9 files changed, 33 insertions, 128 deletions
diff --git a/flake.lock b/flake.lock
index d81a2dc4..bac9eb78 100644
--- a/flake.lock
+++ b/flake.lock
@@ -362,6 +362,22 @@
         "type": "github"
       }
     },
+    "library": {
+      "locked": {
+        "lastModified": 1734626644,
+        "narHash": "sha256-p/RVC4Rp5AGN3qwlVoQJHkbEkvcilSr2lWfRgnlRXlQ=",
+        "ref": "prime",
+        "rev": "1021c1ffe1dd8dd75380dac618b93ff2cefd81f4",
+        "revCount": 1,
+        "type": "git",
+        "url": "https://git.vhack.eu/vhack.eu/nix-library"
+      },
+      "original": {
+        "ref": "prime",
+        "type": "git",
+        "url": "https://git.vhack.eu/vhack.eu/nix-library"
+      }
+    },
     "nix-darwin": {
       "inputs": {
         "nixpkgs": [
@@ -733,6 +749,7 @@
         "home-manager": "home-manager",
         "impermanence": "impermanence",
         "lanzaboote": "lanzaboote",
+        "library": "library",
         "nix-darwin": "nix-darwin",
         "nix-index-database": "nix-index-database",
         "nixVim": "nixVim",
diff --git a/flake.nix b/flake.nix
index 80f8bc35..b748e0aa 100644
--- a/flake.nix
+++ b/flake.nix
@@ -14,6 +14,10 @@
     nixpkgs-tfc.url = "github:soispha/nixpkgs/add-termfilechooser";
     nixpkgs-onlykey.url = "github:soispha/nixpkgs/fix-onlykey-agent";
 
+    library = {
+      url = "git+https://git.vhack.eu/vhack.eu/nix-library?ref=prime";
+    };
+
     # inputs for following
     nix-darwin = {
       url = "github:lnl7/nix-darwin";
@@ -192,6 +196,7 @@
       };
     };
     lanzaboote = {
+      # TODO: Subscribe to their update feed. <2024-12-18>
       url = "github:nix-community/lanzaboote/v0.4.1";
       inputs = {
         nixpkgs.follows = "nixpkgs-stable";
@@ -262,6 +267,7 @@
     nixpkgs-stable,
     nixpkgs-tfc,
     nixpkgs-onlykey,
+    library,
     # modules
     home-manager,
     nixos-generators,
@@ -285,7 +291,7 @@
     system = "x86_64-linux";
     sysLib = shell_library.lib.${system};
 
-    nixLib = import ./lib {};
+    inherit (library) nixLib;
 
     pkgsStable = nixpkgs-stable.legacyPackages.${system};
     pkgs = nixpkgs.legacyPackages.${system};
diff --git a/flake/default.nix b/flake/default.nix
index 16ae52c6..2c8d6f6b 100644
--- a/flake/default.nix
+++ b/flake/default.nix
@@ -41,6 +41,7 @@
       # my things
       shell_library
       sysLib
+      nixLib
       templates
       # modules
       home-manager
@@ -61,7 +62,7 @@
   };
 
   tests = import ../tests {
-    inherit pkgs nixpkgs_as_input myPkgs sysLib;
+    inherit pkgs nixpkgs_as_input myPkgs sysLib nixLib;
     inherit (pkgs) lib;
     extraModules = {
       termfilechooser = "${nixpkgs_open_prs.nixpkgs-tfc}/nixos/modules/config/xdg/portals/termfilechooser.nix";
@@ -80,7 +81,7 @@
 in {
   inherit nixosConfigurations;
   checks."${system}" =
-    nixLib.maybeMerge {
+    nixLib.warnMerge {
       inherit
         (self.packages."${system}")
         nvim
diff --git a/flake/nixosConfigurations/default.nix b/flake/nixosConfigurations/default.nix
index d51e57a5..7d98f868 100644
--- a/flake/nixosConfigurations/default.nix
+++ b/flake/nixosConfigurations/default.nix
@@ -8,6 +8,7 @@
   # my things
   shell_library,
   sysLib,
+  nixLib,
   templates,
   # modules
   home-manager,
@@ -47,6 +48,7 @@
       myPkgs
       shell_library
       sysLib
+      nixLib
       # extra information
       system
       # modules
diff --git a/lib/by-name-overlay.nix b/lib/by-name-overlay.nix
deleted file mode 100644
index 4d700a8f..00000000
--- a/lib/by-name-overlay.nix
+++ /dev/null
@@ -1,76 +0,0 @@
-{warn}:
-# Adapted from this: https://github.com/NixOS/nixpkgs/blob/1814b56453c91192f6d5a6276079948f9fe96c18/pkgs/top-level/by-name-overlay.nix
-# This file should not depend on `pkgs` and thus not use `lib`.
-{
-  baseDirectory,
-  fileName,
-  finalizeFunction,
-  coImportsNameFunction ? null,
-  coImportsWarnMessageObject ? null,
-}: let
-  # Takes a list of attrs as input and returns one merged attr set.
-  flattenAttrs = list:
-    if builtins.isList list
-    then
-      builtins.foldl' (acc: elem:
-        if builtins.isList elem
-        # Merging them with `//` is okay here, as we can be sure that the attr names are
-        # unique (they were separate dictionary after all)
-        then acc // (flattenAttrs elem)
-        else acc // elem) {}
-      list
-    else list;
-
-  # From nixpkgs/lib {{{
-  # These functions are taken straight out of the `nixpkgs/lib`.
-  # We can't depended on `pkgs` (and thus on `lib`), because the `pkgs` module argument
-  # is only defined in the `nixpkgs` module (which is imported through this function).
-  mapAttrsToList = f: attrs:
-    builtins.map (name: f name attrs.${name}) (builtins.attrNames attrs);
-
-  nameValuePair = name: value: {inherit name value;};
-  filterAttrs = pred: set:
-    builtins.listToAttrs (builtins.concatMap (name: let
-      v = set.${name};
-    in
-      if pred name v
-      then [(nameValuePair name v)]
-      else []) (builtins.attrNames set));
-  # }}}
-
-  # Module files for a single shard
-  # Type: String -> String -> ListOf Path
-  namesForShard = shard: type:
-    if type != "directory"
-    then warn "Ignored non-directory, whilst importing by-name directory (${fileName}): '${shard}'" {}
-    else let
-      mkPath = name: _type: let
-        path = baseDirectory + "/${shard}/${name}" + "/${fileName}";
-        coImportPath =
-          if coImportsNameFunction != null
-          then
-            coImportsNameFunction
-            {inherit shard name;}
-          else path;
-      in
-        if builtins.pathExists path
-        then
-          if builtins.pathExists coImportPath
-          then path
-          else warn "'${builtins.toString coImportPath}' does not exist. Should include ${coImportsWarnMessageObject} for '${shard}/${name}'" path
-        else warn "'${builtins.toString path}' does not exist. Skipped" null;
-    in
-      filterAttrs (name: value: value != null)
-      (builtins.mapAttrs
-        mkPath
-        (builtins.readDir (baseDirectory + "/${shard}")));
-
-  # A list of all module paths.
-  # These can the be simply injected into `import`
-  files = flattenAttrs (mapAttrsToList namesForShard (builtins.readDir baseDirectory));
-  output =
-    builtins.mapAttrs
-    finalizeFunction
-    files;
-in
-  output
diff --git a/lib/default.nix b/lib/default.nix
deleted file mode 100644
index dfa9fb17..00000000
--- a/lib/default.nix
+++ /dev/null
@@ -1,42 +0,0 @@
-{}: let
-  # string -> string -> string
-  colorize = color: string: "[${color}m${string}[0m";
-
-  # Taken from `nixpkgs/lib`.
-  # Is here to avoid a dependency on `lib` (making this file easy to test with `nix eval`)
-  warn =
-    # Since Nix 2.23, https://github.com/NixOS/nix/pull/10592
-    builtins.warn
-    or (
-      # Do not eta reduce v, so that we have the same strictness as `builtins.warn`.
-      msg: v:
-      # `builtins.warn` requires a string message, so we enforce that in our implementation, so that callers aren't accidentally incompatible with newer Nix versions.
-        assert builtins.isString msg;
-          builtins.trace "${colorize "1;35" "evaluation warning:"} ${msg}" v
-    );
-in {
-  mkByName = import ./by-name-overlay.nix {inherit warn;};
-
-  # Only merge two attrsets if the RHS does not share names with the LHS.
-  # # Example:
-  # ```nix
-  # let
-  # attr1 = {atuin = "first"; default = "second";};
-  # attr2 = {atuin = "hi"; other = "hi2";};
-  # in
-  # maybeMerge attr1 attr2 "Failed to merge"
-  # ```
-  # # Type:
-  # {} -> {} -> string -> {}
-  maybeMerge = lhs: rhs: sourceSet: let
-    overridden = builtins.intersectAttrs lhs rhs;
-    merged = lhs // rhs;
-    mkWarning = overriddenAttrs:
-      builtins.concatStringsSep " " (builtins.map (colorize "1;97") (builtins.attrNames overriddenAttrs));
-  in
-    if overridden != {}
-    then
-      warn "Attributes overridden while merging ${sourceSet}: ${mkWarning overridden}"
-      merged
-    else merged;
-}
diff --git a/modules/default.nix b/modules/default.nix
index 17780e63..1df511a1 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -1,8 +1,6 @@
 # NOTE: This file **must** not depend on `pkgs`. This is because `pkgs` is defined in a
 # module imported by it, and thus would require infinite recursion.  <2024-10-18>
-{...}: let
-  nixLib = import ../lib {};
-
+{nixLib, ...}: let
   files =
     builtins.attrValues
     (nixLib.mkByName {
diff --git a/pkgs/default.nix b/pkgs/default.nix
index 3ed326ac..1f0a25cc 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -9,8 +9,8 @@
   mMM = maybeMergeMessage;
   callPackage =
     lib.callPackageWith
-    (nixLib.maybeMerge
-      (nixLib.maybeMerge
+    (nixLib.warnMerge
+      (nixLib.warnMerge
         pkgs
         myPkgs
         mMM)
diff --git a/tests/default.nix b/tests/default.nix
index 24b6fa65..c36a5906 100644
--- a/tests/default.nix
+++ b/tests/default.nix
@@ -1,13 +1,12 @@
 {
   lib,
+  nixLib,
   pkgs,
   myPkgs,
   nixpkgs_as_input,
   sysLib,
   extraModules,
 }: let
-  nixLib = import ../lib {};
-
   mkTest = import ./infrastructure {
     inherit
       pkgs