Geiser is a generic Emacs/Scheme interaction mode, featuring an enhanced REPL and a set of minor modes that improve Emacs' basic major mode for Scheme. The main features provided are evaluation of forms in the namespace of the current module, macro expansion, loading of files and modules, namespace-aware identifier completion, automatic documentation, jumping to the definition of an identifier, access to documentation, listings of identifiers exported by a given module, and rudimentary support for debugging. Geiser supports Guile and Racket.
DictEm is an extremely customizable DICT client for (X)Emacs. It implements all functions of the client part of the DICT protocol (RFC-2229). Unlike dictionary.el, it widely uses autocompletion that is used for selecting a dictionary and search strategy. It provides several hooks that may be used for buffer postprocessing. Built-in hyperlinking and a highlighting mechanism are based on this ability. It supports the mechanism of virtual dictionaries that can be used for grouping dictionaries from different DICT servers into the client-side virtual dictionary.