This paper presents an environment to support the use of specification for mixed systems, i.e. systems with both dynamic (behaviour, communication, concurrency) and static (data type) aspects. We provide an open and extensible environment based on the KORRIGAN specification model. This model uses a hierarchy of view concepts to specify data types, behaviours and compositions in a uniform way. The key notion behind a view is the symbolic transition system. A good environment supporting such a model needs to interface with existing languages and tools. At the core of our environment is the CLIS library which is devoted to the representation of our view concepts and existing specification languages. Our environment is implemented using the object-oriented language PYTHON. It provides an integration process for new tools, a specification library, a parser library, LOTOS generation and object-oriented code generation for KORRIGAN specifications.