Senior Software Engineer

EuroPython; Kraków; Hybrid; PLN 224,000 - 336,000; Full time

Job summary

ActiveCampaign is expanding its Poland office in Krakow and inviting a seasoned backend engineer to join our Platform & AI Development team. You will build and modernize SaaS backend services using PHP and Python, scale databases like MySQL, DynamoDB and Redis, and contribute to AI workflows and partner tooling while collaborating with Product, Design, and other engineering squads.

This role offers the opportunity to help shape the architecture of our platform and deliver scalable, reliable

Qualifications

• 4+ years of work experience in a backend software engineering role.
• Experience writing production code in PHP following accepted coding standards.
• Experience with Python for backend services or AI workflows.
• Familiarity with DB technologies: MySQL, DynamoDB, Redis.
• Strong problem-solving skills and ability to work across multiple codebases and technologies.

Responsibilities

• Build and enhance backend features across the Agency platform with PHP and Python services.
• Scale SaaS systems and design scalable, configurable partner tooling and API services.
• Implement LLM-powered capabilities and AI workflows for partner experiences.
• Participate in cross-functional collaboration with Product, Design, and other engineering squads; on-call rotation.

Skills

Backend development

PHP

Python

MySQL

DynamoDB

Redis

SaaS scalability

Code quality

Collaboration

Tools

CI/CD

AWS

API design

Platform development

Job description

• Agency Platform & AI Development Building and enhancing features across the Agency platform including partner tooling, multi-account management, and API services in PHP Designing and implementing agentic AI workflows that automate and enhance partner and reseller experiences Integrating LLM-powered capabilities into core Agency features — from intelligent recommendations to automated partner operations Contributing to our Python-based AI agent development and iteration Driving productization — evolving Agency features to be more scalable and configurable for diverse partner needs Maintaining and evolving legacy codebases while driving modernization efforts
• Collaboration Working with cross-functional teams including Product, Design, and other engineering squads Engaging in pairing and code reviews Participation in the on-call rotation for incidents

Requirements

• 4+ years of work experience in a backend software engineering role
• Demonstrated knowledge of the challenges of scaling SaaS systems
• Experience writing production code in PHP following accepted coding standards
• Experience with Python for backend services or AI/agentic workflows
• Familiarity with DB technologies: MySQL, DynamoDB, Redis
• Strong problem-solving skills and ability to work across multiple codebases and technologies

Nice-to-Haves

• Experience building or integrating AI/ML systems, LLM-powered features, or agentic workflows
• Deeper database expertise — query optimization, data modeling, schema design, or experience with data pipelines and analytics infrastructure
• Familiarity with CI/CD practices and patterns
• Knowledge of AWS (or any public cloud)
• Experience with API design and platform/partner ecosystem development
• Track record of identifying and delivering performance improvements in production systems
• Experience with SaaS productization

Compensation: zł 224,000 - 336,000 (per year salary)

This is an exciting time to join ActiveCampaign as we build out our new office in Poland. You will be a large part of developing our office culture in this new Krakow hub location.