diff --git a/Documentation/dev-buck.txt b/Documentation/dev-buck.txt
index 0acf04ad86..a41a821a42 100644
--- a/Documentation/dev-buck.txt
+++ b/Documentation/dev-buck.txt
@@ -332,6 +332,31 @@ Using buckd.
 [-] BUILDING...FINISHED 0.2s
 ----
 
+Overwrite Buck's settings
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In the latest version of Buck the wrapper script `buck_common` will source
+one of these files (if they exist): /etc/buck.conf, $HOME/.buck/buck.conf or
+$HOME/.buckrc. The trivial case to overwrite the Buck's default 1GB heap size:
+
+----
+  cat > $HOME/.buckrc <<EOF
+  export BUCK_EXTRA_JAVA_ARGS="\
+  -XX:MaxPermSize=512m \
+  -Xms8000m \
+  -Xmx16000m"
+  EOF
+----
+
+Or to debug BUCK, set BUCK_DEBUG_MODE to anything non-empty, then connect to
+port 8888:
+
+----
+  cat > $HOME/.buckrc <<EOF
+  export BUCK_DEBUG_MODE="yes"
+  EOF
+----
+
 GERRIT
 ------
 Part of link:index.html[Gerrit Code Review]