From 118ef67e0743b3b61baab8737e152f31d48b3ddc Mon Sep 17 00:00:00 2001
From: DavHau <hsngrmpf+github@gmail.com>
Date: Thu, 22 Apr 2021 11:06:03 +0700
Subject: [PATCH 1/3] nixFlakes: enable flakes

---
 pkgs/tools/package-management/nix/default.nix | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index ac61a64180d..46f11322484 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -227,6 +227,13 @@ in rec {
     inherit storeDir stateDir confDir boehmgc;
   });
 
-  nixFlakes = nixUnstable;
+  nixFlakes = callPackage ({ makeWrapper, runCommand, ... }:
+    runCommand "nix-flakes" { buildInputs = [ makeWrapper ]; } ''
+      mkdir -p $out/bin
+        for bin in ${nixUnstable}/bin/*; do
+          makeWrapper $bin $out/bin/$(basename $bin) \
+            --suffix NIX_CONFIG "\n" "experimental-features = nix-command flakes"
+        done;
+    '') {};
 
 }

From f94876e77b7de2bfd0960cd53fedf7bac7d998d1 Mon Sep 17 00:00:00 2001
From: DavHau <hsngrmpf+github@gmail.com>
Date: Thu, 22 Apr 2021 12:31:41 +0700
Subject: [PATCH 2/3] nixFlakes: enable flakes,nix-command via patch

---
 pkgs/tools/package-management/nix/default.nix      | 11 +++--------
 .../package-management/nix/enable-flakes.patch     | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 8 deletions(-)
 create mode 100644 pkgs/tools/package-management/nix/enable-flakes.patch

diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index 46f11322484..fa088e04fe5 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -227,13 +227,8 @@ in rec {
     inherit storeDir stateDir confDir boehmgc;
   });
 
-  nixFlakes = callPackage ({ makeWrapper, runCommand, ... }:
-    runCommand "nix-flakes" { buildInputs = [ makeWrapper ]; } ''
-      mkdir -p $out/bin
-        for bin in ${nixUnstable}/bin/*; do
-          makeWrapper $bin $out/bin/$(basename $bin) \
-            --suffix NIX_CONFIG "\n" "experimental-features = nix-command flakes"
-        done;
-    '') {};
+  nixFlakes = nixUnstable.overrideAttrs (prev: {
+    patches = (prev.patches or []) ++ [ ./enable-flakes.patch ];
+  });
 
 }
diff --git a/pkgs/tools/package-management/nix/enable-flakes.patch b/pkgs/tools/package-management/nix/enable-flakes.patch
new file mode 100644
index 00000000000..998067449b7
--- /dev/null
+++ b/pkgs/tools/package-management/nix/enable-flakes.patch
@@ -0,0 +1,14 @@
+diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh
+index 3e4ead76c..81d407236 100644
+--- a/src/libstore/globals.hh
++++ b/src/libstore/globals.hh
+@@ -923,7 +923,8 @@ public:
+           value.
+           )"};
+ 
+-    Setting<Strings> experimentalFeatures{this, {}, "experimental-features",
++    Setting<Strings> experimentalFeatures{
++        this, {"flakes", "nix-command"}, "experimental-features",
+         "Experimental Nix features to enable."};
+ 
+     bool isExperimentalFeatureEnabled(const std::string & name);

From 88658813192ae0348aa307d592ac2d52398ba669 Mon Sep 17 00:00:00 2001
From: DavHau <hsngrmpf+github@gmail.com>
Date: Tue, 4 May 2021 18:15:27 +0700
Subject: [PATCH 3/3] nixExperimental: init

---
 pkgs/tools/package-management/nix/default.nix      |  4 ++++
 .../nix/enable-all-experimental.patch              | 14 ++++++++++++++
 pkgs/top-level/all-packages.nix                    |  3 ++-
 3 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 pkgs/tools/package-management/nix/enable-all-experimental.patch

diff --git a/pkgs/tools/package-management/nix/default.nix b/pkgs/tools/package-management/nix/default.nix
index fa088e04fe5..a8dd048be02 100644
--- a/pkgs/tools/package-management/nix/default.nix
+++ b/pkgs/tools/package-management/nix/default.nix
@@ -227,6 +227,10 @@ in rec {
     inherit storeDir stateDir confDir boehmgc;
   });
 
+  nixExperimental = nixUnstable.overrideAttrs (prev: {
+    patches = (prev.patches or []) ++ [ ./enable-all-experimental.patch ];
+  });
+
   nixFlakes = nixUnstable.overrideAttrs (prev: {
     patches = (prev.patches or []) ++ [ ./enable-flakes.patch ];
   });
diff --git a/pkgs/tools/package-management/nix/enable-all-experimental.patch b/pkgs/tools/package-management/nix/enable-all-experimental.patch
new file mode 100644
index 00000000000..1712b7295a5
--- /dev/null
+++ b/pkgs/tools/package-management/nix/enable-all-experimental.patch
@@ -0,0 +1,14 @@
+diff --git a/src/libstore/globals.cc b/src/libstore/globals.cc
+index d3b27d7be..e7d002e1d 100644
+--- a/src/libstore/globals.cc
++++ b/src/libstore/globals.cc
+@@ -172,8 +172,7 @@ MissingExperimentalFeature::MissingExperimentalFeature(std::string feature)
+ 
+ void Settings::requireExperimentalFeature(const std::string & name)
+ {
+-    if (!isExperimentalFeatureEnabled(name))
+-        throw MissingExperimentalFeature(name);
++    return;
+ }
+ 
+ bool Settings::isWSL1()
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 04effbffbd3..6437e2414fa 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -30099,7 +30099,8 @@ in
     nix
     nixStable
     nixUnstable
-    nixFlakes;
+    nixFlakes
+    nixExperimental;
 
   nixStatic = pkgsStatic.nix;