diff --git a/pkgs/development/compilers/mono/6.nix b/pkgs/development/compilers/mono/6.nix
index 0157fa7b7f68..04028648a255 100644
--- a/pkgs/development/compilers/mono/6.nix
+++ b/pkgs/development/compilers/mono/6.nix
@@ -2,8 +2,8 @@
 
 callPackage ./generic.nix ({
   inherit Foundation libobjc;
-  version = "6.0.0.313";
+  version = "6.12.0.90";
   srcArchiveSuffix = "tar.xz";
-  sha256 = "0l0cd6q5xh1vdm6zr78rkfqdsmrgzanjgpxvgig0pyd3glfyjim9";
+  sha256 = "1b6d0926rd0nkmsppwjgmwsxx1479jjvr1gm7zwk64siml15rpji";
   enableParallelBuilding = true;
 })
diff --git a/pkgs/development/compilers/mono/generic.nix b/pkgs/development/compilers/mono/generic.nix
index c510f372666a..ca3b31478070 100644
--- a/pkgs/development/compilers/mono/generic.nix
+++ b/pkgs/development/compilers/mono/generic.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, bison, pkgconfig, glib, gettext, perl, libgdiplus, libX11, callPackage, ncurses, zlib, withLLVM ? false, cacert, Foundation, libobjc, python, version, sha256, autoconf, libtool, automake, cmake, which
+{ stdenv, fetchurl, bison, pkgconfig, glib, gettext, perl, libgdiplus, libX11, callPackage, ncurses, zlib, withLLVM ? false, cacert, Foundation, libobjc, python3, version, sha256, autoconf, libtool, automake, cmake, which
 , gnumake42
 , enableParallelBuilding ? true
 , srcArchiveSuffix ? "tar.bz2"
@@ -19,7 +19,7 @@ stdenv.mkDerivation rec {
 
   nativeBuildInputs = [ gnumake42 ];
   buildInputs =
-    [ bison pkgconfig glib gettext perl libgdiplus libX11 ncurses zlib python autoconf libtool automake cmake which
+    [ bison pkgconfig glib gettext perl libgdiplus libX11 ncurses zlib python3 autoconf libtool automake cmake which
     ]
     ++ (stdenv.lib.optionals stdenv.isDarwin [ Foundation libobjc ]);