Mustache is a web template system with implementations available for ActionScript, C++, Clojure, CoffeeScript, ColdFusion, Common Lisp, D, Dart, Delphi, Erlang, Fantom, Go, Haskell, Io, Java, JavaScript, Julia, Lua, .NET, Objective-C, OCaml, Perl, PHP, Pharo, Python, R, Racket, Ruby, Rust, Scala, Smalltalk, Swift, Tcl, CFEngine and XQuery.

Mustache is described as a "logic-less" system because it lacks any explicit control flow statements like if and else conditionals or for loops; however, both looping and conditional evaluation can be achieved using section tags processing lists and lambdas.