**A Type Level Approach to Component Prototyping,
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This presentation addresses an 'old' problem in software engineering: how to build new components from old? The discussion is framed in a particular context: components are represented by their formal specifications, in a state-based style, and prototyped in the functional language Haskell. The problem is tackled from the perspective of classical modular composition in which components are assembled together through a set of algebraic combinators. Haskell libraries implementing a component algebra are showed. We will discuss a possible strongly typed implementation.