diff --git a/bin/admin.mli b/bin/admin.mli
deleted file mode 100644
index e69de29b..00000000
diff --git a/bin/client.mli b/bin/client.mli
deleted file mode 100644
index e69de29b..00000000
diff --git a/bin/scheduler.ml b/bin/scheduler.ml
index e317e24f..f1323e52 100644
--- a/bin/scheduler.ml
+++ b/bin/scheduler.ml
@@ -141,14 +141,6 @@ let pools =
     ~docv:"POOLS"
     ["pools"]
 
-let capnp_address =
-  Arg.value @@
-  Arg.opt (Arg.some Capnp_rpc_unix.Network.Location.cmdliner_conv) None @@
-  Arg.info
-    ~doc:"Public address (SCHEME:HOST:PORT) for Cap'n Proto RPC (default: no RPC)"
-    ~docv:"ADDR"
-    ["capnp-address"]
-
 let secrets_dir =
   Arg.required @@
   Arg.(opt (some dir)) (Some "./capnp-secrets") @@
diff --git a/current_ocluster.opam b/current_ocluster.opam
index bf8b6e96..e27bfd3d 100644
--- a/current_ocluster.opam
+++ b/current_ocluster.opam
@@ -8,7 +8,7 @@ authors: ["talex5@gmail.com"]
 homepage: "https://github.com/ocurrent/ocluster"
 bug-reports: "https://github.com/ocurrent/ocluster/issues"
 depends: [
-  "dune" {>= "2.8"}
+  "dune" {>= "3.3"}
   "ppx_deriving"
   "ocluster-api" {= version}
   "lwt" {>= "5.6.1"}
diff --git a/dune-project b/dune-project
index 55f335a8..17d99d8d 100644
--- a/dune-project
+++ b/dune-project
@@ -1,4 +1,4 @@
-(lang dune 2.8)
+(lang dune 3.3)
 (name ocluster)
 (formatting disabled)
 (generate_opam_files true)
diff --git a/obuilder b/obuilder
index ab58e15e..dc987c12 160000
--- a/obuilder
+++ b/obuilder
@@ -1 +1 @@
-Subproject commit ab58e15efae2d9266f493ca3a07ca533153988e7
+Subproject commit dc987c12ccc6cd9729809359e9375bfe5443add9
diff --git a/ocluster-api.opam b/ocluster-api.opam
index 14468f4f..a4236458 100644
--- a/ocluster-api.opam
+++ b/ocluster-api.opam
@@ -7,7 +7,7 @@ authors: ["talex5@gmail.com"]
 homepage: "https://github.com/ocurrent/ocluster"
 bug-reports: "https://github.com/ocurrent/ocluster/issues"
 depends: [
-  "dune" {>= "2.8"}
+  "dune" {>= "3.3"}
   "ppx_deriving"
   "lwt" {>= "5.6.1"}
   "capnp-rpc-lwt" {>= "1.2"}
diff --git a/ocluster.opam b/ocluster.opam
index b4a71b6e..41c73dbe 100644
--- a/ocluster.opam
+++ b/ocluster.opam
@@ -16,7 +16,7 @@ authors: ["talex5@gmail.com"]
 homepage: "https://github.com/ocurrent/ocluster"
 bug-reports: "https://github.com/ocurrent/ocluster/issues"
 depends: [
-  "dune" {>= "2.8"}
+  "dune" {>= "3.3"}
   "ppx_expect" {>= "v0.14.1"}
   "prometheus"
   "ppx_sexp_conv"
diff --git a/scheduler/pool.ml b/scheduler/pool.ml
index 88df85dc..02a94022 100644
--- a/scheduler/pool.ml
+++ b/scheduler/pool.ml
@@ -298,7 +298,7 @@ module Make (Item : S.ITEM)(Time : S.TIME) = struct
     mutable workers : worker Worker_map.t;  (* Connected workers *)
     mutable clients : client_info Client_map.t;
     mutable cluster_capacity : float;
-    mutable pending_cached : (Item.cache_hint, int) Hashtbl.t;
+    pending_cached : (Item.cache_hint, int) Hashtbl.t;
   } and worker = {
     parent : t;
     name : string;
diff --git a/scheduler/pool.mli b/scheduler/pool.mli
index 26ea663a..37a260fb 100644
--- a/scheduler/pool.mli
+++ b/scheduler/pool.mli
@@ -25,7 +25,7 @@ module Inactive_reasons : sig
   val pp : t Fmt.t
 end
 
-module Make (Item : S.ITEM) (Time : S.TIME) : sig
+module Make (Item : S.ITEM) (_ : S.TIME) : sig
   type t
   (** A pool of workers and queued jobs. *)
 
@@ -115,7 +115,7 @@ module Make (Item : S.ITEM) (Time : S.TIME) : sig
 
   val with_worker : t -> string -> (worker -> 'a) -> 'a
   (** [with_worker t name f] is [f worker] if [worker] is in [connected_workers].
-      If not, it temporarily registers it, runs [f], and then releases it. *) 
+      If not, it temporarily registers it, runs [f], and then releases it. *)
 
   val worker_known : t -> string -> bool
   (** [worker_known t name] is [true] when worker [name] has previously registered with this pool,
diff --git a/stress/stress.mli b/stress/stress.mli
deleted file mode 100644
index e69de29b..00000000
diff --git a/test/test.mli b/test/test.mli
deleted file mode 100644
index e69de29b..00000000
diff --git a/test/test_scheduling.ml b/test/test_scheduling.ml
index d40e39b5..75ef60bb 100644
--- a/test/test_scheduling.ml
+++ b/test/test_scheduling.ml
@@ -37,7 +37,7 @@ let job_state x =
   | Sleep -> Error "pending"
 
 let pp_result = Fmt.(result ~ok:string ~error:string)
-let pp_cancel = Fmt.(result ~ok:(const string "cancelled") ~error:(const string "error"))
+let pp_cancel ppf = Fmt.(result ~ok:(const string "cancelled") ~error:(const string "error")) ppf
 
 let println fmt = Fmt.pr (fmt ^^ "@.")
 let print_result = Fmt.pr "%a@." pp_result
diff --git a/test/test_scheduling.mli b/test/test_scheduling.mli
deleted file mode 100644
index e69de29b..00000000