diff --git a/shell.nix b/shell.nix
index a415d7907..7f456b00e 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,3 +1,4 @@
+# TODO(tom): Use system nixpkgs exclusively once 1.18 is in a stable release.
 # This is a shell.nix file used to describe the environment that tailscale needs
 # for development. This includes a lot of the basic tools that you need in order
 # to get started. We hope this file will be useful for users of Nix on macOS or
@@ -9,16 +10,42 @@
 # Also look into direnv: https://direnv.net/, this can make it so that you can
 # automatically get your environment set up when you change folders into the
 # project.
-{ pkgs ? import <nixpkgs> {} }:
 
-pkgs.mkShell {
-  # This specifies the tools that are needed for people to get started with
-  # development. These tools include:
-  #  - The Go compiler toolchain (and all additional tooling with it)
-  #  - gotools for goimports, a robust formatting tool for Go source code
-  #  - gopls, the language server for Go to increase editor integration
-  #  - git, the version control program (used in some scripts)
-  buildInputs = with pkgs; [
-    go gotools gopls git
-  ];
-}
+{
+	pkgs ? import <nixpkgs> {},
+	nixosUnstable ? import (fetchTarball https://github.com/NixOS/nixpkgs/archive/refs/heads/nixpkgs-unstable.tar.gz) { },
+	tailscale-go-rev ? "5ce3ec4d89c72f2a2b6f6f5089c950d7a6a33530",
+	tailscale-go-sha ? "sha256-KMOfzmikh30vEkViEkWUsOHczUifSTiRL6rhKQpHCRI=",
+}:
+let
+	tailscale-go = pkgs.lib.overrideDerivation nixosUnstable.go_1_18 (attrs: rec {
+		name = "tailscale-go-${version}";
+		version = tailscale-go-rev;
+		src = pkgs.fetchFromGitHub {
+		  owner = "tailscale";
+		  repo = "go";
+		  rev = tailscale-go-rev;
+		  sha256 = tailscale-go-sha;
+		};
+		nativeBuildInputs = attrs.nativeBuildInputs ++ [ pkgs.git ];
+		# Remove dependency on xcbuild as that causes iOS/macOS builds to fail.
+		propagatedBuildInputs = [];
+		checkPhase = "";
+		# Our forked tailscale reads this env var to embed the git hash
+		# into the Go build version.
+		TAILSCALE_TOOLCHAIN_REV = tailscale-go-rev;
+	});
+in
+	pkgs.mkShell {
+	  # This specifies the tools that are needed for people to get started with
+	  # development. These tools include:
+	  #  - The Go compiler toolchain (and all additional tooling with it)
+	  #  - gotools for goimports, a robust formatting tool for Go source code
+	  #  - gopls, the language server for Go to increase editor integration
+	  #  - git, the version control program (used in some scripts)
+	  buildInputs = [
+	    pkgs.git
+	    nixosUnstable.gotools nixosUnstable.gopls
+	    tailscale-go
+	  ];
+	}