diff --git a/dns-certify.opam b/dns-certify.opam
index 149f58870..9a38c04c9 100644
--- a/dns-certify.opam
+++ b/dns-certify.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "dns-tsig" {= version}
diff --git a/dns-cli.opam b/dns-cli.opam
index 66c93a2ce..4ae702c8d 100644
--- a/dns-cli.opam
+++ b/dns-cli.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "dns-tsig" {= version}
diff --git a/dns-client.opam b/dns-client.opam
index 89f0412f3..55442d271 100644
--- a/dns-client.opam
+++ b/dns-client.opam
@@ -12,7 +12,7 @@ build: [
 ]
 
 depends: [
-  "dune" {>="1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "cstruct" {>= "4.0.0"}
   "fmt" {>= "0.8.8"}
diff --git a/dns-mirage.opam b/dns-mirage.opam
index dc302b510..e2136e69d 100644
--- a/dns-mirage.opam
+++ b/dns-mirage.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "ipaddr" {>= "4.0.0"}
diff --git a/dns-resolver.opam b/dns-resolver.opam
index 93e5b1f08..e16fc4a34 100644
--- a/dns-resolver.opam
+++ b/dns-resolver.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "dns-server" {= version}
diff --git a/dns-server.opam b/dns-server.opam
index 937366c77..8e11ae363 100644
--- a/dns-server.opam
+++ b/dns-server.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "dns-mirage" {= version}
diff --git a/dns-tsig.opam b/dns-tsig.opam
index e398a0f68..0a4014eb0 100644
--- a/dns-tsig.opam
+++ b/dns-tsig.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "dns" {= version}
   "nocrypto" {>= "0.5.4"}
diff --git a/dns.opam b/dns.opam
index efa6ae090..9362812e9 100644
--- a/dns.opam
+++ b/dns.opam
@@ -8,7 +8,7 @@ bug-reports: "https://github.com/mirage/ocaml-dns/issues"
 license: "BSD2"
 
 depends: [
-  "dune" {>= "1.2.0"}
+  "dune" {>= "1.4.0"}
   "ocaml" {>= "4.07.0"}
   "rresult" "astring" "fmt" "logs" "ptime"
   "domain-name" {>= "0.3.0"}
diff --git a/dune-project b/dune-project
index 4da0e2863..3fa9e14c3 100644
--- a/dune-project
+++ b/dune-project
@@ -1,3 +1,3 @@
-(lang dune 1.2)
+(lang dune 1.4)
 (name dns)
 (using menhir 2.0)