Redis , by SS, is an in-memory data structure store.


Latest release 6.0.8
Release time 2020-09-10
License BSD (3-clause).
Maintainer The Redis core team.

SS stepped down as the maintainer of Redis in June 2020.

See Also

A Redis-like API for Metakit.


Redis is an in-memory data structure store that persists on disk. The data model is key-value, but many different kinds of values are supported: Strings, Lists, Sets, Sorted Sets, Hashes. It is somewhat like Memcached, but persistent.

Redis is implemented in C with a test suite written in Tcl. The test suite includes a Tcl client library .

The first version of Redis, then called "LMDB" (unrelated to LMDB), was itself implemented in Tcl. SS has published its source code as a Gist on GitHub.


Retcl is an event-driven, object-oriented, Redis client library targeting the Tcl scripting language.

Things that Retcl does which are missing in Salvatore's client are:

  • Pub/Sub support
  • Callbacks specified per subscription pattern / channel
  • Configurable results cache
  • Global and per-command sync / async modes
  • User-defined error handler

Redis and Jim Tcl

You can find a basic Redis client library for Jim Tcl (which was originally another project of antirez) in jimhttp. The library also works in Tcl 8.6 or later.

Redis and Tcl

And there is also another client library in the disque client implementation.

redis-tcl: Tcl library for redis access