TTSLI : an Implementation of Tree-Tuple Synchronized Languages Benoit Lecland and Pierre Rety Abstract : Tree-Tuple Synchronized Languages have first been introduced by means of Tree-Tuple Synchronized Grammars (TTSG), and have been reformulated recently by means of (so-called) Constraint Systems (CS), which allowed to prove more properties. A number of applications to rewriting and to concurrency have been presented. TTSLI is an implementation of constraint systems, together with the main operations. It is written in Java, and is available on Lecland's web page.