API Integration Engineer

Worldline; Warszawa; Hybrid; PLN 262,000 - 393,000; Full time

Benefits offered by this job

Private medical & life insurance

Public transportation allowance

Annual bonus

Job summary

Worldline is seeking an API Integration Engineer to join a dynamic technical team working across Vienna, Warsaw, Paris, Seclin, and Villeurbanne. You will drive seamless integration between internal systems and external clients, troubleshooting issues and optimizing performance in a global financial services context.

You will onboard partners, embed ECR API into partner environments, and deliver robust API solutions, with strong English communication and collaboration across distributed teams.

Qualifications

• 4–5 years of experience in a similar role, focusing on API integrations (including the ECR API).
• Master’s degree or equivalent in a relevant field.
• Excellent command of English, both spoken and written; ability to work with distributed teams.
• Experience in system integration, especially within financial services or POS/ECR environments.

Responsibilities

• Onboarding focus: Deliver a structured onboarding package comprising Documentation, Integration Kits, Kickoff Meetings, and Test Equipment.
• Collaborate with integrators and partner developers to embed Worldline’s ECR API into partner ECR environments, enabling secure payments via Terminal API and ToM.
• Produce and maintain developer documentation, sample code, tutorials, and API references; keep integration guides up to date for API product use cases.
• Advise on best practices for API usage, error handling, and monitoring partner developers to accelerate time-to-value and production readiness.
• Troubleshoot and resolve issues related to API connectivity and system interoperability.
• Provide technical support and integration assistance for projects involving API Integrations.
• Collaborate with development and QA teams to ensure robust and reliable integration solutions.
• Communicate effectively in English with clients and internal teams to relay technical information clearly.

Skills

API integration

ECR API

English communication

Team collaboration

Troubleshooting

Education

Master's degree

Job description

At Worldline, we are proud to be at the forefront of the payments technology industry, shaping how the world pays and gets paid. Our innovative solutions power the growth of millions of businesses across the globe. We are now looking for a talented API Integration Engineer to join our dynamic technical team in Vienna (Austria), Warsaw (Poland), Brussel (Belgium), Seclin (France), or Villeurbanne (France), helping us support and improve our cutting-edge integrations, with a focus on next-generation API integrations — essential components of financial services (for example, Tap on Mobile (ToM) and Terminal API).

The Opportunity

Join us as an API Integration Engineer and become a key player in ensuring seamless communication between internal systems and external clients. You will act as a vital link between our engineering teams and our customers/partners, troubleshooting and resolving integration issues while continually seeking ways to optimize system performance. You will work on next-generation API integrations—such as Tap on Mobile (ToM) and Terminal API—delivering robust solutions for an international client base. If you are passionate about tackling technical challenges in a global environment and want to make a tangible impact in the financial technology industry, this is the role for you.

Day-to-Day Responsibilities

• Onboarding focus: Deliver a structured onboarding package comprising Documentation, Integration Kits, Kickoff Meetings, and Test Equipment.
• Collaborate with integrators and partner developers to embed Worldline’s ECR API into partner ECR environments, enabling secure payments via Terminal API and Tap on Mobile (ToM).
• Produce and maintain developer documentation, sample code, tutorials, and API references; keep integration guides up to date for API product use cases.
• Advise on best practices for API usage, error handling, and monitoring partner developers to accelerate time-to-value and production readiness.
• Troubleshoot and resolve issues related to API connectivity and system interoperability.
• Provide technical support and integration assistance for projects involving API Integrations.
• Collaborate with development and QA teams to ensure robust and reliable integration solutions.
• Communicate effectively in English with clients and internal teams to relay technical information clearly.

Who Are We Looking For

We are seeking a proactive problem-solver with a strong technical background and excellent English communication skills. The ideal candidate is open-minded, flexible, a genuine team player, and capable of working independently in an international context. Experience in system integration, especially within financial services or POS/ECR environments, is a strong asset. A Master’s degree or equivalent is required, with 4–5 years of experience in a similar role, ideally supporting API integrations (including the ECR API). Excellent command of English, both spoken and written, and a good understanding of hardware/software environments are essential. The role requires an open-minded attitude and the ability to work effectively with a distributed, global team; potential locations include Vienna, Warsaw, Paris, Seclin, and Villeurbanne.

At Worldline, you’ll get the chance to be at the heart of the global payments technology industry and shape how the world pays and gets paid. On top of that, you will also:

• Private medical & life insurance
• Public transportation allowance
• Annual bonus

Pursuant to the Article 24 sec. 6 of the Act of 14 June 2024 on the protection of whistleblowers, we inform you that Worldline Financial Services (Europe) S.A., a joint-stock company, Branch in Poland (hereinafter referred to as Worldline) is governed by the Regulations on the receipt of internal reports and taking follow-up actions (hereinafter referred to as the Regulations).

Shape the evolution

We are on an exciting journey towards the next frontiers of payments technology, and we look for big thinkers, people with passion, can-do attitude and a hunger to learn and grow. Here you'll work with ambitious colleagues from around the world, take on unique challenges as a team, and make a real impact on the society. With an empowering culture, strong technology and extensive training opportunities, we help you accelerate your career - wherever you decide to go. Join our global team of 18,000 innovators and shape a tomorrow that is yours to own.

Learn more about life at Worldline at jobs.worldline.com

We are proud to be an Equal Opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex, sexual orientation, gender identity, gender expression, age, status as an individual with a disability, or any applicable legally protected characteristics.