fortiss software Fasten


An open-source environment for the specification, verification, and assurance of critical systems


FormAl SpecificaTion ENvironment (FASTEN) is an open-source research environment for model-based specification and design of safety critical systems using domain specific languages.

FASTEN makes system and safety engineering models available at different development and safety lifecycle phases, e.g., for the description of the operational design domain (ODD), hazards lists, safety analyses, requirements, system architectures (based on contracts), and safety cases. All these models are deeply integrated with each other via a well-defined traceability mechanism, which allows for automated execution of maintenance activities. Furthermore, FASTEN integrates several verification and validation engines, thus enabling the automated execution of different checks on the specified models.

Already today, systems with safety-critical software and data-based functions, e.g., cars with advanced-driver assistance systems, frequently require software updates for both maintenance and after-market feature enhancements. Since upcoming products such as vehicles with autonomous driving functions will boost this trend to agile development, reapplying traditional manual assurance processes for the entire product on each update is prohibitive. More efficient safety assurance requires a higher degree of automation and reuse of certification artifacts of previous product revisions than possible with today’s development tools.

To overcome this challenge, FASTEN proposes a flexible and extensible open-source framework for prototyping tool-support for agile design and assurance methods for safety-critical embedded systems. The FASTEN tool provides a stack of Domain Specific Languages (DSL) that enables the modeling of different development and assurance artifacts. The underlying modeling viewpoints are deeply integrated via semantically rich traces, which facilitates consistency checks of assurance artifacts.

FASTEN is a research tool prototype in which different functionalities are provided at various Technology Readiness Levels (TRLs) spanning from TRL4 (validated in a lab) to TRL6 (demonstrated in industrially relevant environment).It is intended to demonstrate how different system and system assurance aspects can be modeled by means of DSLs, and how these DSLs help increase the automation degree of system development and safety assurance.



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Further information

 Simon Barner

Your contact

Simon Barner

+49 89 3603522 22


[Translate to English:] Logog Fasten