diff --git a/xdg/basedir/README b/xdg/basedir/README
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+The basedir module implements the XDG Base Directory Specification as described
+in (https://specifications.freedesktop.org/basedir-spec/latest/).
diff --git a/xdg/basedir/basedir.ha b/xdg/basedir/basedir.ha
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+// Returns the single base directory relative to which user-specific data files
+// should be written, which is defined by $XDG_DATA_HOME. If $XDG_DATA_HOME is
+// either not set or empty, a default equal to $HOME/.local/share is used.
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn data_home (prog: str = "") str = {
+	// TODO
+};
+
+// Returns the single base directory relative to which user-specific
+// configuration files should be written, which is defined by $XDG_CONFIG_HOME.
+// If $XDG_CONFIG_HOME is either not set or empty, a default equal to
+// $HOME/.config is used.
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.s
+export fn config_home (prog: str = "") str = {
+	// TODO
+};
+
+// Returns the single base directory relative to which user-specific state data
+// that should persist between (application) restarts, but that is not important
+// or portable enough to the user that it should be stored. It is defined by
+// $XDG_STATE_HOME. It may contain:
+// 
+// - actions history (logs, history, recently used files, …)
+// - current state of the application that can be reused on a restart (view,
+//   layout, open files, undo history, …)
+//
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn state_home (prog: str = "") str = {
+	// TODO
+};
+
+// CacheHome returns the single base directory relative to which user-specific
+// non-essential (cached) data should be written, which is defined by
+// $XDG_CACHE_HOME. If $XDG_CACHE_HOME is either not set or empty, a default
+// equal to $HOME/.cache is used.
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn cache_home (prog: str = "") str = {
+	// TODO
+};
+
+// Returns the single base directory relative to which user-specific runtime
+// files and other file objects should be placed, which is defined by
+// $XDG_RUNTIME_DIR. This module does not provide a fallback directory. If this
+// function returns an error, applications should fall back to a replacement
+// directory with similar capabilities (in accordance with §3) and print a
+// warning message.
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn runtime_dir (prog: str = "") str = {
+	// TODO
+};
+
+// Returns the set of preference ordered base directories relative to which data
+// files should be searched, which is defined by $XDG_DATA_DIRS. If
+// $XDG_DATA_DIRS is either not set or empty, a value equal to
+// /usr/local/share/:/usr/share/ is used. It is reccomended to call [[data_all]]
+// instead for most use cases.
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn data_dirs (prog: str = "") []str = {
+	// TODO
+};
+
+// Returns set of preference ordered base directories relative to which
+// configuration files should be searched, which is defined by $XDG_CONFIG_DIRS.
+// If $XDG_CONFIG_DIRS is either not set or empty, a value equal to /etc/xdg is
+// used. It is reccomended to call [[config_all]] instead for most use cases.
+//
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn config_dirs (prog: str = "") []str = {
+	// TODO
+};
+
+// Returns the result of [[data_home]] in front of [[data_dirs]].
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn data_all (prog: str = "") []str = {
+	// TODO
+};
+
+// Returns the result of [[config_home]] in front of [[config_dirs]].
+// 
+// The memory is statically allocated and must not be free'd. It may be
+// overwritten later, so use [[strings::dup]] to extend its lifetime.
+export fn config_all (prog: str = "") []str = {
+	// TODO
+};