diff --git a/dune-project b/dune-project
index 03d377ad..e4dd40e5 100644
--- a/dune-project
+++ b/dune-project
@@ -1,6 +1,7 @@
 (lang dune 3.9)
 (name eio)
 (formatting disabled)
+(subst disabled)
 (generate_opam_files true)
 (source (github ocaml-multicore/eio))
 (license ISC)
diff --git a/eio.opam b/eio.opam
index 78109b12..7dafd13b 100644
--- a/eio.opam
+++ b/eio.opam
@@ -29,7 +29,6 @@ conflicts: [
   "seq" {< "0.3"}
 ]
 build: [
-  ["dune" "subst"] {dev}
   [
     "dune"
     "build"
diff --git a/eio_linux.opam b/eio_linux.opam
index c4ab6700..3a5d8d40 100644
--- a/eio_linux.opam
+++ b/eio_linux.opam
@@ -20,7 +20,6 @@ depends: [
   "odoc" {with-doc}
 ]
 build: [
-  ["dune" "subst"] {dev}
   [
     "dune"
     "build"
diff --git a/eio_main.opam b/eio_main.opam
index 1d3cad8a..8c8d238f 100644
--- a/eio_main.opam
+++ b/eio_main.opam
@@ -21,7 +21,6 @@ depends: [
   "odoc" {with-doc}
 ]
 build: [
-  ["dune" "subst"] {dev}
   [
     "dune"
     "build"
diff --git a/eio_posix.opam b/eio_posix.opam
index 9d843811..f06e6860 100644
--- a/eio_posix.opam
+++ b/eio_posix.opam
@@ -18,7 +18,6 @@ depends: [
   "odoc" {with-doc}
 ]
 build: [
-  ["dune" "subst"] {dev}
   [
     "dune"
     "build"
diff --git a/eio_windows.opam b/eio_windows.opam
index b24efa54..bb5020c1 100644
--- a/eio_windows.opam
+++ b/eio_windows.opam
@@ -17,7 +17,6 @@ depends: [
   "odoc" {with-doc}
 ]
 build: [
-  ["dune" "subst"] {dev}
   [
     "dune"
     "build"