DCAS handbook

Running

Now that you have dcas binary let’s see how to use it and what it can do.

If you want to start the server right here, right now, launch binary without arguments:

$ ./dcas

Getting help

Take a look at help page (dcas help):

$ ./dcas help
Note: all commands except `start` operate in current work dir. For `start` command see `launcher start --help`

Usage: launcher [OPTIONS] [COMMAND]

Commands:
  start          (default) run all modules specified by files in `{data_dir}/config/` dir
  resolve-token  Proc: fetches token of given user name, writes it to stdout
  migrate        Proc: Back up main DB, create new one and copy data to it
  build-info     Proc: build info
  main           Service: main (database, DC http + gw, presences, longpoll, etc)
  cdn            Service: CDN
  botfather      Bot: "Botfather"
  bridge-tg      Bot: Telegram Bridge
  help           Print this message or the help of the given subcommand(s)

Options:
      --restart-on-fail  Restart command in the same process if it has returned an error
  -h, --help             Print help

Here you can see the list of commands your build supports. There are three kinds of commands and one special command:

  • procedures (migrate, build-info, help, etc): short-time maintenance/administration work;
  • services (main, cdn, voice, etc): internal;
  • bots (bridge-tg, botfather, etc): bots;
  • start: convenience command that launches all services and bots described by configuration files;

Checking build info

Check build info by running dcas build-info. You should see something like this:

$ ./dcas build-info
launcher build 286 2026-08-07 debug
   compiled at 2026-08-11
   commit b78c09 (derived from v0.2.0)

Features: botfather, bridge-tg, build-info, cdn, embeds, main

First paragraph of build-info tells us build date and revision. This piece of info is helpful if you happen to find and report an error.

Second paragraph lists “features”: parts of server that can be enabled or disabled at build time. For this quick tour make sure your build of dcas has at least main, cdn and client-bundled features available.