diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -0,0 +1,3 @@
+### 2.0.15
+
++ [timeValToIso8601](https://hackage.haskell.org/package/gi-glib/docs/GI-GLib-Structs-TimeVal.html#v:timeValToIso8601) has a nullable return value.
diff --git a/GLib.overrides b/GLib.overrides
--- a/GLib.overrides
+++ b/GLib.overrides
@@ -30,6 +30,9 @@
 ignore base64_encode_step
 ignore base64_encode_close
 
+# Return type (correctly) marked as nullable since 2.54 at least.
+set-attr GLib/TimeVal/to_iso8601/@return-value nullable 1
+
 if windows
    # Windows only macros in glib/gfileutils.h
    set-attr GLib/file_get_contents c:identifier g_file_get_contents_utf8
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Documentation
 Autogenerated documentation for this package can be found at
 
-[https://hackage.haskell.org/package/gi-glib-2.0.14/docs/GI-GLib.html](https://hackage.haskell.org/package/gi-glib-2.0.14/docs/GI-GLib.html)
+[https://hackage.haskell.org/package/gi-glib-2.0.15/docs/GI-GLib.html](https://hackage.haskell.org/package/gi-glib-2.0.15/docs/GI-GLib.html)
 
 For general documentation on using [haskell-gi](https://github.com/haskell-gi/haskell-gi) based bindings, see [the project page](https://github.com/haskell-gi/haskell-gi) or [the Wiki](https://github.com/haskell-gi/haskell-gi/wiki).
diff --git a/gi-glib.cabal b/gi-glib.cabal
--- a/gi-glib.cabal
+++ b/gi-glib.cabal
@@ -1,5 +1,5 @@
 name:                 gi-glib
-version:              2.0.14
+version:              2.0.15
 synopsis:             GLib bindings
 description:          Bindings for GLib, autogenerated by haskell-gi.
 homepage:             https://github.com/haskell-gi/haskell-gi