diff --git a/documentation/userguide/configmodel.rst b/documentation/userguide/configmodel.rst
index 019a888092b3554755b4e969c5fe109c057ec6a0..b50e4b14b65e9e154dad90f0a793cf8e4d528498 100644
--- a/documentation/userguide/configmodel.rst
+++ b/documentation/userguide/configmodel.rst
@@ -129,7 +129,7 @@ macro                   scope
 ``${param:builddir}``   build.<component>.{params, prebuild, build, postbuild, clean, artifacts}               Directory in which the component should be built, if the component's build system supports separation of source and build trees.
 ``${param:configdir}``  build.<component>.{params, prebuild, build, postbuild, clean, artifacts}               Directory containing the config store. This MUST only be used for resolving files that already exist in the store.
 ``${param:jobs}``       build.<component>.{params, prebuild, build, postbuild, clean, artifacts}               Maximum number of low level parallel jobs specified on the command line. To be passed to (e.g.) make as ``-j${param:jobs}``.
-``${btvar:<name>}``	build.<component>.{params, prebuild, build, postbuild, clean, artifacts}               Build-time variables. The variable names, along with default values are declared in buildex.btvars, and the user may override the value on the command line.
+``${btvar:<name>}``	build.<component>.{params, prebuild, build, postbuild, clean, artifacts}, run.rtvars   Build-time variables. The variable names, along with default values are declared in buildex.btvars, and the user may override the value on the command line.
 ``${param:join_equal}`` build.<component>.{prebuild, build, postbuild, clean}                                  String  containing all of the component's parameters (from its params dictionary), concatenated as ``key=value`` pairs.
 ``${param:join_space}`` build.<component>.{prebuild, build, postbuild, clean}                                  String  containing all of the component's parameters (from its params dictionary), concatenated as ``key value`` pairs.
 ``${artifact:<name>}``  build.<component>.{params, prebuild, build, postbuild, clean, artifacts}, build.btvars Build path of an artifact declared by another component. Usage of these macros determine the component build dependency graph.
diff --git a/shrinkwrap/utils/config.py b/shrinkwrap/utils/config.py
index 0de5ff3eb758e3e26636e5a70f47bf771dded82b..d55086cc79dc254be391e5372ec3404cc355872f 100644
--- a/shrinkwrap/utils/config.py
+++ b/shrinkwrap/utils/config.py
@@ -653,6 +653,8 @@ def resolver(config, rtvars={}, clivars={}):
 		},
 		'artifact': {k: v['dst']
 				for k, v in config['artifacts'].items()},
+		'btvar': {k: v['value']
+				for k, v in config['buildex']['btvars'].items()},
 	}
 	for k in run['rtvars']:
 		v = run['rtvars'][k]