Some words about us

ERSA, located in Alsace near the French-German border, is an entity of CLEARSY specialised in the development of software applications for industry. Our knowledge is mainly applied to the transportation business, especially the Railway sector, but we also provide general computer and software services, especially to our local customers.

We are specialised in the production of ERTMS/ETCS related solutions, in the field of simulation tools for research, demonstration, testing and training, but also in safety related products for on-board or trackside applications. We perform also consulting and training activities.

We deliver our products and services mostly in European countries, but also in Asia. Our customers are Railways Undertakers or Infrastructure Managers, Railways Industries and Research Institutes.


Founded in 1998 as a part of the former ERRI (European Railway Research Institute), ERSA has participated to the development of the first ETCS simulator in Europe within the frame of the UIC A200 project.

In the frame of a contract with UNISIG (at the time also called “Eurosig”), ERSA provided a set of tools used for the creation of the first independent test bench for ETCS on-board systems in Europe, in the premises of CEDEX in Madrid. As a participant of different European projects, ERSA had the opportunity to develop a number of software products used for the demonstration and testing of ETCS. ERSA has provided simulation solutions to the three Laboratories recognised as references in Europe (CEDEX, DLR and MULTITEL).

ERSA follows very closely the development of new European standards and is currently helping the European Railway Agency and the ERTMS Users Group in the consolidation of the specifications of Baseline 3, by the provision of various simulation tools, especially a functional implementation of the ETCS on-board system (EVC) and the ETCS Driver Machine Interface.

In 2001, ERSA was acquired by AEA Technology PLC (UK), trading as the rail division. The business was sold in 2006 to Vision Capital LLC with the subsequent creation of DeltaRail Group Ltd. In 2015 the company was sold to its Executive Directors.

Software engineering

Industrial projects developed by ERSA are based on the use of quality methods in project production and management. ERSA is certified ISO9001:2015.

The development of the ERSA software follows the classical ‘V’ lifecycle and is based on recognised specification methodologies and design tools (SA-RT, SD, Object Oriented Design (UML)). ERSA is using CENELEC standards for safety related software developments.

Software production

ERSA works in Windows and Linux environments, using as far as possible processes, languages and/or libraries which are independent from the operating systems.

All developments are mainly performed on PCs using operating systems such as Linux and Windows 10, Seven.

The most used programming languages are: C++, C and Python. Most applications are using databases, among them MySQL, SQLite, Oracle, Access.

CORBA is used as an abstract communication mechanism in distributed architecture systems.

Graphical user interfaces are developed using the Qt framework.

Project requirements are traced with Microsoft VSTS, especially for safety related projects.

Configuration management is based on SVN. Support is organised with the use of Redmine.

Project planning is based on a tool named Visual Projet. The SCRUM methodology is currently being implemented in order to improve the organisation and execution of projects. It allows stronger motivation and commitment of the staff and a better involvement of the Customer from the beginning and at each delivery step.


We are providing wide range of Consulting Services & World wide happy Clients