diff --git a/flake.nix b/flake.nix
index 7c827e2..5cc269c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: { jre = prev.adoptopenjdk-hotspot-bin-11; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }

diff --git a/flake.nix b/flake.nix
index 7c827e2..5cc269c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: { jre = prev.adoptopenjdk-hotspot-bin-11; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }
diff --git a/shell.nix b/shell.nix
index 600ee3f..bc59c53 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,6 +1,11 @@
-{ pkgs ? import <nixpkgs> { } }:
+{ pkgs ? import <nixpkgs> {
+  overlays = [
+    (final: prev: rec {
+      jre = prev.adoptopenjdk-hotspot-bin-11;
+      jdk = jre;
+    })
+  ];
+} }:
 
 with pkgs;
-mkShell {
- buildInputs = [ jre ammonite coursier bloop sbt scalafmt ];
- }
+mkShell { buildInputs = [ jre ammonite coursier bloop sbt scalafmt ]; }

diff --git a/flake.nix b/flake.nix
index 7c827e2..5cc269c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: { jre = prev.adoptopenjdk-hotspot-bin-11; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }
diff --git a/shell.nix b/shell.nix
index 600ee3f..bc59c53 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,6 +1,11 @@
-{ pkgs ? import <nixpkgs> { } }:
+{ pkgs ? import <nixpkgs> {
+  overlays = [
+    (final: prev: rec {
+      jre = prev.adoptopenjdk-hotspot-bin-11;
+      jdk = jre;
+    })
+  ];
+} }:
 
 with pkgs;
-mkShell {
- buildInputs = [ jre ammonite coursier bloop sbt scalafmt ];
- }
+mkShell { buildInputs = [ jre ammonite coursier bloop sbt scalafmt ]; }
diff --git a/src/main/g8/flake.nix b/src/main/g8/flake.nix
index e119b6c..5cc269c 100644
--- a/src/main/g8/flake.nix
+++ b/src/main/g8/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.\${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: rec { jre = prev.adoptopenjdk-hotspot-bin-$java_version$; jdk = jre; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }

diff --git a/flake.nix b/flake.nix
index 7c827e2..5cc269c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: { jre = prev.adoptopenjdk-hotspot-bin-11; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }
diff --git a/shell.nix b/shell.nix
index 600ee3f..bc59c53 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,6 +1,11 @@
-{ pkgs ? import <nixpkgs> { } }:
+{ pkgs ? import <nixpkgs> {
+  overlays = [
+    (final: prev: rec {
+      jre = prev.adoptopenjdk-hotspot-bin-11;
+      jdk = jre;
+    })
+  ];
+} }:
 
 with pkgs;
-mkShell {
- buildInputs = [ jre ammonite coursier bloop sbt scalafmt ];
- }
+mkShell { buildInputs = [ jre ammonite coursier bloop sbt scalafmt ]; }
diff --git a/src/main/g8/flake.nix b/src/main/g8/flake.nix
index e119b6c..5cc269c 100644
--- a/src/main/g8/flake.nix
+++ b/src/main/g8/flake.nix
@@ -8,11 +8,15 @@
 
   outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.\${system};
-      in {
-        devShell = import ./shell.nix {
-          pkgs = pkgs.extend
-            (final: prev: rec { jre = prev.adoptopenjdk-hotspot-bin-$java_version$; jdk = jre; });
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            (final: prev: rec {
+              jre = prev.adoptopenjdk-hotspot-bin-11;
+              jdk = jre;
+            })
+          ];
         };
-      });
+      in { devShell = import ./shell.nix { inherit pkgs; }; });
 }
diff --git a/src/main/g8/shell.nix b/src/main/g8/shell.nix
index 600ee3f..bc59c53 100644
--- a/src/main/g8/shell.nix
+++ b/src/main/g8/shell.nix
@@ -1,6 +1,11 @@
-{ pkgs ? import <nixpkgs> { } }:
+{ pkgs ? import <nixpkgs> {
+  overlays = [
+    (final: prev: rec {
+      jre = prev.adoptopenjdk-hotspot-bin-11;
+      jdk = jre;
+    })
+  ];
+} }:
 
 with pkgs;
-mkShell {
- buildInputs = [ jre ammonite coursier bloop sbt scalafmt ];
- }
+mkShell { buildInputs = [ jre ammonite coursier bloop sbt scalafmt ]; }