use some sneaky codegen to get the 'version' variable

.gitignore

@@ -1 +1,3 @@
-_build/
+_build/
+_opam/
+*.install

dune-project

@@ -1,13 +1,21 @@
 (lang dune 3.8)
 (name talircd)
+(version 0.0.1)
+
 (generate_opam_files true)
+
 (package
  (name talircd)
- (depends
-   ocaml
-   dune
-   (lwt (= 5.7.0))
-   (ppx_expect (= v0.16.0))
-   (ppx_deriving (= 5.2.1))
-   (fmt (= 0.9.0))
-   (ptime (= 1.1.0))))
+ (synopsis "IRC server")
+ (description "IRC server for cats written in ocaml")
+ (license "LGPL-2.0-or-later")
+ (homepage "https://git.lain.faith/iitalics/talircd/")
+ (bug_reports "https://git.lain.faith/iitalics/talircd/issues")
+ (authors "iitalics <git.lain.faith/iitalics>")
+ (maintainers "iitalics <git.lain.faith/iitalics>")
+ (depends ocaml dune
+  (lwt (= 5.7.0))
+  (ppx_expect (= v0.16.0))
+  (ppx_deriving (= 5.2.1))
+  (fmt (= 0.9.0))
+  (ptime (= 1.1.0))))

lib/server/dune

@@ -6,3 +6,10 @@
    logging irc data)
  (inline_tests)
  (preprocess (pps ppx_expect)))
+
+(rule
+ (package talircd)
+ (target "meta_server_info.ml")
+ (action
+  (with-stdout-to %{target}
+   (echo "let version = \"%{version:talircd}\";;"))))

lib/server/server_info.ml

@@ -1,4 +1,7 @@
 open! Import
+include (Meta_server_info : sig
+           val version : string
+         end)
 
 let tz_offset_s = Ptime_clock.current_tz_offset_s ()
 let pp_time = Ptime.pp_human () ?tz_offset_s
@@ -37,15 +40,11 @@ let default_conf = {
   init_cmode = Mode.Set.of_list [`n; `s; `t];
 }
 
-let admin_info = "the admin of this server is @iitalics@octodon.social"
-let version = "0.0.0"
-(* TODO: generate version string at build time? *)
-
 let make ?(conf = default_conf) ~hostname ~motd () = {
-  version = version;
+  version;
   created = Fmt.str "%a" pp_time (Ptime_clock.now ());
+  admin_info = "the admin of this server is @iitalics@octodon.social";
   hostname;
-  admin_info;
   motd;
   conf;
 }

motd.txt

@@ -0,0 +1,6 @@
+--------------------------------------------
+MEOW MEOW MEOW MEOW MEOW MEOW MEOW MEOW MEOW
+Meow Meow Meow Meow Meow Meow Meow Meow Meow
+meow meow meow meow meow meow meow meow meow
+meow meow meow meow meow meow meow meow meow
+--------------------------------------------

talircd.opam

@@ -1,5 +1,13 @@
 # This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
+version: "0.0.1"
+synopsis: "IRC server"
+description: "IRC server for cats written in ocaml"
+maintainer: ["iitalics <git.lain.faith/iitalics>"]
+authors: ["iitalics <git.lain.faith/iitalics>"]
+license: "LGPL-2.0-or-later"
+homepage: "https://git.lain.faith/iitalics/talircd/"
+bug-reports: "https://git.lain.faith/iitalics/talircd/issues"
 depends: [
   "ocaml"
   "dune" {>= "3.8"}