diff --git a/conduit-lwt-unix.opam b/conduit-lwt-unix.opam
index 5250b256..c0a4c9c0 100644
--- a/conduit-lwt-unix.opam
+++ b/conduit-lwt-unix.opam
@@ -14,7 +14,7 @@ build: [
 depends: [
   "base-unix"
   "jbuilder" {build & >="1.0+beta9"}
-  "ppx_sexp_conv" {build}
+  "ppx_sexp_conv"
   "conduit-lwt"
   "lwt" {>= "3.0.0"}
   "uri" {>="1.9.4"}
diff --git a/conduit-lwt.opam b/conduit-lwt.opam
index 59c53505..bcf981a5 100644
--- a/conduit-lwt.opam
+++ b/conduit-lwt.opam
@@ -14,7 +14,7 @@ build: [
 depends: [
   "base-unix"
   "jbuilder" {build & >="1.0+beta9"}
-  "ppx_sexp_conv" {build}
+  "ppx_sexp_conv"
   "sexplib"
   "conduit"
   "lwt" {>="3.0.0"}
diff --git a/conduit.opam b/conduit.opam
index 6e18c1a2..3a50fc65 100644
--- a/conduit.opam
+++ b/conduit.opam
@@ -14,7 +14,7 @@ build: [
 ]
 depends: [
   "jbuilder" {build & >="1.0+beta9"}
-  "ppx_sexp_conv" {build}
+  "ppx_sexp_conv"
   "sexplib"
   "astring"
   "uri"
diff --git a/mirage-conduit.opam b/mirage-conduit.opam
index 3e3a03d5..dac29f60 100644
--- a/mirage-conduit.opam
+++ b/mirage-conduit.opam
@@ -15,7 +15,7 @@ build-test: ["jbuilder" "runtest" "-p" name]
 
 depends: [
   "jbuilder" {build & >="1.0+beta9"}
-  "ppx_sexp_conv" {build}
+  "ppx_sexp_conv"
   "sexplib"
   "cstruct"          {>= "3.0.0"}
   "mirage-types-lwt" {>= "3.0.0"}