diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..616180c
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,64 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": [
+          "systems"
+        ]
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1747426396,
+        "narHash": "sha256-826f9fjpBgY4drKlk37PW9bQC95uFKFNfAOUjNSadUw=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "05103c54f28fafc230f3a5b95d9d626143bf5933",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "release-24.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "systems": "systems"
+      }
+    },
+    "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/flake.nix b/flake.nix
new file mode 100644
index 0000000..eb1997d
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,30 @@
+{
+  description = "flake for rp2040 dev";
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/release-24.11";
+    systems.url = "github:nix-systems/default";
+    flake-utils = {
+      url = "github:numtide/flake-utils";
+      inputs.systems.follows = "systems";
+    };
+  };
+
+  outputs =
+    { nixpkgs, flake-utils, ... }@inputs:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        openocd = pkgs.callPackage ./openocd.nix { };
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = with pkgs; [
+            openocd
+          ];
+        };
+        default = openocd;
+      }
+    );
+}
+
diff --git a/openocd.nix b/openocd.nix
new file mode 100644
index 0000000..5ffab31
--- /dev/null
+++ b/openocd.nix
@@ -0,0 +1,106 @@
+{
+  stdenv,
+  lib,
+  fetchFromGitHub,
+  pkg-config,
+  libtool,
+  autoconf,
+  automake,
+  tcl,
+}:
+let
+
+  isWindows = stdenv.hostPlatform.isWindows;
+  notWindows = !isWindows;
+
+in
+stdenv.mkDerivation rec {
+  pname = "openocd-pico";
+  version = "sdk-2.0.0";
+  src = fetchFromGitHub {
+          owner = "raspberrypi";
+          repo = "openocd";
+          rev = "cf9c0b41cd5c45b2faf01b4fd1186f160342b7b7";
+          hash = "sha256-8PpBT+RRd8FiVBhzfsTRcIrzwrd1Y4zNYEfDga+11qU=";
+          leaveDotGit = true;
+          fetchSubmodules = true;
+  };
+
+  nativeBuildInputs = [
+    pkg-config
+    libtool
+    tcl
+    autoconf
+    automake
+  ];
+
+  # This emulates the bootstrap script, but is ran as a hook so it can use
+  # the native build inputs.
+  preConfigure = ''
+    # SPDX-License-Identifier: GPL-2.0-or-later
+
+    # Run the autotools bootstrap sequence to create the configure script
+
+    # Abort execution on error
+    set -e
+
+    # bootstrap the autotools
+    (
+    set -x
+    aclocal --warnings=all
+    # Apparently, not all versions of libtoolize support option --warnings=all .
+    libtoolize --automake --copy
+    autoconf --warnings=all
+    autoheader --warnings=all
+    automake --warnings=all --gnu --add-missing --copy
+    )
+
+    if [ -x src/jtag/drivers/libjaylink/autogen.sh ]; then
+        (
+        cd src/jtag/drivers/libjaylink
+        ./autogen.sh
+        )
+    fi
+
+    echo "Bootstrap complete. Quick build instructions:"
+    echo "./configure ...."
+  '';
+
+
+  configureFlags = [
+    "--disable-werror"
+  ];
+
+  enableParallelBuilding = true;
+
+  postInstall = lib.optionalString stdenv.hostPlatform.isLinux ''
+    mkdir -p "$out/etc/udev/rules.d"
+    rules="$out/share/openocd/contrib/60-openocd.rules"
+    if [ ! -f "$rules" ]; then
+        echo "$rules is missing, must update the Nix file."
+        exit 1
+    fi
+    ln -s "$rules" "$out/etc/udev/rules.d/"
+  '';
+
+  meta = with lib; {
+    description = "Free and Open On-Chip Debugging, In-System Programming and Boundary-Scan Testing";
+    mainProgram = "openocd";
+    longDescription = ''
+      OpenOCD provides on-chip programming and debugging support with a layered
+      architecture of JTAG interface and TAP support, debug target support
+      (e.g. ARM, MIPS), and flash chip drivers (e.g. CFI, NAND, etc.).  Several
+      network interfaces are available for interactiving with OpenOCD: HTTP,
+      telnet, TCL, and GDB.  The GDB server enables OpenOCD to function as a
+      "remote target" for source-level debugging of embedded systems using the
+      GNU GDB program.
+    '';
+    homepage = "https://openocd.sourceforge.net/";
+    license = licenses.gpl2Plus;
+    maintainers = with maintainers; [
+      bjornfor
+      prusnak
+    ];
+    platforms = platforms.unix ++ platforms.windows;
+  };
+}