diff --git a/nix/pkgs.nix b/nix/pkgs.nix
index bcb2cd4..24042f3 100644
--- a/nix/pkgs.nix
+++ b/nix/pkgs.nix
@@ -11,5 +11,5 @@ let
   };
 in
 {
-  inherit pkgs hp;
+  inherit pkgs hp sources;
 }
diff --git a/nix/toc.nix b/nix/toc.nix
index 22b9cef..541a06f 100644
--- a/nix/toc.nix
+++ b/nix/toc.nix
@@ -4,26 +4,54 @@
 
 let
   packages = import ./pkgs.nix { inherit compiler; };
-  inherit (packages) pkgs;
+  inherit (packages) pkgs sources;
 
-  toc = pkgs.stdenv.mkDerivation {
-    name = "gh-md-toc-24-05-2020";
+  toc = pkgs.resholve.mkDerivation {
+    pname = "gh-md-toc";
+    version = sources.github-markdown-toc.version;
 
-    src = builtins.fetchurl {
-      url = "https://raw.githubusercontent.com/ekalinin/github-markdown-toc/488f310064b16c1eb9c17862cc5844189ee65955/gh-md-toc";
-      sha256 = "1253n0qw3xgikl7gcdicg3vmc3wzz6122bmhmffj1irrachq89fi";
-    };
+    src = sources.github-markdown-toc;
 
-    phases = [
-      "installPhase"
-      "patchPhase"
-    ];
+    dontConfigure = true;
+    dontBuild = true;
 
     installPhase = ''
-      mkdir -p $out/bin
-      cp $src $out/bin/gh-md-toc
-      chmod +x $out/bin/gh-md-toc
+      runHook preInstall
+
+      mkdir -p "$out/bin"
+      cp gh-md-toc "$out/bin/gh-md-toc"
+      chmod +x "$out/bin/gh-md-toc"
+
+      runHook postInstall
     '';
+
+    solutions = {
+      default = {
+        scripts = [ "bin/gh-md-toc" ];
+        interpreter = "${pkgs.bash}/bin/bash";
+        inputs = [
+          pkgs.bash
+          pkgs.coreutils
+          pkgs.curl
+          pkgs.gawk
+          pkgs.gnugrep
+          pkgs.gnused
+          # which
+        ];
+        fix = {
+          "$grepcmd" = [ "grep" "-Eo" ];
+          "$SHELL" = [ "bash" ];
+        };
+        keep = {
+          "$tool" = true;
+        };
+        fake = {
+          external = [
+            "wget"
+          ];
+        };
+      };
+    };
   };
 in
 pkgs.writeShellScriptBin "update-toc" ''
diff --git a/npins/sources.json b/npins/sources.json
index b299682..a274f5b 100644
--- a/npins/sources.json
+++ b/npins/sources.json
@@ -1,5 +1,20 @@
 {
   "pins": {
+    "github-markdown-toc": {
+      "type": "GitRelease",
+      "repository": {
+        "type": "GitHub",
+        "owner": "ekalinin",
+        "repo": "github-markdown-toc"
+      },
+      "pre_releases": false,
+      "version_upper_bound": null,
+      "release_prefix": null,
+      "version": "0.10.0",
+      "revision": "7d0a86b3be2e8e959cd9747fcf2c4a1f0e6a24eb",
+      "url": "https://api.github.com/repos/ekalinin/github-markdown-toc/tarball/0.10.0",
+      "hash": "14gnj1pwbscs0bj1wkzc342r0v1d5ib4c8bizyqg5djkl4j3rlzh"
+    },
     "nixpkgs": {
       "type": "Channel",
       "name": "nixos-unstable",