use a local git+file pin, as suggested by @reynir

.cirrus.yml

@@ -7,7 +7,6 @@ freebsd_client_task:
   mirage_script: eval `opam env` && opam install --confirm-level=unsafe-yes "mirage>=4.8.0"
   configure_script: eval `opam env` && cd mirage-client && mirage configure -t hvt
   depend_script: eval `opam env` && cd mirage-client && gmake depend
-  copy_script: rm -rf mirage-client/duniverse/miragevpn/* && cp -R dune-project miragevpn.opam src mirage mirage-client/duniverse/miragevpn/
   build_script: eval `opam env` && cd mirage-client && gmake build
   client_artifacts:
     path: mirage-client/dist/ovpn-client.hvt
@@ -18,7 +17,6 @@ freebsd_router_task:
   mirage_script: eval `opam env` && opam install --confirm-level=unsafe-yes "mirage>=4.8.0"
   configure_script: eval `opam env` && cd mirage-router && mirage configure -t hvt --enable-monitoring
   depend_script: eval `opam env` && cd mirage-router && gmake depend
-  copy_script: rm -rf mirage-router/duniverse/miragevpn/* && cp -R dune-project miragevpn.opam src mirage mirage-router/duniverse/miragevpn/
   build_script: eval `opam env` && cd mirage-router && gmake build
   router_artifacts:
     path: mirage-router/dist/ovpn-router.hvt
@@ -29,7 +27,6 @@ freebsd_server_task:
   mirage_script: eval `opam env` && opam install --confirm-level=unsafe-yes "mirage>=4.8.0"
   configure_script: eval `opam env` && cd mirage-server && mirage configure -t hvt
   depend_script: eval `opam env` && cd mirage-server && gmake depend
-  copy_script: rm -rf mirage-server/duniverse/miragevpn/* && cp -R dune-project miragevpn.opam src mirage mirage-server/duniverse/miragevpn/
   build_script: eval `opam env` && cd mirage-server && gmake build
   server_artifacts:
     path: mirage-server/dist/ovpn-server.hvt

mirage-client/config.ml

@@ -7,7 +7,7 @@ let data = generic_kv_ro ~key:data_key "configuration"
 
 let miragevpn_handler =
   let packages =
-    let pin = "git+https://github.com/robur-coop/miragevpn.git" in
+    let pin = "git+file://" ^ Filename.dirname (Sys.getcwd ()) in
     [
       package "logs";
       package ~pin ~sublibs:[ "mirage" ] "miragevpn";

mirage-router/config.ml

@@ -9,7 +9,7 @@ let private_ipv4 = create_ipv4 ~group:"private" private_ethernet private_arp
 
 let miragevpn_handler =
   let packages =
-    let pin = "git+https://github.com/robur-coop/miragevpn.git" in
+    let pin = "git+file://" ^ Filename.dirname (Sys.getcwd ()) in
     [
       package "logs";
       package ~pin ~sublibs:[ "mirage" ] "miragevpn";

mirage-server/config.ml

@@ -4,7 +4,7 @@ open Mirage
 
 let miragevpn_handler =
   let packages =
-    let pin = "git+https://github.com/robur-coop/miragevpn.git" in
+    let pin = "git+file://" ^ Filename.dirname (Sys.getcwd ()) in
     [
       package "logs";
       package ~pin ~sublibs:[ "mirage" ] "miragevpn";