Goldy: GPU runtime for the Fondaco Machine

Goldy is a Rust GPU library that realizes the Fondaco Machine on modern hardware. Merchants describe parcels (data) and schemes (computation with ownership-derived ordering); Goldy manages the physical medium, schedules dispatches, and mediates all foreign interaction through exchanges.

Maturity: Goldy 0.2 is the Fondaco Machine public API. SemVer applies within 0.2.x; expect breaking changes at 0.3. Python bindings remain alpha; Rust is the primary surface.

Why Fondaco?

Traditional GPU APIs expose descriptors, barriers, render passes, and swapchain plumbing. The Fondaco model is different.

Goldy makes that model practical on 2020+ GPUs:

What Goldy ships today

• Scheme-first API — record once, submit every frame; barriers and transient aliasing derived automatically
• Typed bindless shaders — Slang with [goldy_compute], [goldy_vertex], [goldy_fragment] and goldy_exp access patterns (Scattered, Broadcast, Interpolated, …)
• Compute-to-surface — compute shaders write swapchain drawables directly; no raster pass required
• Native backends — Vulkan 1.4+ (Windows, Linux), DX12 (Windows), Metal Tier 2+ (macOS); no MoltenVK
• Multi-language bindings — Rust (primary), Python, .NET, C++
• 21 Rust examples — triangle, compute particles, Game of Life, plasma, multi-window, and more

Not yet shipped (see runtime mapping for status): yielding scripts, $yield petitions, scheme fusion/splitting, defragmentation, WASI host integration.

Quick example: compute-to-surface

use goldy::{
    Buffer, BufferKind, ComputePipeline, Context, DeviceDescriptor, Instance,
    NodeAccess, RequestAdapterOptions, RetainedPool, Scheme, ShaderModule,
    SurfaceConfig, SurfaceExchange, Transaction,
};

let instance = Instance::new()?;
let device = instance
    .request_adapter(&RequestAdapterOptions::default())?
    .request_device(&DeviceDescriptor::default())?;
let ctx = device.create_context()?;
let pool = RetainedPool::new(&device)?;
let surface = SurfaceExchange::new(&ctx, &window, SurfaceConfig::default())?;

let shader = ShaderModule::from_slang(&device, COMPUTE_SHADER)?;
let pipeline = ComputePipeline::new(&device, &shader)?;
let uniforms = pool.alloc_buffer_with_data(&device, &uniforms_data, BufferKind::Broadcast)?;

let mut scheme = Scheme::new(&ctx);
let present = surface.bind_destination(&mut scheme)?;
scheme
    .node("render", &pipeline)
    .with_parcel(&uniforms, NodeAccess::Read)
    .with_present(&present.0)
    .dispatch(wg_x, wg_y, 1);

// Each frame:
let mut submission = scheme.submit()?;
present.1.claim(&mut submission)?.consume()?;

Windowed examples require the examples feature:

cargo run --features examples --example compute_to_surface --release

cargo run --features examples --example triangle --release

Architecture

Merchant (schemes + parcels)
        │
        ▼
   Scheme / GraphIR  ←── wave & partition analysis, retention
        │
        ▼
  RetainedPool / TransientPool / VramAllocator
        │
        ▼
  Vulkan │ DX12 │ Metal   ←── Slang → SPIR-V / DXIL / MSL
        │
        ▼
  Exchanges (present, readback)

Goldy abstracts where bytes live (Layer A: medium) but exposes what access costs (Layer B: coalescing, occupancy, residency). See the design thesis.

Installation

[dependencies]

goldy = "0.2"

Slang is embedded at build time and extracted at runtime — application developers do not install Slang separately. Set GOLDY_SLANG_PATH only to override. Maintainer bump procedure: slang/manifest.json + slang/download.sh.

Release packaging and shader debugging notes live in the GitHub repo.

Platforms

Override backend: GOLDY_BACKEND=vulkan|dx12|metal.

Minimum hardware: Vulkan 1.4+, DX12 with Enhanced Barriers, Metal Argument Buffers Tier 2+. See Target Hardware.

Documentation

• 📖 Documentation — tutorials, programming model, backends, bindings
• 📖 Fondaco Machine spec — normative abstract machine
• 📖 Goldy runtime mapping — what Goldy implements today vs designs in progress
• 📖 API reference — Rust docs

Development

cargo fmt --all -- --check

cargo clippy -- -D warnings

GOLDY_VALIDATION=all cargo test

Run all examples: ./run_all_examples.sh (requires --features examples).

License

MIT — see LICENSE.

Author

Mohamed Koubaa