steprs.dev

STEP pre-flight before CAM — drop a file, check units, holes, stock, and machine/tool fit. Runs in your browser; nothing uploads.

Open-core Rust WASM parser (Apache-2.0).

Architecture

Browser UI (Next.js + three.js preview)
    ↓ File bytes (Web Worker — zero main-thread compute)
    ↓ WASM StepParser
pipeline::run_pipeline
  L0+L1  ingest_step (single DATA scan → prescan + arena)
  L3     topology::TopologyIndex (face IR + edge-indexed AAG)
  L4     features::extract_quoting_report (tiers 1–3)
  L6     aag::analyze_aag (petgraph on shared topology)
  L7     mesh::tessellate_mesh (optional)
  L8     labels::classify_face_labels (topology-based face labels, engine topology-v2)
    ↓ JSON ParseResult
UI workbench (Header · Holes · Stock · Pre-Flight · AAG)

OCCT preview mesh is display-only. Hole counts, stock envelope, and AAG export come from the Rust WASM parser.

Module map (crates/steprs-core/src/)

Module	Role
core/	Shared constants (DENSITY_THRESHOLD, MAX_MESH_TRIANGLES, stage labels)
parser/	nom ingest + scan utilities + single-pass ingest_step
arena/	Adaptive dense Vec / sparse HashMap storage
topology/	Parse IR — FaceRecord, edge-indexed adjacency graph (built once)
pipeline/	ParseContext, ParseOptions, run_pipeline, cancellation
features/	Quoting, AAG, mesh, label heads (all read ParseContext)
output/	Serde JSON contract
wasm/	Thin wasm-bindgen surface

Production defenses

• Sparse ID arena: pre-scan density gate → dense vs sparse allocation
• Committed WASM: apps/web/public/wasm/* rebuilt after Rust changes
• 50 MB warning before parse; parse cancellation via worker cancel message
• Real progress: WASM setProgressHandler emits L0–L8 stage strings

Development

yarn install
yarn build:wasm    # after any Rust change — commits artifacts to public/wasm/
yarn dev           # Next.js app in apps/web
yarn test          # cargo test + golden suite (see CONTRIBUTING.md)
yarn test:downloads # batch table against ~/Downloads STEP files

Web app layout and routes: apps/web/README.md.

Contributing: CONTRIBUTING.md — scope, test matrix, NIST fixtures.

Agent / reviewer context: llm.json — architecture, eval, open vs proprietary scope. Competitive AI boundary: docs/COMPETITIVE_BOUNDARY.md.

Batch validation

# Human-readable table for any directory
cargo run --example batch_parse --manifest-path crates/steprs-core/Cargo.toml -- ~/Downloads

# Include live Downloads in cargo test
STEPRS_DOWNLOADS_DIR=~/Downloads cargo test --manifest-path crates/steprs-core/Cargo.toml

WASM API

const parser = new StepParser();
parser.setProgressHandler((stage) => console.log(stage));
parser.parse(bytes);                    // full pipeline
parser.parseQuotingOnly(bytes);         // skip mesh + labels
parser.parseWithOptions(bytes, false, true); // mesh off, face labels on
parser.cancel();                        // abort in-flight parse

CI

.github/workflows/ci.yml:

1. rust-wasm — fmt, tests, golden suite, scorecard, schema drift, clippy (--no-default-features)
2. wasm-freshness — WASM rebuild diff + smoke test (all strict snapshots)
3. web — lint, typecheck, unit tests, Playwright E2E, next build

SEO endpoints

URL	Purpose
/robots.txt	Crawler rules, AI bot allowances, sitemap
/sitemap.xml	Search engine index
/llms.txt	Curated AI context (llmstxt.org)
/llms-full.txt	Extended product/architecture summary
/manifest.webmanifest	PWA metadata
/og-image.png	Open Graph / Twitter card (1200×630)
/privacy	Privacy policy

JSON-LD: WebSite, SoftwareApplication, WebPage, FAQPage on every page.

License & open core

steprs-core (Rust WASM parser) is Apache-2.0.

The hosted app, geometry editor, and future cloud APIs are proprietary — see OPEN_CORE.md for what is open vs closed.

The geometry editor is not in this public repository — Edit tab shows “Coming soon”. See docs/PRIVATE_EDITOR.md.