diff --git a/index/gl/globe_3d.toml b/index/gl/globe_3d.toml
index b2075df4..e425f823 100644
--- a/index/gl/globe_3d.toml
+++ b/index/gl/globe_3d.toml
@@ -18,6 +18,5 @@ project-files = ["globe_3d.gpr"]
     [20180111.gpr-externals]
     OS_Kind = ["linux", "macosx", "win32"]
 
-    [20180111.gpr-set-externals.OS_Kind.'case(os)']
-    linux = "linux"
-    '...' = ""
+    [20180111.gpr-set-externals.'case(os)']
+    linux = { OS_Kind = "linux" }
diff --git a/index/gn/gnatcoll.toml b/index/gn/gnatcoll.toml
index e7db4adf..e7d7d5f4 100644
--- a/index/gn/gnatcoll.toml
+++ b/index/gn/gnatcoll.toml
@@ -14,10 +14,10 @@ maintainers = ["alejandro@mosteo.com"]
     BUILD = "PROD"
     LIBRARY_TYPE = "static-pic"
 
-        [general.gpr-set-externals.GNATCOLL_OS.'case(os)']
-        linux = "unix"
-        macos = "osx"
-        windows = "windows"
+        [general.gpr-set-externals.'case(os)']
+        linux = { GNATCOLL_OS = "unix" }
+        macos = { GNATCOLL_OS = "osx" }
+        windows = { GNATCOLL_OS = "windows" }
 
 [2018]
 origin = "http://mirrors.cdn.adacore.com/art/5b0819dfc7a447df26c27a99"
diff --git a/index/gn/gnatcoll_slim.toml b/index/gn/gnatcoll_slim.toml
index b391d90e..8fa52601 100644
--- a/index/gn/gnatcoll_slim.toml
+++ b/index/gn/gnatcoll_slim.toml
@@ -16,10 +16,10 @@ project-files = ["gnatcoll.gpr"]
     BUILD = "PROD"
     LIBRARY_TYPE = "static-pic"
 
-        [general.gpr-set-externals.GNATCOLL_OS.'case(os)']
-        linux = "unix"
-        macos = "osx"
-        windows = "windows"
+        [general.gpr-set-externals.'case(os)']
+        linux = { GNATCOLL_OS = "unix" }
+        macos = { GNATCOLL_OS = "osx" }
+        windows = { GNATCOLL_OS = "windows" }
 
 [20180425]
 origin = "git+https://github.com/alire-project/gnatcoll-core.git@81bc37d7548fe40024eb0f647df65ec42f65443b"
diff --git a/index/gn/gnatcoll_strings.toml b/index/gn/gnatcoll_strings.toml
index 2401e471..9fcdf165 100644
--- a/index/gn/gnatcoll_strings.toml
+++ b/index/gn/gnatcoll_strings.toml
@@ -16,10 +16,10 @@ project-files = ["gnatcoll.gpr"]
     BUILD = "PROD"
     LIBRARY_TYPE = "static-pic"
 
-        [general.gpr-set-externals.GNATCOLL_OS.'case(os)']
-        linux = "unix"
-        macos = "osx"
-        windows = "windows"
+        [general.gpr-set-externals.'case(os)']
+        linux = { GNATCOLL_OS = "unix" }
+        macos = { GNATCOLL_OS = "osx" }
+        windows = { GNATCOLL_OS = "windows" }
 
 [20180425]
 origin = "git+https://github.com/alire-project/gnatcoll-core.git@7823e31add7133b9fbc6e037d9986a823e840dc0"
diff --git a/index/li/libadacrypt.toml b/index/li/libadacrypt.toml
index 2332b35b..fbc00ddc 100644
--- a/index/li/libadacrypt.toml
+++ b/index/li/libadacrypt.toml
@@ -14,11 +14,9 @@ project-files = ["libadacrypt.gpr"]
     system = ["unix", "windows"]
     mode = ["debug", "release"]
 
-    [general.gpr-set-externals]
-        [general.gpr-set-externals.system.'case(os)']
-        linux = "unix"
-        windows = "windows"
-        '...' = ""
+    [general.gpr-set-externals.'case(os)']
+        linux = { system = "unix" }
+        windows = { system = "windows" }
 
 ['0.8.7']
 origin = "git+https://github.com/alire-project/Ada-Crypto-Library.git@33d15283abbc6d8a51d717de2bd822e026710c0d"
diff --git a/index/op/openglada.toml b/index/op/openglada.toml
index 13eaf1f3..90d1d269 100644
--- a/index/op/openglada.toml
+++ b/index/op/openglada.toml
@@ -17,9 +17,8 @@ executables = ["gl_test-opengl3", "gl_test-context", "gl_test-vbos",
     Mode = ["debug", "release"]
     Auto_Exceptions = ["enabled", "disabled"]
 
-    [general.gpr-set-externals.Windowing_System.'case(os)']
-    linux = "x11"
-    '...' = ""
+    [general.gpr-set-externals.'case(os)']
+    linux = { Windowing_System = "x11" }
 
 ['0.6']
 origin = "git+https://github.com/flyx/OpenGLAda.git@54a7a50cebab2cba0262c7f59b927e9ddf6e4649"
diff --git a/index/sd/sdlada.toml b/index/sd/sdlada.toml
index 40bca4fc..bcc85e66 100644
--- a/index/sd/sdlada.toml
+++ b/index/sd/sdlada.toml
@@ -13,9 +13,8 @@ project-files = ["build/gnat/sdlada.gpr"]
     [general.gpr-set-externals]
     SDL_MODE = "release"
 
-        [general.gpr-set-externals.SDL_PLATFORM.'case(os)']
-        linux = "linux"
-        '...' = ""
+        [general.gpr-set-externals.'case(os)']
+        linux = { SDL_PLATFORM = "linux" }
 
     [general.available.'case(os)']
     linux = true