Progred

Progred is a projectional editor aimed at Inventing-on-Principle-style CAD/CAM: the editable source is structured data, and projections can present that data as code, controls, diagrams, or live geometry without translating it through a canonical source text.

The project is now a working native and browser prototype. It includes a small graph language, Grap; a projection stack; a continuation-based layout and event pipeline; and Puri backends for Vello and Canvas2D.

The stack

• GID is the native data substrate: cell references, blobs, lists, and records. Cell identity is separate from every naming convention. See docs/gid.md.
• Libraries add open conventions such as names, UTF-8 text, numbers, colors, geometry, and layout. None of these are GID primitives.
• Grap is a small graph-processing language embedded directly in GID. Its functions consume and produce GID values, while Rust functions supply the primitive operations and platform capabilities.
• Projections are composable partial functions with a raw projection at the root. A projection may redispatch children through the same stack, add a contextual projection, evaluate Grap, or produce a domain-specific view.
• Display and layout describe editable vector-graphics leaves and pretty-printer-like structure. Placement settles geometry before hover and rendering continuations run.
• Puri is the pure widget boundary. The normal renderer calls Vello or Canvas2D directly; recorders can reify the same final-tagless drawing language for tests and debugging. See docs/puri.md.

The current model and projection decisions are summarized in docs/model.md and docs/projections.md. The broader motivation is in MOTIVATION.md.

Run it

On macOS, use the repository's sandboxed build and runtime workflow:

make run

This is the development replacement for cargo run --release. It builds in an isolated directory, packages an ad-hoc-signed App Sandbox bundle, and launches that bundle. Other useful commands are:

make sandbox-check
make sandbox-test
make serve-web
make build-ipad

The browser build is served at http://localhost:8080; another device on the same network can use this machine's LAN address. Built-in documents are available from the Examples menu. The native iPad host and deferred spatial visionOS work are documented in docs/platforms.md.

Cargo build scripts and procedural macros execute dependency code. Ordinary Cargo commands in this repository intentionally stop at a tripwire; read docs/build-security.md before changing dependencies or bypassing the supplied commands.

Before distributing a build, review docs/release-checklist.md.

Sample documents under examples/ include:

• examples/sample.gid — editor and projection examples;
• examples/grap-demo.gid — Grap language constructs;
• examples/iop-tree.gid — the first tree from Bret Victor's Inventing on Principle, recreated as an editable Grap program and live drawing.

The checked-in GID notation is a temporary bridge for Git, debugging, and text-bound tooling. GID is intended to become its own non-textual binary stack; the bridge is documented in docs/gid-text.md.

Repository layout

• gid/ — GID values, cells, documents, and positions
• grap/ — Grap evaluator
• libraries/ — core Progred libraries and their vocabulary/FFIs
• display/ — display language
• ui/ — measurement, layout, Puri, and native/web drawing backends
• progred/ — editor application and projections
• docs/ — current design and implementation notes
• examples/ — checked-in GID example documents
• experiments/ — focused research retained alongside the main project
• reference/ — source material used to reproduce external examples

Prototype history

The former TypeScript, Swift, egui, Haskell, and nested Linebender prototypes were archived when this implementation took over the repository root. Their complete pre-promotion source tree is available at the remote tag archive/pre-root-promotion; archive/multi-prototype retains an earlier multi-prototype milestone.

To inspect the repository immediately before promotion without disturbing the current checkout:

git worktree add ../progred-before-promotion archive/pre-root-promotion

The most relevant design handoffs were retained in docs/history/.