SkyLang Studio - Sovereign Web App Studio

🧶 Loom Specification Code

✔ Z3 SMT Invariants Verified

// ============================================================================
// SKYLANG LOOM SPECIFICATION PLAYGROUND (skylang.dev/studio.html)
// ============================================================================
// High-level declarative intent, relational stores, views & SMT proofs.

system SkyBnbMarketplace {
  entity Listing {
    id: UUID @primary_key
    title: String @max_len(128)
    city: String @max_len(64)
    rating: Float @precision(2)
    nightly_rate: Int @range(1, 10000)
    category: String @enum(["beachfront", "cabins", "views", "castles"])
  }

  entity Booking {
    id: UUID @primary_key
    listing_id: UUID @foreign_key(Listing.id)
    nights: Int @range(1, 90)
    total_price: Int
  }

  view ListingMarketplaceGrid {
    query: ListingStore.all()
    route: "/stays"
  }

  view DedicatedListingDetailView {
    query: ListingStore.get(id)
    route: "/stay/:id"
    hero: PhotoGalleryGrid
    amenities: ["WiFi", "Pool", "Kitchen", "Parking", "FirePit", "AC"]
  }

  view HostListingPageView {
    route: "/host"
    action: CreateListing
  }

  store ListingStore: Relational<Listing> @persistent
  store BookingStore: Relational<Booking> @persistent

  contract ReserveStay(listing_id: UUID, nights: Int) {
    guarantee: Atomic
    guarantee: NonReentrant
    proof: Z3TheoremSolver.verifyNoOverflow()

    onExecute {
      ensure nights > 0 else reject("INVALID_NIGHTS")
      ensure ListingStore.exists(listing_id) else reject("NOT_FOUND")
      let listing = ListingStore.get(listing_id)
      let total = (listing.nightly_rate * nights) + 45
      BookingStore.insert({ id: UUID.random(), listing_id, nights, total_price: total })
    }
  }

  contract CreateListing(title: String, city: String, nightly_rate: Int, category: String) {
    guarantee: Atomic

    onExecute {
      ensure nightly_rate > 0 else reject("INVALID_RATE")
      ListingStore.insert({ id: UUID.random(), title, city, rating: 5.0, nightly_rate, category })
    }
  }
}

👁️ Live Preview

📄 Emitted Source Code

Engine: ⚡ Loom Sandboxed Engine

🔒 https://skybnb.skylang.dev/stays

🛡️ Isolated Loom Sandbox

⚡ All Stays

🏖️ Beachfront

🏕️ Cabins

⛰️ Amazing views

🏰 Castles

Malibu Villa Ocean Suite

★ 4.98 (124 reviews) • Malibu, California • Superhost

📸 Ocean Panorama Suite

🏊 Infinity Pool

🍳 Chef's Kitchen

👤

Hosted by Elena Vasquez

Superhost • 4 years hosting • 100% Response Rate

What this place offers

📶 Ultra-fast 1 Gbps Fiber WiFi

🏊 Private Heated Infinity Pool

🍳 Gourmet Kitchen & Espresso Bar

🅿️ Free On-Site Gated Parking

🔥 Oceanfront Outdoor Fire Pit

❄️ Central Climate Control AC

About this space

Immerse yourself in panoramic coastal luxury. This architectural sanctuary offers floor-to-ceiling glass walls, zero-edge pool access, and atomic transactional stay guarantees powered directly by SkyLang state engines. Perfect for focused retreats and luxury getaways.

$380 / night

★ 4.98

Check-in / Nights

$380 × 3 nights $1,140

Cleaning & Service Fee $45

Total $1,185

✔ Atomic SMT Contract Execution Guaranteed

🗄️ SkyLang Entity Store: Relational<Listing>

Database Persistence Driver: SQLite / WASM SharedArrayBuffer

6 Active Records

Auto-Generated DDL Migration (Loom Relational Compiler)

CREATE TABLE listing (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  title VARCHAR(128) NOT NULL,
  city VARCHAR(64) NOT NULL,
  rating DECIMAL(3, 2) DEFAULT 5.0,
  nightly_rate INT NOT NULL CHECK (nightly_rate > 0),
  category VARCHAR(32) NOT NULL
);

CREATE TABLE booking (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  listing_id UUID REFERENCES listing(id),
  nights INT NOT NULL CHECK (nights > 0),
  total_price INT NOT NULL
);

Live Record Table (`ListingStore`)

ID	Title	City	Rating	Nightly Rate	Category