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How open data and people-oriented approach revolutionized transportation in Gdańsk

IT services for public transport
Our customer, ZTM Gdańsk, aimed to provide data to developers in an open format, allowing for the creation of various applications tailored to user needs. By utilizing the CKAN platform and developing custom services, we successfully enabled the sharing of real-time information, including timetables and vehicle positions, which greatly improved the experience for public transport passengers.


  • Name:Zarząd Transportu Miejskiego (ZTM) w Gdańsku (Public Transport Authority in Gdansk)
  • Business object:
    Organization and management of public urban passenger transport
  • Founding year: 2005
  • Country: Poland


The client’s goal was to provide the generated data to developers in an open format. The openness of the data allows for the creation of various applications according to the expectations of each demanding user. Thanks to this, public transport passengers organized by ZTM in Gdansk could check the timetable in multiple ways, along with information about any delays of individual ZTM vehicles in Gdansk.


  • Using the CKAN platform to store open static data (which changes relatively infrequently).
  • Building a custom service that allows for sharing data that changes frequently, such as the GPS position of trams and buses.

Which technologies have we applied:

  • Java,
  • Spring-Boot,
  • REST,
  • SOAP,
  • SqlServer,
  • Kubernetes.
ZTM Open Data Gdańsk

Exploring the limitations of traditional traffic management system.

  • Between 2012-2015, the Integrated Traffic Management System TRISTAR was launched in the Tricity (Gdansk, Sopot, Gdynia). Its goal was to improve the quality of transportation, which includes, among other things, collecting information about vehicle traffic in the Tricity. As part of the system, the hardware and software of ZTM in Gdansk were modernized.
  • The technologies used in TRISTAR were built traditionally. This made it difficult to use the system to directly share data about current timetables and GPS positions of buses and trams in a manner that would maintain its operation. ZTM Gdansk needed help preparing an automatic data export from the TRISTAR system and building an architecture allowing for secure sharing. That’s when came to help.

Cooperation begins: and ZTM in Gdańsk.

In 2016, we participated in a tender to create the “Open Data System of ZTM in Gdańsk” and were selected by ZTM in Gdańsk. Our domain knowledge and experience in backend architecture were crucial for the client.

Four specialists from worked on the project: the Chief Solution Architect, the Architect/DevOps Engineer, and two Senior Mobile Developers who provided the necessary expertise and experience in delivering the project. We worked as an independent team in close cooperation with the customer.

The challenges of sharing complex data structures.  

The first step was to decide where to place the open data. Fortunately, the client already had access to the CKAN platform, a data management system for public organizations. For this reason, we chose CKAN as the place to share “Open Data ZTM in Gdańsk”.

To make the information we wanted to share consumable by planners such as Google Maps, Jakdojade, BusLive or Time4BUS we had to prepare it properly. We worked on the data structure related to the timetable, which proved to be quite complicated due to its distribution across various databases and microservices.

We also had to consider the limited resources of the source system. We had to strike a balance between data collection speed and the load on the databases, which are simultaneously used by other ZTM Gdansk applications.

Sharing rapidly changing data (e.g., departure estimates from stops or vehicle positions) required a different approach due to CKAN system limitations. We needed to be able to update the data frequently enough to meet the quality requirements. We shared this data directly from our servers, and CKAN remained the place for its documentation.

Review Quote, with whom we have been cooperating for many years, deserves to be called a reliable and professional business partner on whom one can rely.
Agnieszka Rzeźnikowska
Chief Specialist for Passenger Information System Support Public Transport Authority in Gdańsk
Gdańsk Public Transport

The impact of’s partnership with ZTM in Gdańsk

  • As a result, the team and ZTM in Gdańsk successfully developed applications that collect and share data so planners can easily consume them from other providers, such as Google Maps or Jakdojadę.
  • The entire set of “Open ZTM data in Gdańsk” can be found here:
  • To present the shared data, we created their visualization through an application on the website:  in both desktop and mobile versions.
Mobile application for public transport in Gdańsk

We continue to work on open data for ZTM in Gdańsk, ensuring their timeliness and carefully controlling the downloading of data from the TRISTAR system.


In 2022, we handled 406,639,355 requests for open data in Gdańsk. 

Gdańsk Public Transportation Dynamic Data Open Data

On the other hand, queries for static data (updated once a day) occur hundreds of thousands of times a month. 

Gdańsk Public Transportation Open Data Statistics
Review Quote
The solutions created by the team were executed according to our expectations, and our business goal was achieved.
Agnieszka Rzeźnikowska
Chief Specialist for Passenger Information System Support Public Transport Authority in Gdańsk

In the case of the map, which was made public less than two years ago, we recorded 3,827,046 visits. The promotional campaign and regularly introduced improvements contribute to the increasing interest in the product, as evidenced by the growing number of visits.

Gdańsk Public Transportation Statistics