Senior Software Engineer — Remote AI Infra & Growth

Cello; Warszawa; On-site; PLN 240,000 - 420,000; Full time

Job summary

Cello is hiring a Senior Backend Engineer in Warsaw. You will work across frontend widgets, backend infrastructure, and data pipelines, shaping architecture and product direction. The role emphasizes shipping features rapidly while adopting AI improvements to accelerate delivery.

We value deep backend experience with NestJS or Python, TypeScript/JavaScript fluency, and hands-on AWS. Strong observability, ownership, and collaboration are essential for success.

Qualifications

• Deep backend experience with NestJS or Python and hands-on AWS knowledge running services in production.
• Fluent in TypeScript and JavaScript.
• Experience treating infrastructure as code (Terraform or similar).
• Strong opinions about observability, OpenTelemetry, distributed tracing, structured logging, dashboards and alerting.
• Know when “good enough” is adequate and when to invest in quality.
• Strong problem solver, able to break down complex, ambiguous problems and ship pragmatic solutions.

Responsibilities

• Work on frontend widgets, backend infrastructure, and data pipelines.
• Build new features and improve existing systems, shaping architecture and product direction.
• Collaborate with stakeholders with no walls, no ticket factory.
• Adopt the latest AI improvements to accelerate building and shipping.
• Influence architecture and product direction.

Skills

Backend development

TypeScript/JavaScript

Observability

Problem solving

Ownership

Communication

Curiosity

AWS production

Tools

Terraform

React

Next.js

OpenTelemetry

Job description

Cello is hiring a Senior Backend Engineer in Warsaw. You will work across frontend widgets, backend infrastructure, and data pipelines, shaping architecture and product direction. The role emphasizes shipping features rapidly while adopting AI improvements to accelerate delivery.

We value deep backend experience with NestJS or Python, TypeScript/JavaScript fluency, and hands-on AWS. Strong observability, ownership, and collaboration are essential for success.