From 39497df1eff6b5ebea1b4dc35dc0814e074a5aec Mon Sep 17 00:00:00 2001
From: Daiderd Jordan <daiderd@gmail.com>
Date: Fri, 23 Jun 2017 20:01:36 +0200
Subject: [PATCH 1/2] erlang: change default R18 -> R19

---
 pkgs/top-level/beam-packages.nix | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/pkgs/top-level/beam-packages.nix b/pkgs/top-level/beam-packages.nix
index 46b0d12a5e9..acdbea67332 100644
--- a/pkgs/top-level/beam-packages.nix
+++ b/pkgs/top-level/beam-packages.nix
@@ -7,10 +7,10 @@ rec {
   interpreters = rec {
 
     # R18 is the default version.
-    erlang = erlangR18; # The main switch to change default Erlang version.
-    erlang_odbc = erlangR18_odbc;
-    erlang_javac = erlangR18_javac;
-    erlang_odbc_javac = erlangR18_odbc_javac;
+    erlang = erlangR19; # The main switch to change default Erlang version.
+    erlang_odbc = erlangR19_odbc;
+    erlang_javac = erlangR19_javac;
+    erlang_odbc_javac = erlangR19_odbc_javac;
 
     # These are standard Erlang versions, using the generic builder.
     erlangR16 = lib.callErlang ../development/interpreters/erlang/R16.nix {};

From dc1ae6f18d719fba92123d33b1d30bcadc2b31cb Mon Sep 17 00:00:00 2001
From: Daiderd Jordan <daiderd@gmail.com>
Date: Sat, 24 Jun 2017 01:51:00 +0200
Subject: [PATCH 2/2] erlang: use R18 for packages that don't work with R19

---
 pkgs/top-level/all-packages.nix | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index b99290127f3..50990745561 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -6001,7 +6001,9 @@ with pkgs;
   inherit (beam.packages.erlang)
     rebar rebar3-open rebar3
     hexRegistrySnapshot fetchHex beamPackages
-    hex2nix cuter relxExe;
+    hex2nix cuter;
+
+  inherit (beam.packages.erlangR18) relxExe;
 
   groovy = callPackage ../development/interpreters/groovy { };
 
@@ -11460,7 +11462,9 @@ with pkgs;
 
   xwayland = callPackage ../servers/x11/xorg/xwayland.nix { };
 
-  yaws = callPackage ../servers/http/yaws { };
+  yaws = callPackage ../servers/http/yaws {
+    erlang = erlangR18;
+  };
 
   zabbix = recurseIntoAttrs (callPackages ../servers/monitoring/zabbix {});
 
@@ -16423,7 +16427,9 @@ with pkgs;
 
   winswitch = callPackage ../tools/X11/winswitch { };
 
-  wings = callPackage ../applications/graphics/wings { };
+  wings = callPackage ../applications/graphics/wings {
+    erlang = erlangR18;
+  };
 
   wireguard = callPackage ../os-specific/linux/wireguard { };