Software quality back on track | ProRail

We helped ProRail decrease the amount of errors in releases and increase the pace of delivery with the same capacity

ProRail is responsible for the maintenance and operation of the rail network in the Netherlands. They boast an incredibly busy rail network: 7,000 kilometres of track, 2,500 crossings, 7,000 railroad switches, and 400 railways stations.

The challenge

Being responsible for the maintenance and operation of the rail network means that ProRail needs to control every single aspect of the infrastructure. In order to achieve this, ProRail makes use of technical drawings that describe each aspect of the infrastructure.

Part of this infrastructure is railway signalling. Railway engineers use specialised software to create and validate all technical drawings in this area. For example, the software helps checking whether the drawings meet the comprehensive and rigorous drawing and design rules. This software is where SIG was specifically involved in.

ProRail makes use of the services of RIGD-LOXIA, a company that develops the software to make and modify the drawings for railway signalling. However, the responsibilities of this software and the resulting drawings were far-reaching: security, safety, operational costs—there was a lot at stake.

There was also a need to change the foundation of the software, but that was only possible after achieving a substantial higher quality level. ProRail and RIGD-LOXIA needed to ensure the software was of the highest quality to achieve their goals, and SIG was asked to help with the quality assessment and improvement.

The solution

ProRail, RIGD-LOXIA and SIG jointly de ned goals and metrics to track progress. Examples of such goals are reduction of legacy code, improved code quality and way of working, and adherence to a new software architecture.


“First our developers were skeptical about SIG. They were afraid of meddling and undermining their autonomy, but after several sessions they felt helped and became more interested. They experienced their software became better. The adversarial sessions were very important in this. Now they are actively pursuing software quality.”

Nico van Didden, Project Manager, ProRail


The original software was poorly maintainable, which was a risk giving the safety implications. In recent years ProRail worked hard to deliver “first-time-right” software, and with success: “New features are delivered at once, first-time- right, whereas in the past several fixes were necessary for a flawless release.” This means a huge efficiency improvement. Maintainability is instrumental here, because checks need to be quickly and accurately added and adjusted to the software.

SIG’s assessment did not just measure the quality of the software, but the score itself also served as a motivating catalyst among staff. In addition, it sets a standard for new potential employees: “It is also striking that candidates sometimes withdrew when they became aware of our high- quality standards during a job interview.”

As a result of the cooperation between ProRail, RIGD-LOXIA and SIG, the management of ProRail/RIGD-LOXIA is now convinced that:

  • Code quality can be controlled.
  • High quality really impacts costs and time-to-market.
  • Quality awareness leads to employees who are proud of their work.
  • High quality standards attract better qualified employees.

Results:

  • Significantly less errors in releases and increased pace of delivery with same capacity.
  • Fostered higher level of quality awareness of developers.
  • Higher job satisfaction and increased motivation of developers.
  • Improved development process.
  • Increased code quality.