All modules are statically bound, which means that they need not (but may) be explicitly declared in the query prolog.
Note: in {{Version|7.2.23}}, many used error codes have been updated for ensure future stability.
{| class="wikitable sortable"
|-
| [[Client Module|Client]]
| Executing commands and queries on remote BaseX servers {{Version|7.2.23}}
| <code>client</code>
| <code><nowiki>http://basex.org/modules/client</nowiki></code>
|-
| [[Process Module|Process]]
| Executing system commands from XQuery {{Version|7.2.23}}
| <code>proc</code>
| <code><nowiki>http://basex.org/modules/proc</nowiki></code>
|-
| [[Validation Module|Validation]]
| Validating documents against DTDs or XML Schema files. {{Version|7.2.23}}
| <code>validate</code>
| <code><nowiki>http://basex.org/modules/validate</nowiki></code>