in Poland is seeking a Senior Software Engineer to design, build, and maintain high-volume, event-driven back-end services and data pipelines for the client platform.

You will lead architectural decisions and mentor engineers while contributing end-to-end across Python and React/TypeScript, champion AI-first engineering practices, and raise team standards. You will collaborate with product, UX, and QA to translate business requirements into maintainable solutions,

Qualifications

• 6+ years of professional software engineering experience with production systems.
• Deep Python expertise for back-end services and API design.
• Strong relational database design, indexing, migrations, and performance.
• Asynchronous, event-driven experience with queues or streams.
• Cloud experience, preferably AWS; ability to work across time zones.
• Proven design and technical leadership from ambiguity to delivery.
• Experience with React/TypeScript and modern front-end work.
• Production ownership including on-call, debugging, and reliability.
• Solid engineering hygiene: Git, CI/CD, automated tests and reviews.
• Proficient English written and spoken; AI tooling familiarity welcomed.

Responsibilities

• Design, build, and own back-end services in Python powering APIs and data pipelines.
• Lead design work for non-trivial features, document decisions, and drive closure.
• Build and evolve event-driven processing and high-volume data workflows.
• Collaborate across stack including React/TypeScript to ship end-to-end features.
• Model and optimize relational data, including schema design and migrations.
• Improve reliability, participate in on-call, reduce alert noise, and resolve issues.
• Mentor mid-level engineers and raise engineering standards through code reviews.

Skills

Python back-end

Django/DRF or FastAPI

Relational databases

Asynchronous/event-driven

AWS

React/TypeScript front-end

Git/CI-CD

English proficiency

AI tooling / AI-first

Technical leadership

Tools

Kafka

PostgreSQL

Aurora/MySQL/Oracle

Celery

Job description

If you have answered yes, we are looking for you.

You could join our clients rapidly growing SaaS software company which operates on a global scale.

We are searching for a Senior Software Engineer based in Poland to design, build, and maintain high-volume, event-driven back-end services and data pipelines for our Client platform. In this role, you will lead architectural decisions, optimize relational databases, contribute end-to-end across Python and React/TypeScript, champion AI-first engineering practices, and elevate team standards through mentorship and operational excellence.

Your tasks will include:

• Design, build, and own back-end services in Python that power the platform: APIs, document workflows, and data processing pipelines


• Lead design work on non-trivial features: propose architectures, weigh trade-offs, write and review design documents, and drive decisions to closure with the team


• Build and evolve event-driven and asynchronous processing (streams, queues, scheduled jobs) supporting EDI document workflows at high volume


• Contribute across the stack including React/TypeScript front-end work so that features ship end-to-end rather than stopping at a service boundary


• Model and optimize relational data: schema design, query performance, migrations, and partitioning strategies on large production datasets


• Improve reliability and observability: participate in on-call and incident response, reduce alert noise, and drive the resolution of recurring production issues


• Raise the engineering bar through code review, pairing, and mentoring of mid-level engineers


• Partner with product management, UX, and QA to turn business requirements into maintainable solutions, and with adjacent teams on cross-service dependencies


• Work AI-first: use AI engineering tools as a default part of the delivery loop, and actively improve how the team applies them like shared tooling, prompts and skills, agentic workflows, and sensible guardrails

To be a good fit for the Senior Software Engineer role, you will have:

• 6+ years of professional software engineering experience, with demonstrable ownership of production systems


• Deep Python expertise for back-end services like Django/DRF, FastAPI, or equivalent - including API design and testing practices


• Strong relational database skills: schema design, indexing, query optimisation, and migrations (PostgreSQL/Aurora, MySQL, or Oracle)


• Asynchronous and event-driven experience: message queues or streaming (Kafka, Kinesis, SQS/SNS, RabbitMQ) and background task processing (Celery or similar)


• Cloud experience, AWS preferred (or Azure/GCP with willingness to work in AWS)


• Design and technical leadership: has driven a meaningful feature or system from ambiguous requirements through design, delivery, and operation


• Working experience with React and TypeScript or another modern component framework (Vue, Angular) plus a genuine willingness to work in React


• Production ownership: on-call participation, debugging live incidents, and improving reliability afterwards


• Solid engineering hygiene: Git, CI/CD, automated testing, code review


• Comfortable in an Agile/Scrum team and in a distributed setting across time zones


• Professional working proficiency in English, written and spoken


• Fluent, daily hands-on use of AI engineering tools (Claude, GitHub Copilot, Cursor or similar)

Reasons to join:

• Employment contract


• Modern tech stack (Python, React, TypeScript, AWS) with room to influence architectural decisions


• AI-forward engineering culture - the team actively uses Claude and Copilot in daily work, with growing opportunities to build AI-powered product features


• Hybrid work model with office presence in Poland - flexibility plus in-person collaboration


• Opportunity to work on complex data workflows (EDI, supply chain automation) that most engineers never encounter


• Collaborative, non-hierarchical engineering culture - all ideas are heard, knowledge-sharing is fast and organic, and bureaucracy is minimal