diff --git a/pkgs/development/beam-modules/default.nix b/pkgs/development/beam-modules/default.nix
index 63d046c7b47e..eb9353a4a637 100644
--- a/pkgs/development/beam-modules/default.nix
+++ b/pkgs/development/beam-modules/default.nix
@@ -41,7 +41,7 @@ let
         buildMix = callPackage ./build-mix.nix {};
 
         # BEAM-based languages.
-        elixir = elixir_1_7;
+        elixir = elixir_1_9;
 
         elixir_1_9 = lib.callElixir ../interpreters/elixir/1.9.nix {
           inherit rebar erlang;
diff --git a/pkgs/servers/amqp/rabbitmq-server/default.nix b/pkgs/servers/amqp/rabbitmq-server/default.nix
index 7e5714804190..00f83cba8db2 100644
--- a/pkgs/servers/amqp/rabbitmq-server/default.nix
+++ b/pkgs/servers/amqp/rabbitmq-server/default.nix
@@ -8,6 +8,7 @@ stdenv.mkDerivation rec {
 
   version = "3.7.16";
 
+  # when updating, consider bumping elixir version in all-packages.nix
   src = fetchurl {
     url = "https://github.com/rabbitmq/rabbitmq-server/releases/download/v${version}/${name}.tar.xz";
     sha256 = "12s1s4zz3fxvb5ah5v6gmaq1kgd41pv9nahsdswa7svbgdc8lykz";
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index fca26b3a7e38..52fcdb2167d4 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -14744,7 +14744,7 @@ in
 
   rabbitmq-server = callPackage ../servers/amqp/rabbitmq-server {
     inherit (darwin.apple_sdk.frameworks) AppKit Carbon Cocoa;
-    elixir = elixir_1_6;
+    elixir = elixir_1_8;
     erlang = erlang_nox;
   };