diff --git a/packages/mirage-unikernel-dns-secondary-hvt.0.0.2/opam b/packages/mirage-unikernel-dns-secondary-hvt.0.0.2/opam
index 04ac6ea..16f6170 100644
--- a/packages/mirage-unikernel-dns-secondary-hvt.0.0.2/opam
+++ b/packages/mirage-unikernel-dns-secondary-hvt.0.0.2/opam
@@ -38,6 +38,7 @@ depends: [
   "ocaml-solo5" { build & >= "0.8.1" & < "0.9.0" }
   "opam-monorepo" { build & >= "0.3.2" }
   "tcpip" { ?monorepo & >= "7.0.0" & < "9.0.0" }
+  "solo5" { < "0.8.0"}
 ]
 
 x-mirage-opam-lock-location: "mirage/secondary-hvt.opam.locked"
diff --git a/packages/mirage-unikernel-dns-secondary-monitoring-hvt.0.0.2/opam b/packages/mirage-unikernel-dns-secondary-monitoring-hvt.0.0.2/opam
index 63cbb31..3b791e9 100644
--- a/packages/mirage-unikernel-dns-secondary-monitoring-hvt.0.0.2/opam
+++ b/packages/mirage-unikernel-dns-secondary-monitoring-hvt.0.0.2/opam
@@ -41,6 +41,7 @@ depends: [
   "ocaml-solo5" { build & >= "0.8.1" & < "0.9.0" }
   "opam-monorepo" { build & >= "0.3.2" }
   "tcpip" { ?monorepo & >= "7.0.0" & < "9.0.0" }
+  "solo5" { < "0.8.0"}
 ]
 
 x-mirage-opam-lock-location: "mirage/secondary-hvt.opam.locked"