diff --git a/tests/fixtures/flake-direct-nativeBuildInput/flake.lock b/tests/fixtures/flake-direct-nativeBuildInput/flake.lock
new file mode 100644
index 0000000..eff9f1c
--- /dev/null
+++ b/tests/fixtures/flake-direct-nativeBuildInput/flake.lock
@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1692799911,
+        "narHash": "sha256-3eihraek4qL744EvQXsK1Ha6C3CR7nnT8X2qWap4RNk=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "f9e7cf818399d17d347f847525c5a5a8032e4e44",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1688392541,
+        "narHash": "sha256-lHrKvEkCPTUO+7tPfjIcb7Trk6k31rz18vkyqmkeJfY=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "ea4c80b39be4c09702b0cb3b42eab59e2ba4f24b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-22.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/tests/fixtures/flake-direct-nativeBuildInput/flake.nix b/tests/fixtures/flake-direct-nativeBuildInput/flake.nix
new file mode 100644
index 0000000..b8d2b05
--- /dev/null
+++ b/tests/fixtures/flake-direct-nativeBuildInput/flake.nix
@@ -0,0 +1,38 @@
+{
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-22.11";
+  inputs.flake-utils.url = "github:numtide/flake-utils";
+
+  outputs = { flake-utils, nixpkgs, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+
+        pkg1 = pkgs.stdenv.mkDerivation {
+          name = "pkg1";
+          src = ./pkg1;
+          buildInputs = [ pkgs.bash ];
+          installPhase = ''
+            mkdir -p $out/bin
+            cp $src/* $out/bin
+          '';
+        };
+
+        pkg2 = pkgs.stdenv.mkDerivation {
+          name = "pkg2";
+          src = ./pkg2;
+          nativeBuildInputs = [ pkgs.bash pkg1 ];
+          buildPhase = ''
+            pkg1
+          '';
+          installPhase = ''
+            mkdir -p $out/bin
+            cp $src/* $out/bin
+          '';
+        };
+
+      in
+      {
+        packages.default = pkg2;
+      }
+    );
+}
diff --git a/tests/fixtures/flake-direct-nativeBuildInput/pkg1/pkg1 b/tests/fixtures/flake-direct-nativeBuildInput/pkg1/pkg1
new file mode 100755
index 0000000..50eef3d
--- /dev/null
+++ b/tests/fixtures/flake-direct-nativeBuildInput/pkg1/pkg1
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+echo "pkg1"
\ No newline at end of file
diff --git a/tests/fixtures/flake-direct-nativeBuildInput/pkg2/pkg2 b/tests/fixtures/flake-direct-nativeBuildInput/pkg2/pkg2
new file mode 100755
index 0000000..40d4fa8
--- /dev/null
+++ b/tests/fixtures/flake-direct-nativeBuildInput/pkg2/pkg2
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+echo "pkg2"
\ No newline at end of file
diff --git a/tests/fixtures/flake-three-levels/flake.lock b/tests/fixtures/flake-three-levels/flake.lock
new file mode 100644
index 0000000..eff9f1c
--- /dev/null
+++ b/tests/fixtures/flake-three-levels/flake.lock
@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1692799911,
+        "narHash": "sha256-3eihraek4qL744EvQXsK1Ha6C3CR7nnT8X2qWap4RNk=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "f9e7cf818399d17d347f847525c5a5a8032e4e44",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1688392541,
+        "narHash": "sha256-lHrKvEkCPTUO+7tPfjIcb7Trk6k31rz18vkyqmkeJfY=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "ea4c80b39be4c09702b0cb3b42eab59e2ba4f24b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-22.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/tests/fixtures/flake-three-levels/flake.nix b/tests/fixtures/flake-three-levels/flake.nix
new file mode 100644
index 0000000..429cc34
--- /dev/null
+++ b/tests/fixtures/flake-three-levels/flake.nix
@@ -0,0 +1,50 @@
+{
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-22.11";
+  inputs.flake-utils.url = "github:numtide/flake-utils";
+
+  outputs = { flake-utils, nixpkgs, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+
+        pkg1 = pkgs.stdenv.mkDerivation {
+          name = "pkg1";
+          src = ./pkg1;
+          buildInputs = [ pkgs.bash ];
+          installPhase = ''
+            mkdir -p $out/bin
+            cp $src/* $out/bin
+          '';
+        };
+
+        pkg2 = pkgs.stdenv.mkDerivation {
+          name = "pkg2";
+          src = ./pkg2;
+          buildInputs = [ pkgs.bash pkg1 ];
+          buildPhase = ''
+            pkg1
+          '';
+          installPhase = ''
+            mkdir -p $out/bin
+            cp $src/* $out/bin
+          '';
+        };
+
+        pkg3 = pkgs.stdenv.mkDerivation {
+          name = "pkg3";
+          src = ./pkg3;
+          buildInputs = [ pkgs.bash pkg2 ];
+          buildPhase = ''
+            pkg2
+          '';
+          installPhase = ''
+            mkdir -p $out/bin
+            cp $src/* $out/bin
+          '';
+        };
+      in
+      {
+        packages.default = pkg3;
+      }
+    );
+}
diff --git a/tests/fixtures/flake-three-levels/pkg1/pkg1 b/tests/fixtures/flake-three-levels/pkg1/pkg1
new file mode 100755
index 0000000..50eef3d
--- /dev/null
+++ b/tests/fixtures/flake-three-levels/pkg1/pkg1
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+echo "pkg1"
\ No newline at end of file
diff --git a/tests/fixtures/flake-three-levels/pkg2/pkg2 b/tests/fixtures/flake-three-levels/pkg2/pkg2
new file mode 100755
index 0000000..40d4fa8
--- /dev/null
+++ b/tests/fixtures/flake-three-levels/pkg2/pkg2
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+echo "pkg2"
\ No newline at end of file
diff --git a/tests/fixtures/flake-three-levels/pkg3/pkg3 b/tests/fixtures/flake-three-levels/pkg3/pkg3
new file mode 100755
index 0000000..cb076a7
--- /dev/null
+++ b/tests/fixtures/flake-three-levels/pkg3/pkg3
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+echo "pkg3"