diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..531caa4
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module github.com/paulmach/orb
+
+go 1.13
+
+require (
+	github.com/gogo/protobuf v1.3.0
+	github.com/pkg/errors v0.8.1
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..3adcf14
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,7 @@
+github.com/gogo/protobuf v1.3.0 h1:G8O7TerXerS4F6sx9OV7/nRfJdnXgHZu/S/7F2SN+UE=
+github.com/gogo/protobuf v1.3.0/go.mod h1:SlYgWuQ5SjCEi6WLHjHCa1yvBfUnHcTbrrZtXPKa29o=
+github.com/kisielk/errcheck v1.2.0/go.mod h1:/BMXB+zMLi60iA8Vv6Ksmxu/1UDYcXs4uQLJ+jE2L00=
+github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+golang.org/x/tools v0.0.0-20181030221726-6c7e314b6563/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=