diff --git a/packages/wcs-api/wcs-api.2017-05-26.01/opam b/packages/wcs-api/wcs-api.2017-05-26.01/opam
index 570db39473f1..a170f2bbafef 100644
--- a/packages/wcs-api/wcs-api.2017-05-26.01/opam
+++ b/packages/wcs-api/wcs-api.2017-05-26.01/opam
@@ -23,6 +23,7 @@ depends: [
   "wcs-lib" {= "2017-05-26.01"}
   "lwt_ssl"
   "cohttp-lwt-unix" {>= "0.20.0" & < "1.0"}
+  "jbuilder"
 ]
 synopsis: "SDK for Watson Conversation Service"
 description: """
diff --git a/packages/wcs-api/wcs-api.2017-05-26.02/opam b/packages/wcs-api/wcs-api.2017-05-26.02/opam
index fe3e7a682070..639c2e183969 100644
--- a/packages/wcs-api/wcs-api.2017-05-26.02/opam
+++ b/packages/wcs-api/wcs-api.2017-05-26.02/opam
@@ -23,6 +23,7 @@ depends: [
   "wcs-lib" {= "2017-05-26.02"}
   "lwt_ssl" | "tls"
   "cohttp-lwt-unix" {< "1.0.0"}
+  "jbuilder" {<="1.0+beta20.2"}
 ]
 synopsis: "SDK for Watson Conversation Service"
 description: """
diff --git a/packages/wcs-api/wcs-api.2017-05-26.03/opam b/packages/wcs-api/wcs-api.2017-05-26.03/opam
index 34c6f455e4cd..7e259f6fd922 100644
--- a/packages/wcs-api/wcs-api.2017-05-26.03/opam
+++ b/packages/wcs-api/wcs-api.2017-05-26.03/opam
@@ -22,6 +22,7 @@ depends: [
   "ocaml" {>= "4.03.0"}
   "wcs-lib" {= "2017-05-26.03"}
   "cohttp-lwt-unix" {>= "1.0.0"}
+  "jbuilder"
 ]
 synopsis: "SDK for Watson Conversation Service"
 description: """
diff --git a/packages/wcs-api/wcs-api.2017-05-26.04/opam b/packages/wcs-api/wcs-api.2017-05-26.04/opam
index e99ec4894413..bdcc8601752e 100644
--- a/packages/wcs-api/wcs-api.2017-05-26.04/opam
+++ b/packages/wcs-api/wcs-api.2017-05-26.04/opam
@@ -22,6 +22,7 @@ depends: [
   "ocaml" {>= "4.03.0"}
   "wcs-lib" {= "2017-05-26.04"}
   "cohttp-lwt-unix" {>= "1.0.0"}
+  "jbuilder"
 ]
 synopsis: "SDK for Watson Conversation Service"
 description: """
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.00/opam b/packages/wcs-lib/wcs-lib.2017-05-26.00/opam
index 7490ad6f50de..ab7153731422 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.00/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.00/opam
@@ -21,7 +21,7 @@ build: [
 depends: [
   "ocaml" {>= "4.03.0"}
   "ocamlfind" {build}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "atdgen" {build & < "1.13.0"}
   "lwt_ssl"
   "cohttp-lwt-unix" {< "1.0.0"}
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.01/opam b/packages/wcs-lib/wcs-lib.2017-05-26.01/opam
index 864c54b9023c..3b3d166ae15a 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.01/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.01/opam
@@ -21,7 +21,7 @@ build: [
 depends: [
   "ocaml" {>= "4.02.3"}
   "ocamlfind" {build}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "atdgen" {build & < "1.13.0"}
 ]
 synopsis: "SDK for Watson Conversation Service"
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.02/opam b/packages/wcs-lib/wcs-lib.2017-05-26.02/opam
index c269cdedf5d0..caae770c3ea6 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.02/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.02/opam
@@ -20,7 +20,7 @@ build: [
 
 depends: [
   "ocaml" {>= "4.02.3"}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "ocaml-migrate-parsetree" {build}
   "atdgen" {build & < "1.13.0"}
   "atd"
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.03/opam b/packages/wcs-lib/wcs-lib.2017-05-26.03/opam
index 42582c214625..0d2cc264b9e4 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.03/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.03/opam
@@ -20,7 +20,7 @@ build: [
 
 depends: [
   "ocaml" {>= "4.02.3"}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "ocaml-migrate-parsetree" {build}
   "atdgen" {build & < "1.13.0"}
   "atd"
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.04/opam b/packages/wcs-lib/wcs-lib.2017-05-26.04/opam
index 6104804e029e..2ea8c2a5d497 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.04/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.04/opam
@@ -20,7 +20,7 @@ build: [
 
 depends: [
   "ocaml" {>= "4.02.3"}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "ocaml-migrate-parsetree" {build}
   "atdgen" {build & < "1.13.0"}
   "atd"
diff --git a/packages/wcs-lib/wcs-lib.2017-05-26.05/opam b/packages/wcs-lib/wcs-lib.2017-05-26.05/opam
index 926ae51cc972..a4a89ab84111 100644
--- a/packages/wcs-lib/wcs-lib.2017-05-26.05/opam
+++ b/packages/wcs-lib/wcs-lib.2017-05-26.05/opam
@@ -20,7 +20,7 @@ build: [
 
 depends: [
   "ocaml" {>= "4.03.0"}
-  "jbuilder"
+  "jbuilder" {<"1.0+beta20.2"}
   "ocaml-migrate-parsetree" {build}
   "atdgen" {build}
   "atd"