Coq au Vin is a blogging engine written in Chicken Scheme. It is designed to appeal to users who have basic Web development skills (i.e., who know HTML and CSS), are able to install their own server-side software, and would rather edit a template than press 105 buttons to customize their sites.
Eleven is a programming language for creating robust, scalable Web applications quickly and easily. It offers a 20x programmer productivity increase over traditional server programming languages like ASP, PHP, and JSP by automating state management and taking control of the application's look and feel. From high-level source code with a simple, C-like syntax, the compiler generates complete, ready-to-run implementations in PHP or mod_perl. Applications maintain their state in a relational database and are inherently fault-tolerant, secure, and scalable.
FramerD is a semi-structured object database integrated with a Scheme-based scripting language which supports multi-lingual programming (with pervasive Unicode), a stable module system for programming in the large, distributed applications (via an extensible RPC protocol), non-deterministic (PROLOG-like) evaluation for search and set operations, multi-threaded program execution, extensive tools for text and language analysis, built-in HTML/XML/MIME parsers, and intuitive (CGI- and FastCGI-based) Web scripting. The built-in object database robustly supports millions of objects and indexed access to those objects, both through disk files and networked servers.
Kahua is a continuation passing style (CPS) application framework and server. It is written using the Gauche implementation of Scheme. It has the advantage that you can use "continuations" easily, so you can solve the typical Web application's problem of process disconnection. It allows you to program declaratively by using S-expressions as a fundamental data type, you can use Kahua's Object Database to persist data, and you can modify the function being run, supporting incremental development.
Scsh is a systems-programming environment for POSIX systems and Win32, embedded in the Scheme programming language. It includes a high-level process notation for writing shell-script like programs, with pipelines and redirections. Scsh additionally provides low-level access to POSIX primitives, plus important non-POSIX extensions such as sockets. Scsh is implemented on top of Scheme48, a portable bytecode implementation of Scheme. A number of user-contributed extensions are available, including an extensible HTTP and FTP server, a socket-level PostgreSQL interface, a programmable text formatting language, and a Postscript generation language.