diff --git a/scripts/update_hashes.sh b/scripts/update_hashes.sh
new file mode 100755
index 000000000..133bf848a
--- /dev/null
+++ b/scripts/update_hashes.sh
@@ -0,0 +1,49 @@
+#! /bin/sh
+
+script_dir="$(cd "$(dirname "$0")" && echo "$(pwd -P)/")"
+cd "$script_dir"/..
+
+branch=$1
+has_git() {
+    which git && [ -d .git ]
+}
+
+if has_git && ! [ -z "$(git status -s)" ] ; then
+    echo "This script cannot be applied within a dirty git directory,"
+    echo "you need 'stash' or 'commit' your changes before."
+    exit 1
+fi
+
+set -e
+
+current_hash_genesis=`jq '.hash' < src/proto_genesis/lib_protocol/src/TEZOS_PROTOCOL`
+echo "Genesis's current hash: $current_hash_genesis"
+genesis_tmpdir=`mktemp -d`
+mkdir $genesis_tmpdir/src
+cp src/proto_genesis/lib_protocol/src/*.ml src/proto_genesis/lib_protocol/src/*.mli $genesis_tmpdir/src/
+grep -v '"hash"' < src/proto_genesis/lib_protocol/src/TEZOS_PROTOCOL > $genesis_tmpdir/src/TEZOS_PROTOCOL
+new_hash_genesis=`./tezos-protocol-compiler $genesis_tmpdir/tmp $genesis_tmpdir/src | cut -d' ' -f2`
+echo "Genesis's new hash: $new_hash_genesis"
+if [ "$current_hash_genesis" != "$new_hash_genesis" ]
+then
+    find . -type f -exec sed "s/$current_hash_genesis/$new_hash_genesis/g" -i {} \;
+    git commit -a -m "Update proto Genesis's hash"
+else
+    "Proto Genesis's hash hasn't changed, nothing to do"
+fi
+
+current_hash_alpha=`jq '.hash' < src/proto_alpha/lib_protocol/src/TEZOS_PROTOCOL`
+echo "Alpha's current hash: $current_hash_alpha"
+alpha_tmpdir=`mktemp -d`
+mkdir $alpha_tmpdir/src
+cp src/proto_alpha/lib_protocol/src/*.ml src/proto_alpha/lib_protocol/src/*.mli $alpha_tmpdir/src/
+grep -v '"hash"' < src/proto_alpha/lib_protocol/src/TEZOS_PROTOCOL > $alpha_tmpdir/src/TEZOS_PROTOCOL
+new_hash_alpha=`./tezos-protocol-compiler $alpha_tmpdir/tmp $alpha_tmpdir/src | cut -d' ' -f2`
+echo "Alpha's new hash: $new_hash_alpha"
+if [ "$current_hash_alpha" != "$new_hash_alpha" ]
+then
+    find . -type f -exec sed "s/$current_hash_alpha/$new_hash_alpha/g" -i {} \;
+    git commit -a -m "Update proto Alpha's hash"
+else
+    "Proto Alpha's hash hasn't changed, nothing to do"
+fi