diff --git a/README.md b/README.md
index 2f973e3..1bef699 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,33 @@
 # epics-module-meta
 
-Meta repository with references to third party modules and tags to build them
\ No newline at end of file
+Meta repository with references to third party modules and tags to build them.
+
+This is very barebones, please improve as you see fit.
+This at least allows us to pin down the versions for when we need to rebuild everything
+
+## How to
+
+Create a module yaml file in the `modules` directory, the most common case we build an already tagged version from GFS.
+
+```
+$ cat modules/autosave.yaml
+module: autosave
+repo: git@git.psi.ch:epics_driver_modules/autosave.git
+tag: 5.7.18
+```
+
+Build with:
+```
+./build modules/autosave.yaml
+```
+
+Install with:
+```
+./build modules/autosave.yaml install
+```
+
+If you have your modules directory in a non-standard location:
+```
+export EPICS_MODULES=/path/to/your/modules
+```
+in beforehand.
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..6f0dc90
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,39 @@
+#!/usr/bin/bash
+set -eo pipefail
+WORKDIR=${WORKDIR:-workdir}
+MODULEYAML=$1
+
+if [ ! -f "$MODULEYAML" ]; then
+    echo "Module yaml description $MODULEYAML not found"
+    exit -1
+fi
+
+if [ ! -d "$WORKDIR" ]; then
+    mkdir $WORKDIR
+fi
+
+module=$(yq e '.module' $MODULEYAML)
+repo=$(yq e '.repo' $MODULEYAML)
+tag=$(yq e '.tag' $MODULEYAML)
+
+builddir="$WORKDIR/$module"
+if [ ! -d "${builddir}" ]; then
+    echo je
+    if [ ! "$tag" = "null" ]; then
+        # prioritize tags
+        git clone $repo $builddir -b $tag 
+    else
+        # use commit
+        branch=$(yq e '.branch' $MODULEYAML)
+        commit=$(yq e '.commit' $MODULEYAML)
+        if [ -z "$commit" ]; then
+            echo "Error no tag or commit specified"
+            exit -1
+        fi
+        git clone $repo $builddir -b $branch
+        git -C $builddir checkout $commit
+    fi
+fi
+
+ARCH_FILTER="RHEL8%" make -C $builddir $2
+
diff --git a/modules/motorSim.yaml b/modules/motorSim.yaml
new file mode 100644
index 0000000..334df49
--- /dev/null
+++ b/modules/motorSim.yaml
@@ -0,0 +1,3 @@
+module: motorSim
+repo: git@git.psi.ch:epics_driver_modules/motorMotorSim.git
+tag: 1.2.0
diff --git a/modules/require.yaml b/modules/require.yaml
new file mode 100644
index 0000000..d049208
--- /dev/null
+++ b/modules/require.yaml
@@ -0,0 +1,5 @@
+# For now and example, just to prove that we can build from commits
+module: require
+repo: git@git.psi.ch:epics_driver_modules/require.git
+branch: master
+commit: e2da39ec956c7e6db348f071faa0f6fc4234abf9