diff --git a/.config/selfci/.gitignore b/.config/selfci/.gitignore
new file mode 100644
index 0000000..bd5d334
--- /dev/null
+++ b/.config/selfci/.gitignore
@@ -0,0 +1 @@
+local.yaml
diff --git a/.config/selfci/ci.sh b/.config/selfci/ci.sh
new file mode 100755
index 0000000..5afcf23
--- /dev/null
+++ b/.config/selfci/ci.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+set -eou pipefail
+
+function job_lint() {
+  selfci step start "treefmt"
+  if ! treefmt --ci ; then
+    selfci step fail
+  fi
+}
+
+function job_checks() {
+    selfci step start "flake check"
+    nix flake check -L
+}
+
+case "$SELFCI_JOB_NAME" in
+  main)
+    selfci job start "lint"
+    selfci job start "checks"
+    ;;
+  checks)
+    job_checks
+    ;;
+  lint)
+    export -f job_lint
+    nix develop -c bash -c "job_lint"
+    ;;
+  *)
+    echo "Unknown job: $SELFCI_JOB_NAME"
+    exit 1
+esac
diff --git a/.config/selfci/ci.yaml b/.config/selfci/ci.yaml
new file mode 100644
index 0000000..8867188
--- /dev/null
+++ b/.config/selfci/ci.yaml
@@ -0,0 +1,7 @@
+job:
+  clone-mode: partial
+  command: ./.config/selfci/ci.sh
+
+mq:
+  base-branch: master
+  merge-style: rebase
diff --git a/bin/bootstrap.flake.nix b/bin/bootstrap.flake.nix
index 5f5a032..e16907d 100644
--- a/bin/bootstrap.flake.nix
+++ b/bin/bootstrap.flake.nix
@@ -18,7 +18,8 @@
     flake-utils.lib.eachDefaultSystem (
       system:
       let
-        flakeboxLib = flakebox.lib.${system} { };
+        pkgs = nixpkgs.legacyPackages.${system};
+        flakeboxLib = flakebox.lib.mkLib pkgs { };
       in
       {
         devShells = {
diff --git a/checks/default.nix b/checks/default.nix
index bc48bbc..8becd51 100644
--- a/checks/default.nix
+++ b/checks/default.nix
@@ -19,6 +19,8 @@ onlyDrvs (
       workspaceSanity = callPackage ./workspace-sanity { };
       workspaceCross = callPackage ./workspace-cross-compile { inherit full; };
       customStdenv = callPackage ./custom-stdenv { };
+      nextest = callPackage ./nextest { };
+      mergeArgsTests = callPackage ./mergeArgs-tests.nix { };
     }
   )
 )
diff --git a/checks/mergeArgs-tests.nix b/checks/mergeArgs-tests.nix
new file mode 100644
index 0000000..8b2471d
--- /dev/null
+++ b/checks/mergeArgs-tests.nix
@@ -0,0 +1,80 @@
+{ pkgs, flakeboxLib }:
+let
+  inherit (pkgs) lib;
+  mergeArgs = flakeboxLib.mergeArgs;
+
+  assertEq =
+    name: actual: expected:
+    lib.assertMsg (
+      actual == expected
+    ) "${name}: expected ${builtins.toJSON expected}, got ${builtins.toJSON actual}";
+
+  r1 = mergeArgs { buildInputs = [ 1 ]; } { buildInputs = [ 2 ]; };
+  r2 = mergeArgs { nativeBuildInputs = [ 1 ]; } { nativeBuildInputs = [ 2 ]; };
+  r3 = mergeArgs { packages = [ 1 ]; } { packages = [ 2 ]; };
+  r4 =
+    mergeArgs
+      {
+        env = {
+          A = "1";
+        };
+      }
+      {
+        env = {
+          B = "2";
+        };
+      };
+  r5 =
+    mergeArgs
+      {
+        env = {
+          A = "1";
+        };
+      }
+      {
+        env = {
+          A = "2";
+        };
+      };
+  r6 = mergeArgs { } { buildInputs = [ 1 ]; };
+  r7 = mergeArgs { buildInputs = [ 1 ]; } { };
+  r8 = mergeArgs { } {
+    env = {
+      A = "1";
+    };
+  };
+  r9 = mergeArgs {
+    env = {
+      A = "1";
+    };
+  } { };
+  r10 = mergeArgs { foo = "left"; } { bar = "right"; };
+  r11 = mergeArgs { foo = "left"; } { foo = "right"; };
+in
+
+assert assertEq "buildInputs merges both sides" r1.buildInputs [
+  1
+  2
+];
+assert assertEq "nativeBuildInputs merges both sides" r2.nativeBuildInputs [
+  1
+  2
+];
+assert assertEq "packages merges both sides" r3.packages [
+  1
+  2
+];
+assert assertEq "env merges both sides" r4.env {
+  A = "1";
+  B = "2";
+};
+assert assertEq "env right overrides left" r5.env { A = "2"; };
+assert assertEq "buildInputs left missing" r6.buildInputs [ 1 ];
+assert assertEq "buildInputs right missing" r7.buildInputs [ 1 ];
+assert assertEq "env left missing" r8.env { A = "1"; };
+assert assertEq "env right missing" r9.env { A = "1"; };
+assert assertEq "plain attrs from both sides" r10.foo "left";
+assert assertEq "plain attrs from both sides (bar)" r10.bar "right";
+assert assertEq "plain attrs right overrides left" r11.foo "right";
+
+pkgs.runCommand "mergeArgs-tests" { } "touch $out"
diff --git a/checks/nextest/Cargo.lock b/checks/nextest/Cargo.lock
new file mode 100644
index 0000000..2418b72
--- /dev/null
+++ b/checks/nextest/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "nextest-check"
+version = "0.1.0"
diff --git a/checks/nextest/Cargo.toml b/checks/nextest/Cargo.toml
new file mode 100644
index 0000000..9699c6b
--- /dev/null
+++ b/checks/nextest/Cargo.toml
@@ -0,0 +1,12 @@
+[workspace]
+members = ["crate"]
+resolver = "2"
+
+[workspace.package]
+edition = "2021"
+
+[profile.ci]
+debug = "line-tables-only"
+inherits = "dev"
+incremental = false
+lto = "off"
diff --git a/checks/nextest/crate/Cargo.toml b/checks/nextest/crate/Cargo.toml
new file mode 100644
index 0000000..0919c58
--- /dev/null
+++ b/checks/nextest/crate/Cargo.toml
@@ -0,0 +1,4 @@
+[package]
+name = "nextest-check"
+version = "0.1.0"
+edition = { workspace = true }
diff --git a/checks/nextest/crate/src/lib.rs b/checks/nextest/crate/src/lib.rs
new file mode 100644
index 0000000..2837a57
--- /dev/null
+++ b/checks/nextest/crate/src/lib.rs
@@ -0,0 +1,4 @@
+#[test]
+fn it_works() {
+    assert_eq!(2 + 2, 4);
+}
diff --git a/checks/nextest/default.nix b/checks/nextest/default.nix
new file mode 100644
index 0000000..2a0772a
--- /dev/null
+++ b/checks/nextest/default.nix
@@ -0,0 +1,38 @@
+{ pkgs, flakeboxLib }:
+let
+  rootDir = builtins.path {
+    name = "nextest";
+    path = ./.;
+  };
+
+  buildPaths = [
+    "Cargo.toml"
+    "Cargo.lock"
+    "crate"
+  ];
+
+  multiOutput = (flakeboxLib.craneMultiBuild { }) (
+    craneLib':
+    let
+      src = flakeboxLib.filterSubPaths {
+        root = rootDir;
+        paths = buildPaths;
+      };
+
+      craneLib = craneLib'.overrideArgs {
+        pname = "nextest-check";
+        version = "0.0.1";
+        inherit src;
+      };
+    in
+    {
+      workspaceDeps = craneLib.buildWorkspaceDepsOnly { };
+      nextest = craneLib.cargoNextest {
+        cargoArtifacts = craneLib.buildWorkspaceDepsOnly { };
+      };
+    }
+  );
+in
+pkgs.linkFarmFromDrvs "nextest" [
+  multiOutput.ci.nextest
+]
diff --git a/docs/building-new-project.md b/docs/building-new-project.md
index 9d6c5fa..0eccba6 100644
--- a/docs/building-new-project.md
+++ b/docs/building-new-project.md
@@ -145,7 +145,8 @@ index 615d404..860927a 100644
 +  outputs = { self, nixpkgs, flakebox, flake-utils }:
 +    flake-utils.lib.eachDefaultSystem (system:
 +      let
-+        flakeboxLib = flakebox.lib.${system} { };
++        pkgs = nixpkgs.legacyPackages.${system};
++        flakeboxLib = flakebox.lib.mkLib pkgs { };
 +      in
 +      {
 +        devShells = flakeboxLib.mkShells {
@@ -179,7 +180,8 @@ Since that's a bit handful, let me paste the whole content:
   outputs = { self, nixpkgs, flakebox, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
       let
-        flakeboxLib = flakebox.lib.${system} { };
+        pkgs = nixpkgs.legacyPackages.${system};
+        flakeboxLib = flakebox.lib.mkLib pkgs { };
       in
       {
         devShells = flakeboxLib.mkShells {
@@ -316,7 +318,8 @@ index cb41316..08c8f65 100644
 @@ -16,8 +16,38 @@
      flake-utils.lib.eachDefaultSystem (system:
        let
-         flakeboxLib = flakebox.lib.${system} { };
++        pkgs = nixpkgs.legacyPackages.${system};
+         flakeboxLib = flakebox.lib.mkLib pkgs { };
 +
 +        rustSrc = flakeboxLib.filterSubPaths {
 +          root = builtins.path {
@@ -407,19 +410,24 @@ Skipping semgrep check: .config/semgrep.yaml empty
 Let's discuss each part of the code:
 
 ```
-        flakeboxLib = flakebox.lib.${system} { };
+        pkgs = nixpkgs.legacyPackages.${system};
+        flakeboxLib = flakebox.lib.mkLib pkgs { };
 ```
 
 `let ... in <expr>` in Nix is used to bind values
 to names, that can later be used in `<expr>` following
 in.
 
-Our first name binding is `flakeboxLib` which exposes all
+Our first name binding is `pkgs` which is the standard way to
+get the nixpkgs package set for the current `system`.
+
+Next is `flakeboxLib` which exposes all
 Flakebox APIs. `flakebox` is the name of the input
-defined in the flake, `flakebox.lib.${system}` is
-the library output it exposes for the current `system`.
-`flakebox.lib.${system} { }` is a function call, where
-`{ }` are the arguments (empty set, defaults).
+defined in the flake, `flakebox.lib.mkLib` is
+the function used to initialize the library.
+`flakebox.lib.mkLib pkgs { }` is a function call, where
+`pkgs` is the nixpkgs package set and `{ }` are the
+configuration arguments (empty set, defaults).
 
 This is where you can enable/disable/configure various features of flakebox. A list of config options can be found [here](./nixos-options.md)
 
@@ -714,11 +722,9 @@ index a65ba7a..f4c64d7 100644
      flake-utils.lib.eachDefaultSystem (system:
        let
 +
-+        pkgs = import nixpkgs {
-+          inherit system;
-+        };
++        pkgs = nixpkgs.legacyPackages.${system};
 +
-         flakeboxLib = flakebox.lib.${system} { };
+         flakeboxLib = flakebox.lib.mkLib pkgs { };
  
          rustSrc = flakeboxLib.filterSubPaths {
 @@ -36,6 +41,10 @@
diff --git a/docs/getting-started.md b/docs/getting-started.md
index 39211a8..5783b89 100644
--- a/docs/getting-started.md
+++ b/docs/getting-started.md
@@ -48,8 +48,10 @@ Following modifications to `flake.nix` are needed:
         # Set project name
         projectName = "my-project";
 
+        pkgs = nixpkgs.legacyPackages.${system};
+
         # Set up the flakebox lib for your system
-        flakeboxLib = flakebox.lib.${system} {
+        flakeboxLib = flakebox.lib.mkLib pkgs {
           # customizations go here
           config = {
             typos.pre-commit.enable = false;
diff --git a/docs/native-toolchains.md b/docs/native-toolchains.md
index c77ad97..cb2ab2d 100644
--- a/docs/native-toolchains.md
+++ b/docs/native-toolchains.md
@@ -11,7 +11,7 @@ These toolchains are meant to be native target toolchains.
 To change the default toolchain channel to nightly use:
 
 ```nix
-flakeboxLib = flakebox.lib.${system} {
+flakeboxLib = flakebox.lib.mkLib pkgs {
   config = {
     toolchain.channel = "complete"; # or "latest", see https://github.com/nix-community/fenix for details
   };
diff --git a/flake.lock b/flake.lock
index efdc4b6..d8e51a6 100644
--- a/flake.lock
+++ b/flake.lock
@@ -25,31 +25,16 @@
     },
     "crane": {
       "locked": {
-        "lastModified": 1758758545,
-        "narHash": "sha256-NU5WaEdfwF6i8faJ2Yh+jcK9vVFrofLcwlD/mP65JrI=",
+        "lastModified": 1771121070,
+        "narHash": "sha256-aIlv7FRXF9q70DNJPI237dEDAznSKaXmL5lfK/Id/bI=",
         "owner": "ipetkov",
         "repo": "crane",
-        "rev": "95d528a5f54eaba0d12102249ce42f4d01f4e364",
-        "type": "github"
-      },
-      "original": {
-        "owner": "ipetkov",
-        "ref": "v0.21.1",
-        "repo": "crane",
-        "type": "github"
-      }
-    },
-    "crane_2": {
-      "locked": {
-        "lastModified": 1755993354,
-        "narHash": "sha256-FCRRAzSaL/+umLIm3RU3O/+fJ2ssaPHseI2SSFL8yZU=",
-        "owner": "ipetkov",
-        "repo": "crane",
-        "rev": "25bd41b24426c7734278c2ff02e53258851db914",
+        "rev": "a2812c19f1ed2e5ed5ce2ef7109798b575c180e1",
         "type": "github"
       },
       "original": {
         "owner": "ipetkov",
+        "ref": "v0.23.1",
         "repo": "crane",
         "type": "github"
       }
@@ -83,11 +68,11 @@
         "rust-analyzer-src": "rust-analyzer-src"
       },
       "locked": {
-        "lastModified": 1767941162,
-        "narHash": "sha256-7qJDycrXto4xrQWHbj5BkrRWt/hcfZtjlCstEJTyfJ8=",
+        "lastModified": 1771743970,
+        "narHash": "sha256-eri4eY0fUouYxBgWxJAJzG+xTGXVI7VeNJGcJrqpEt0=",
         "owner": "nix-community",
         "repo": "fenix",
-        "rev": "80b1a19a713e2558c411f3259fecb1edd4b5b327",
+        "rev": "2af8ae8bbe91833a54bd3b9cc24c326b66972a8e",
         "type": "github"
       },
       "original": {
@@ -136,11 +121,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1767799921,
-        "narHash": "sha256-r4GVX+FToWVE2My8VVZH4V0pTIpnu2ZE8/Z4uxGEMBE=",
+        "lastModified": 1771714954,
+        "narHash": "sha256-nhZJPnBavtu40/L2aqpljrfUNb2rxmWTmSjK2c9UKds=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "d351d0653aeb7877273920cd3e823994e7579b0b",
+        "rev": "afbbf774e2087c3d734266c22f96fca2e78d3620",
         "type": "github"
       },
       "original": {
@@ -157,18 +142,17 @@
         "fenix": "fenix",
         "flake-utils": "flake-utils_2",
         "nixpkgs": "nixpkgs",
-        "systems": "systems_2",
-        "wild": "wild"
+        "systems": "systems_2"
       }
     },
     "rust-analyzer-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1767905519,
-        "narHash": "sha256-mRU9VEhGQE9dnOU3pu1Rx3dZO4NpZO+cnC0rPMFcCqE=",
+        "lastModified": 1771639390,
+        "narHash": "sha256-igbphgls7JmrblWCIbgBGcL/ZWj0Iv+InySvuhLC5Ew=",
         "owner": "rust-lang",
         "repo": "rust-analyzer",
-        "rev": "ff9a2e88b14907562294838f83963e5966f717de",
+        "rev": "af68fc6e782f218c262a8e7e5718ce7276f697a2",
         "type": "github"
       },
       "original": {
@@ -207,28 +191,6 @@
         "repo": "default",
         "type": "github"
       }
-    },
-    "wild": {
-      "inputs": {
-        "crane": "crane_2",
-        "nixpkgs": [
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1762215977,
-        "narHash": "sha256-x0IZuWjj0LRMj4pu2FVaD8SENm/UVtE1e4rl0EOZZZM=",
-        "owner": "davidlattimore",
-        "repo": "wild",
-        "rev": "7daaf0c89f7b4b9c9ded36e7b3c72aa6512537a1",
-        "type": "github"
-      },
-      "original": {
-        "owner": "davidlattimore",
-        "ref": "0.7.0",
-        "repo": "wild",
-        "type": "github"
-      }
     }
   },
   "root": "root",
diff --git a/flake.nix b/flake.nix
index ebdcbb7..e338e54 100644
--- a/flake.nix
+++ b/flake.nix
@@ -9,7 +9,7 @@
     flake-utils.inputs.systems.follows = "systems";
 
     crane = {
-      url = "github:ipetkov/crane/v0.21.1";
+      url = "github:ipetkov/crane/v0.23.1";
     };
 
     fenix = {
@@ -17,11 +17,6 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
 
-    wild = {
-      url = "github:davidlattimore/wild/0.7.0";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
-
     android-nixpkgs = {
       url = "github:tadfisher/android-nixpkgs?rev=d3cbdd2a82b3d054b4e283d28ba27548186a88e7"; # stable channel https://github.com/tadfisher/android-nixpkgs/tree/stable
       inputs.nixpkgs.follows = "nixpkgs";
@@ -64,7 +59,7 @@
     // flake-utils.lib.eachDefaultSystem (
       system:
       let
-        pkgs = nixpkgs.legacyPackages.${system}.extend (import inputs.wild);
+        pkgs = nixpkgs.legacyPackages.${system};
 
         flakeboxLib = mkLib pkgs {
           config = {
diff --git a/lib/modules/github.nix b/lib/modules/github.nix
index 5856c4e..779be3a 100644
--- a/lib/modules/github.nix
+++ b/lib/modules/github.nix
@@ -196,7 +196,7 @@ in
                     uses = "actions/cache@v3";
                     "with" = {
                       path = "~/.cargo";
-                      key = ''''${{ runner.os }}-''${{ hashFiles('Cargo.lock') }}'';
+                      key = "\${{ runner.os }}-\${{ hashFiles('Cargo.lock') }}";
                     };
                   }