diff --git a/CHANGES.md b/CHANGES.md
index bcc7ad96..dacded90 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,11 @@
+# unreleased
+------------
+
+ - [deps] Bump toolchain so minimal `ppxlib` is 0.26, in order to fix
+   some `ppx_import` oddities. This means our lower bound for the Jane
+   Street packages is now `v0.15`, which should be fine for the
+   foreseeable future (@ejgallego, #813)
+
 # coq-lsp 0.2.0: From Green to Blue
 -----------------------------------
 
diff --git a/coq-lsp.opam b/coq-lsp.opam
index cf4ddd26..950f6166 100644
--- a/coq-lsp.opam
+++ b/coq-lsp.opam
@@ -34,23 +34,23 @@ depends: [
   "menhir"       { >= "20220210" }
 
   # unit testing
-  "ppx_inline_test"     { >= "0.14.1" }
+  "ppx_inline_test"     { >= "v0.15.0" }
 
   # Uncomment this for releases
   # "coq"          { >= "8.17" < "8.18"  }
 
   # coq deps: remove this for releases
-  "ocamlfind" {>= "1.8.1"}
-  "zarith" {>= "1.11"}
+  "ocamlfind" {>= "1.9.1"}
+  "zarith" {>= "1.13"}
 
   # serlib deps: see what we need to keep for release
-  "ppx_deriving"        { >= "4.2.1"    }
-  "ppx_deriving_yojson" { >= "3.4"      }
-  "ppx_import"          { >= "1.5-3"    }
-  "sexplib"             { >= "v0.13.0" & < "v0.18" }
-  "ppx_sexp_conv"       { >= "v0.13.0" & < "v0.18" }
-  "ppx_compare"         { >= "v0.13.0" & < "v0.18" }
-  "ppx_hash"            { >= "v0.13.0" & < "v0.18" }
+  "ppx_deriving"        { >= "5.2"                 }
+  "ppx_deriving_yojson" { >= "3.7.0"               }
+  "ppx_import"          { >= "1.11.0"              }
+  "sexplib"             { >= "v0.15.0" & < "v0.18" }
+  "ppx_sexp_conv"       { >= "v0.15.0" & < "v0.18" }
+  "ppx_compare"         { >= "v0.15.0" & < "v0.18" }
+  "ppx_hash"            { >= "v0.15.0" & < "v0.18" }
 ]
 
 depopts: ["lwt" "logs"]
diff --git a/lsp/jLang.ml b/lsp/jLang.ml
index 7df98eb9..e5490703 100644
--- a/lsp/jLang.ml
+++ b/lsp/jLang.ml
@@ -88,3 +88,26 @@ module Diagnostic = struct
     let message = Pp.to_string message in
     _t_to_yojson { range; severity; message; data }
 end
+
+module Stdlib = JStdlib
+
+module With_range = struct
+  type 'a t = [%import: ('a Lang.With_range.t[@with Lang.Range.t := Range.t])]
+  [@@deriving yojson]
+end
+
+module Ast = struct
+  module Name = struct
+    type t = [%import: Lang.Ast.Name.t] [@@deriving yojson]
+  end
+
+  module Info = struct
+    type t =
+      [%import:
+        (Lang.Ast.Info.t
+        [@with
+          Lang.Range.t := Range.t;
+          Lang.With_range.t := With_range.t])]
+    [@@deriving yojson]
+  end
+end
diff --git a/lsp/jLang.mli b/lsp/jLang.mli
index 3aba7f17..2b59f7b8 100644
--- a/lsp/jLang.mli
+++ b/lsp/jLang.mli
@@ -38,3 +38,9 @@ module Diagnostic : sig
     [@@deriving yojson]
   end
 end
+
+module Ast : sig
+  module Info : sig
+    type t = Lang.Ast.Info.t [@@deriving yojson]
+  end
+end
diff --git a/lsp/jStdlib.ml b/lsp/jStdlib.ml
new file mode 100644
index 00000000..5995cbaf
--- /dev/null
+++ b/lsp/jStdlib.ml
@@ -0,0 +1,5 @@
+module Result = struct
+  include Stdlib.Result
+
+  type ('a, 'e) t = [%import: ('a, 'e) Stdlib.Result.t] [@@deriving yojson]
+end
diff --git a/petanque/json/jAgent.ml b/petanque/json/jAgent.ml
index dac37aa8..58c39789 100644
--- a/petanque/json/jAgent.ml
+++ b/petanque/json/jAgent.ml
@@ -8,22 +8,6 @@ module Inspect = struct
 end
 
 (* The typical protocol dance *)
-
-(* What a mess result stuff is, we need this in case result is installed, as
-   then the types below will be referenced as plain result ... *)
-module Stdlib = struct
-  module Result = struct
-    include Stdlib.Result
-
-    type ('a, 'e) t = [%import: ('a, 'e) Stdlib.Result.t] [@@deriving yojson]
-  end
-end
-
-module Result = Stdlib.Result
-
-(* ppx_import < 1.10 hack, for some reason it gets confused with the aliases. *)
-module Result_ = Stdlib.Result
-
 module Error = struct
   type t = [%import: Petanque.Agent.Error.t] [@@deriving yojson]
 end
@@ -36,57 +20,24 @@ module Run_result = struct
   type 'a t = [%import: 'a Petanque.Agent.Run_result.t] [@@deriving yojson]
 end
 
+(* Both are needed as of today *)
+module Stdlib = Lsp.JStdlib
+module Result = Stdlib.Result
+
 module R = struct
-  type 'a t =
-    [%import:
-      ('a Petanque.Agent.R.t
-      [@with
-        Stdlib.Result.t := Result_.t;
-        Result.t := Result_.t])]
-  [@@deriving yojson]
+  type 'a t = [%import: 'a Petanque.Agent.R.t] [@@deriving yojson]
 end
 
 module Goals = struct
   type t = string Lsp.JCoq.Goals.reified_pp option [@@deriving yojson]
 end
 
-module Lang = struct
-  module Range = struct
-    type t = Lsp.JLang.Range.t [@@deriving yojson]
-  end
-
-  module With_range = struct
-    type 'a t = [%import: ('a Lang.With_range.t[@with Lang.Range.t := Range.t])]
-    [@@deriving yojson]
-  end
-
-  module Ast = struct
-    module Name = struct
-      type t = [%import: Lang.Ast.Name.t] [@@deriving yojson]
-    end
-
-    module Info = struct
-      type t =
-        [%import:
-          (Lang.Ast.Info.t
-          [@with
-            Lang.Range.t := Range.t;
-            Lang.With_range.t := With_range.t])]
-      [@@deriving yojson]
-    end
-  end
-end
+module Lang = Lsp.JLang
 
 module Premise = struct
   module Info = struct
     type t = [%import: Petanque.Agent.Premise.Info.t] [@@deriving yojson]
   end
 
-  type t =
-    [%import:
-      (Petanque.Agent.Premise.t
-      [@with
-        Stdlib.Result.t := Result_.t;
-        Result.t := Result_.t])]
-  [@@deriving yojson]
+  type t = [%import: Petanque.Agent.Premise.t] [@@deriving yojson]
 end
diff --git a/petanque/json_shell/protocol_shell.ml b/petanque/json_shell/protocol_shell.ml
index 4f4bb4d7..12acda71 100644
--- a/petanque/json_shell/protocol_shell.ml
+++ b/petanque/json_shell/protocol_shell.ml
@@ -6,7 +6,6 @@
 (************************************************************************)
 
 open Petanque_json
-open JAgent
 
 (** [set_workspace { debug; root }] sets the current workspace to the directory
     specified in [root] *)
@@ -47,7 +46,8 @@ module TableOfContents = struct
   end
 
   module Response = struct
-    type t = (string * Lang.Ast.Info.t list option) list [@@deriving yojson]
+    type t = (string * Lsp.JLang.Ast.Info.t list option) list
+    [@@deriving yojson]
   end
 
   module Handler = struct