Staff / Senior Staff Software Engineer – AI Systems

Location: Remote, Poland

Salary: 32,000–40,000 PLN + VAT per month on a B2B contract, or the equivalent on an employment contract

Company

CKSource builds CKEditor, an open-source rich text editor used by millions worldwide, and operates as part of hirify.global alongside TinyMCE, ButterCMS, and Uploadcare.

What you will do

• Lead the architecture and technical direction of AI-powered backend systems from exploration through production.
• Design scalable systems with appropriate APIs, service boundaries, reliability, performance, security, and cost controls.
• Turn complex product ideas into experiments, prototypes, and production-ready solutions.
• Build reliable LLM integrations and establish testing, evaluation, monitoring, and improvement practices for AI features.
• Write and review code, solve complex technical challenges, mentor engineers, and influence engineering practices without formal authority.

Requirements

• Experience designing and delivering complex production systems at Staff, Senior Staff, Tech Lead, or equivalent level.
• Strong hands-on experience with TypeScript, Node.js, software architecture, and distributed systems.
• Experience building LLM- or AI-powered features in production, including testing, evaluation, observability, and reliability.
• Strong architectural judgment and the ability to balance simplicity, scalability, and maintainability.
• End-to-end ownership of ambiguous technical challenges through production delivery.
• Ability to influence technical decisions, mentor engineers, and collaborate across teams without formal authority.

Nice to have

• Multi-provider LLM integrations, AI evaluation frameworks, tracing, or experimentation experience.
• AWS, infrastructure as code, and event-driven architecture experience.
• Experience building developer platforms, APIs, SDKs, open-source products, shared libraries, frameworks, or internal platforms.

Culture & Benefits

• Flexible schedule and the possibility to work fully remotely.
• Professional development resources, including up to 5 additional leave days and 6,000 PLN yearly.
• LinkedIn Learning access and English lessons with a native speaker.
• Extra leave for Tiugo Day and the employee’s birthday.
• Private medical care, a Multisport card, and access to mental health support.
• Contractors receive two weeks of paid parental leave.