diff --git a/.gitmodules b/.gitmodules
index 86654af9..c724bb5c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -7,3 +7,7 @@
 [submodule "cryptopp"]
 	path = cryptopp
 	url = https://github.com/weidai11/cryptopp.git
+[submodule "lmdb"]
+	path = lmdb
+	url = https://github.com/LMDB/lmdb.git
+	branch = mdb.RE/0.9
diff --git a/lmdb b/lmdb
new file mode 160000
index 00000000..60d50020
--- /dev/null
+++ b/lmdb
@@ -0,0 +1 @@
+Subproject commit 60d500206a108b2c64ca7e36b0113b2cd3711b98