feat: Recursion bindings

.envrc

@@ -0,0 +1,20 @@
+# Based on https://github.com/direnv/direnv-vscode/blob/158e8302c2594cc0eaa5f8b4f0cafedd4e1c0315/.envrc
+
+# You can define your system-specific logic (like Git settings or GH tokens) in .envrc.local
+# If that logic is usable by other people and might improve development environment, consider
+# contributing it to this file!
+
+source_env_if_exists .envrc.local
+
+if [[ -z "${SKIP_NIX:-}" ]] && has nix; then
+
+	if nix flake metadata &>/dev/null && has use_flake; then
+		# use flakes if possible
+		use flake
+
+	else
+		# Otherwise fall back to pure nix
+		use nix
+	fi
+
+fi

.gitignore

@@ -5,5 +5,7 @@
 # These are backup files generated by rustfmt
 **/*.rs.bk
 
-# Generated by nix
+# Nix stuff
 result
+.envrc.local
+.direnv

.vscode/extensions.json

@@ -0,0 +1,13 @@
+{
+	// See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+	// Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
+	// List of extensions which should be recommended for users of this workspace.
+	"recommendations": [
+		"mkhl.direnv",
+		"jnoortheen.nix-ide",
+		"rust-lang.rust-analyzer",
+		"redhat.vscode-yaml"
+	],
+	// List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+	"unwantedRecommendations": []
+}

.vscode/settings.json

@@ -0,0 +1,16 @@
+{
+    "direnv.restart.automatic": true,
+    "redhat.telemetry.enabled": false,
+    "yaml.recommendations.show": false,
+    "nix.serverPath": "nil",
+    "nix.enableLanguageServer": true,
+    "nix.serverSettings": {
+        "nil": {
+            "formatting": {
+                "command": [
+                    "nixpkgs-fmt"
+                ]
+            }
+        }
+    },
+}

README.md

@@ -40,6 +40,80 @@ pub fn pedersen() {
 }
 ```
 
-## Nix
+## Working on this project
 
-We provide a [Nix Flake](./flake.nix) that shows you how to configure an environment if you're building your Rust code inside Nix.
+Due to the large number of native dependencies, this project uses [Nix](https://nixos.org/) and [direnv](https://direnv.net/) to streamline the development experience.
+
+### Setting up your environment
+
+For the best experience, please follow these instructions to setup your environment:
+1. Install Nix following [their guide](https://nixos.org/download.html) for your operating system
+2. Create the file `~/.config/nix/nix.conf` with the contents:
+```ini
+experimental-features = nix-command
+extra-experimental-features = flakes
+```
+3. Install direnv into your Nix profile by running:
+```sh
+nix profile install nixpkgs#direnv
+```
+4. Add direnv to your shell following [their guide](https://direnv.net/docs/hook.html)
+5. Restart your shell
+
+### Shell & editor experience
+
+Now that your environment is set up, you can get to work on the project.
+
+1. Clone the repository, such as:
+```sh
+git clone git@github.com:noir-lang/barretenberg-sys
+```
+2. Navigate to the directory:
+```sh
+cd barretenberg-sys
+```
+3. You should see a __direnv error__ because projects aren't allowed by default. Make sure you trust our `.envrc` file, then you need to run:
+```sh
+direnv allow
+```
+4. Now, wait awhile for all the native dependencies to be built. This will take some time and direnv will warn you that it is taking a long time, but we just need to let it run.
+5. Once you are presented with your prompt again, you can start your editor within the project directory (we recommend [VSCode](https://code.visualstudio.com/)):
+```sh
+code .
+```
+6. (Recommended) When launching VSCode for the first time, you should be prompted to install our recommended plugins. We highly recommend installing these for the best development experience.
+
+### Building and testing
+
+Building and testing the project is done through Nix commands.
+
+To build the project, run `nix build .` (or `nix build . -L` for verbose output).
+
+To run clippy and all tests in the project, run `nix flake check` (or `nix flake check -L` for verbose output).
+
+### Building against a different local/remote version of Barretenberg
+
+If you are working on this crate, it is likely that you want to incorporate changes from some other version of Barretenberg
+instead of the version this project is pinned against.
+
+To reference a different version of Barretenberg, you can add the `--override-input` flag. For example:
+
+```sh
+nix build . --override-input barretenberg /home/phated/barretenberg
+```
+
+```sh
+nix flake check --override-input barretenberg /home/phated/barretenberg
+```
+
+```sh
+nix flake check --override-input barretenberg github:phated/barretenberg/mybranch
+```
+
+### Without direnv
+
+If you have hesitations with using `direnv`, you can launch a subshell with `nix develop` and then launch your editor
+from within the subshell.
+
+__Note:__ If you aren't using direnv nor launch your editor within the subshell, your editor won't have the correct environment
+variables to find system dependencies and probably won't be able to build the project.

build.rs

@@ -92,6 +92,8 @@ fn main() -> Result<()> {
         .allowlist_function("acir_proofs_get_total_circuit_size")
         .allowlist_function("acir_proofs_init_proving_key")
         .allowlist_function("acir_proofs_init_verification_key")
+        .allowlist_function("acir_serialize_verification_key_into_field_elements")
+        .allowlist_function("acir_serialize_proof_into_field_elements")
         .allowlist_function("acir_proofs_new_proof")
         .allowlist_function("acir_proofs_verify_proof")
         .allowlist_function("pedersen_plookup_compress_fields")

cspell.json

@@ -13,6 +13,13 @@
         "consts",
         "acir",
         "schnorr",
-        "plookup"
+        "plookup",
+        "direnv",
+        "envrc",
+        "nixpkgs",
+        "clippy",
+        "subshell",
+        "phated",
+        "mybranch"
     ]
 }

default.nix

@@ -0,0 +1,13 @@
+let
+  lock = builtins.fromJSON (builtins.readFile ./flake.lock);
+  flakeCompatRev = lock.nodes.flake-compat.locked.rev;
+  flakeCompatHash = lock.nodes.flake-compat.locked.narHash;
+  flakeCompat = fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/${flakeCompatRev}.tar.gz";
+    sha256 = flakeCompatHash;
+  };
+  compat = import flakeCompat {
+    src = ./.;
+  };
+in
+compat.defaultNix