diff --git a/.gitmodules b/.gitmodules
index 52194b76..a22fbc41 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "tests"]
 	path = tests
 	url = https://github.com/YosysHQ/nextpnr-tests
+[submodule "fpga-interchange-schema"]
+	path = 3rdparty/fpga-interchange-schema
+	url = https://github.com/SymbiFlow/fpga-interchange-schema.git
diff --git a/3rdparty/fpga-interchange-schema b/3rdparty/fpga-interchange-schema
new file mode 160000
index 00000000..6d450bd3
--- /dev/null
+++ b/3rdparty/fpga-interchange-schema
@@ -0,0 +1 @@
+Subproject commit 6d450bd3e14fdbf180f64e4f3585ec3c7427ddb3