Cartly

Most online fashion stores in Bangladesh are a catalog and a checkout. Cartly asks what shopping would look like if a knowledgeable assistant came with the store: one that understands what you mean, speaks your language, shows you how a piece looks on you, and handles the cart for you, on top of the local payment and courier rails people actually use.

Three codebases: a Vue 3 storefront, a Vue 3 back-office, and a backend made of a NestJS 12 + Prisma commerce API (auth, catalog, cart, payments, delivery, returns, analytics) and a separate FastAPI service that owns everything AI. They share PostgreSQL 16 with pgvector, where the AI service keeps its own schema for product embeddings, and Redis for carts, assistant memory, rate limits, caches, and pub/sub events.

Pip runs on Claude with the catalog and persona in a cached system prompt, so most turns are a single call. Every reply is structured JSON (text, speech, products, actions, suggestion chips), and every product id and action is checked against the catalog before it reaches the shopper. A separate tool call with web search keeps trend answers current, cached per topic. Each turn carries the shopper's cart, orders, locale, season, and upcoming festivals, and Pip answers in the language and script the shopper used.

Every AI feature has a working fallback (a rule-based brain, a dependency-free embedder, browser speech), the storefront asks the API which capabilities are on, and every paid call is metered per feature against a daily budget. Evaluation scripts compare models on the same conversations and score try-on quality under a spend cap.

Payments cover bKash Tokenized Checkout, Nagad's encrypted merchant API, Rocket and cards through SSLCommerz, and cash on delivery, with gateway credentials encrypted at rest and orders marked paid only after server-side confirmation. Delivery integrates Pathao, Steadfast, and RedX, each with its own webhook authentication and a periodic sweep for missed updates, plus a phone-friendly rider app. Stock is checked and decremented inside the checkout transaction.

Cartly is a complete, tested platform ready to deploy, with a documented plan for scaling to 10,000 concurrent shoppers. Gateway and courier integrations are exercised against local stand-ins in the test suite.