diff --git a/src/format/opamTypes.mli b/src/format/opamTypes.mli
index ac5762f9e46..9a19f2c0d1b 100644
--- a/src/format/opamTypes.mli
+++ b/src/format/opamTypes.mli
@@ -216,7 +216,7 @@ type 'a highlevel_action = [
     changed state or version *)
 type 'a inst_action = [
   | `Install of 'a
-  | `Change of 'a * 'a * [ `Up | `Down ]
+  | `Change of [ `Up | `Down ] * 'a * 'a
 ]
 
 (** Used when applying solutions, separates build from install *)
diff --git a/src/solver/opamActionGraph.ml b/src/solver/opamActionGraph.ml
index 84048765072..71d31299ba2 100644
--- a/src/solver/opamActionGraph.ml
+++ b/src/solver/opamActionGraph.ml
@@ -33,12 +33,12 @@ let name_of_action = function
   | `Build _ -> "build"
 
 let symbol_of_action = function
-  | `Remove _ -> "\xe2\x8a\x98 "
-  | `Install _ -> "\xe2\x88\x97 "
-  | `Change (`Up,_,_) -> "\xe2\x86\x97 "
-  | `Change (`Down,_,_) -> "\xe2\x86\x98 "
-  | `Reinstall _ -> "\xe2\x86\xbb "
-  | `Build _ -> "\xe2\x88\x97 "
+  | `Remove _ -> "\xe2\x8a\x98 " (* U+2298 *)
+  | `Install _ -> "\xe2\x88\x97 " (* U+2217 *)
+  | `Change (`Up,_,_) -> "\xe2\x86\x97 " (* U+2197 *)
+  | `Change (`Down,_,_) -> "\xe2\x86\x98 " (* U+2198 *)
+  | `Reinstall _ -> "\xe2\x86\xbb " (* U+21BB *)
+  | `Build _ -> "\xce\xbb " (* U+039B *)
 
 let action_strings ?utf8 a =
   if utf8 = None && (OpamConsole.utf8 ()) || utf8 = Some true