diff --git a/service/conf.ml b/service/conf.ml
index 01bf7d1b..c0e3a4b9 100644
--- a/service/conf.ml
+++ b/service/conf.ml
@@ -116,6 +116,18 @@ let pool_of_arch = function
   | `Ppc64le -> "linux-ppc64"
   | `Riscv64 -> "linux-riscv64"
 
+let disabled_arches = [ `Riscv64 (* Unsufficient capacity in the pool *) ]
+
+(* Arches supported by [distro] but unsupported by [DD.master_distro]. *)
+let supplementary_arches ov master_distro distro =
+  if List.mem distro (List.map DD.resolve_alias DD.latest_distros) then
+    let master_distro_arches = DD.distro_arches ov (master_distro :> DD.t)
+    and distro_arches = DD.distro_arches ov (distro :> DD.t) in
+    List.filter
+      (fun arch -> not (List.mem arch master_distro_arches))
+      distro_arches
+  else []
+
 let platforms ~include_macos opam_version =
   let v ?(arch = `X86_64) label distro ocaml_version =
     {
@@ -134,12 +146,17 @@ let platforms ~include_macos opam_version =
     let label = DD.latest_tag_of_distro (distro :> DD.t) in
     let tag = DD.tag_of_distro (distro :> DD.t) in
     let ov = OV.(Releases.latest |> with_just_major_and_minor) in
+    let filter_disabled =
+      List.filter_map (fun arch ->
+          if List.mem arch disabled_arches then None
+          else Some (v ~arch label tag ov))
+    in
     if distro = master_distro then
       v label tag (OV.with_variant ov (Some "flambda"))
-      :: List.map
-           (fun arch -> v ~arch label tag ov)
-           (DD.distro_arches ov (distro :> DD.t))
-    else [ v label tag ov ]
+      :: filter_disabled (DD.distro_arches ov (distro :> DD.t))
+    else
+      v label tag ov
+      :: filter_disabled (supplementary_arches ov master_distro distro)
   in
   let make_release ?arch ov =
     let distro = DD.tag_of_distro (master_distro :> DD.t) in