Default Tech Stack

Every Web project the build agent produces uses the same stack, and it is fixed rather than selectable.

This is what the agent is instructed to build, not a guarantee of what a given project contains. It is a standing instruction in the agent’s prompt, so a project that was steered elsewhere can differ.

The Stack

Layer	Technology
Frontend	React (Vite, Tailwind CSS, Wouter)
Backend	Node.js + Express
Database	PostgreSQL + Drizzle ORM
State	React Query
Auth	JWT on protected routes
Containers	Docker, via `docker-compose.yaml`
Gateway	Nginx reverse proxy, version 2 projects only

The Create Project form states it more briefly, as Made with React, Node.js, and PostgreSQL.

The Create New Project drawer with Web Application selected, showing a single pre-selected Platform Type radio whose label reads Made with React, Node.js, and PostgreSQL. — The stack is stated on the Create Project form. It is a description, not a choice; Web projects have one option.

Two Project Versions

Projects carry a prompt version that changes the architecture the agent builds.

	Version 1 (original)	Version 2 (gateway)
Entry point	Each service on its own host port	Nginx reverse proxy, single entry point
Exposed ports	Frontend and backend both exposed	`nginx` (primary) and `database`
Application URL	One URL per service	A single subdomain URL
Subdomain proxying	Not eligible	Eligible

New projects are created at version 2. Version 1 projects continue to work and are not migrated.

Conventions the Agent Follows

Convention	Rule
Persistence	PostgreSQL for all persistent data. No in-memory or mock stores
Configuration	Every credential, constant, port, and host in a root `.env`, referenced from `docker-compose.yaml`. No hardcoded secrets or URLs
Env var names	`DATABASE_EXTERNAL_PORT`, `DATABASE_USERNAME`, `DATABASE_PASSWORD`, `DATABASE_NAME`. Alternates such as `POSTGRES_USER`, `DB_PORT` and `FRONTEND_PORT` are disallowed
Validation	Applied in both the frontend and the backend
Internal secrets	`JWT_SECRET`, database credentials, session and encryption keys are auto-generated
External secrets	Third-party service keys are requested from you; see Credentials
Repository contents	Code only. Anything describing the project is produced as a knowledge document, not committed

Version 2 Project Layout

Version 2 projects add an nginx/ directory containing a production reverse-proxy configuration and its own Dockerfile based on nginx:alpine. Every service in docker-compose.yaml follows a fixed port-exposure pattern, and the gateway and database are the services that expose ports externally.

Your Next Step

The stack is fixed, but what the agent does with it is governed by a longer set of rules.

See how the agent works

Its tools, its operating rules, and the limits it works within.

Inspect the generated code

Browsing the codebase and querying the database.

Build Mode

Prototype Mode

Working in a project

Default Tech Stack

The Stack

Two Project Versions

Conventions the Agent Follows

Version 2 Project Layout

Your Next Step

See how the agent works

Inspect the generated code

​The Stack

​Two Project Versions

​Conventions the Agent Follows

​Version 2 Project Layout

​Your Next Step

See how the agent works

Inspect the generated code

The Stack

Two Project Versions

Conventions the Agent Follows

Version 2 Project Layout

Your Next Step