SK Signet

Revamping an EV Charger Interface

SK Signet, a leading provider of Electric Vehicle (EV) charging solutions, recognized the need to upgrade the user interface for their EV chargers. The existing solution, based on an older version of Qt, had accumulated technical debt and lacked modern features. The intertwined business logic and complex JavaScript code in QML files made the software difficult to maintain and extend. SK Signet sought a solution that would overcome these limitations and deliver a performant, scalable application for their next-generation chargers.

Step-by-step migration to Slint

KDAB - in collaboration with their partner tQCS - took on the challenge of overhauling the UI. The customer decided to port the application from Qt to Slint, a new technology that offered flexibility, high performance, and competitive licensing. The migration process was carried out step by step, ensuring a fully functional application throughout the transition. KDAB leveraged Slint's support for multiple backends, including a Qt backend, to keep the non-UI parts of Qt intact and working with the Slint-based UI.

During the migration, KDAB had to find replacements for various functionalities provided by Qt but outside the scope of Slint. This experience led KDAB to initiate an internal R&D project to develop a package of free tools thus establishing a set of C++ libraries for developing C++ applications when Qt libraries are not available. [LINK and Name of tool(s)]

A smooth transition

The transition to Slint was straightforward. The project was CMake-based, so the team only needed to update the compiler and install the Rust toolchain. The Slint language was easy to learn, as it shares certain concepts with Qt QML, and the developer experience was further enhanced in this case by Slint's Visual Studio Code plugin, which provided Live-Preview and autocompletion, among other features.

Throughout the project, the Slint team provided exceptional support. Despite Slint being a new technology with some missing features compared to Qt, all the shortcomings encountered during the project were either already fixed or planned in the development roadmap.