cafeobj 1.6.0-2 (armhf binary) in ubuntu focal

 CafeOBJ is a most advanced formal specification language which
 inherits many advanced features (e.g. flexible mix-fix syntax,
 powerful and clear typing system with ordered sorts, parameteric
 modules and views for instantiating the parameters, and module
 expressions, etc.) from OBJ (or more exactly OBJ3) algebraic
 specification language.
 .
 CafeOBJ is a language for writing formal (i.e. mathematical)
 specifications of models for wide varieties of software and systems,
 and verifying properties of them. CafeOBJ implements equational logic
 by rewriting and can be used as a powerful interactive theorem proving
 system. Specifiers can write proof scores also in CafeOBJ and doing
 proofs by executing the proof scores.
 .
 CafeOBJ has state-of-art rigorous logical semantics based on
 institutions. The CafeOBJ cube shows the structure of the various
 logics underlying the combination of the various paradigms implemented
 by the language. Proof scores in CafeOBJ are also based on institution
 based rigorous semantics, and can be constructed using a complete set
 of proof rules.