Schema Viz

0.3.3 verified Sat May 09 auth: no javascript

Universal database schema visualizer that takes a schema file or directory and generates an interactive ER diagram in the browser with pan, zoom, and live reload. Currently at version 0.3.3, released monthly-ish. Supports Prisma, Laravel migrations, TypeORM, Drizzle ORM, JSON, and live PostgreSQL/MySQL introspection. Key differentiator: auto-layout based on FK-graph BFS, Figma-style select/edit modes, drag-and-drop persistence via share files, and framework detection with logos in the toolbar. Works as a CLI tool (global install) and runs a local server. No SaaS required.

Common errors

error Error: Cannot find module 'schema-viz' ↓

cause Global install failed or not in PATH; using npx without installing usually works but may pull an older version.

fix

Run 'npm install -g schema-viz' or use 'npx schema-viz' with an explicit version (e.g., npx schema-viz@0.3.3).

error Error: No parser detected for path './migrations' ↓

cause The tool couldn't auto-detect a supported schema format in the given directory.

fix

Specify --parser flag with the correct parser ID (e.g., --parser=laravel for Laravel migrations). Ensure files have expected extensions (.prisma, .json, .entity.ts, etc.).

error Port 7337 is already in use ↓

cause Another instance of schema-viz or other process is using the default port.

fix

Use --port flag to choose a different port (e.g., --port=8080).

Warnings

gotcha Layout resets on every schema change before v0.3.2. Update to >=0.3.2 to preserve table positions across edits. ↓

fix Upgrade schema-viz to version 0.3.2 or later.

breaking Parser auto-detection may pick the wrong parser if multiple schema formats are present in the same directory. Use --parser flag to force a specific parser. ↓

fix Specify --parser=prisma|laravel|typeorm|drizzle|json explicitly.

deprecated The --auto-open flag is deprecated in favor of --autoopen (without hyphen). Both work currently, but --auto-open may be removed in a future release. ↓

fix Use --autoopen instead of --auto-open.

gotcha URL-based introspection requires a live database; if the URL is unreachable, the tool hangs silently until timeout. Use a valid connection string with proper credentials. ↓

fix Test connection with psql or mysql client before using --url.

Install

npm install schema-viz

yarn add schema-viz

pnpm add schema-viz

Imports

default
wrong
```
const schemaViz = require('schema-viz')
```
correct
```
import schemaViz from 'schema-viz'
```
ESM-only since v0.3.0; CLI usage is via npx or global install, not programmatic imports.
run
wrong
```
const run = require('schema-viz').run
```
correct
```
import { run } from 'schema-viz'
```
Programmatic API is experimental; run() starts the server. Use CLI for normal usage.
type definitions
```
import type { Schema, Table } from 'schema-viz'
```
TypeScript types are exported for use in plugins or custom parsers.

Quickstart

Launches an interactive ER diagram for a Prisma schema file, auto-opens browser.

npx schema-viz ./prisma/schema.prisma --port=8080 --autoopen