prisma-to-ecto

Convert Prisma schemas into Elixir Ecto schemas and migrations.

prisma-to-ecto is a CLI tool that reads a Prisma schema.prisma file and generates:

• Ecto schemas (.ex)
• Ecto migrations (.exs)
• Enum modules
• Join tables for implicit many-to-many relations
• View schema stubs

It helps teams migrating from Prisma → Elixir / Phoenix / Ecto or maintaining a Prisma-first schema workflow.

Installation

Global Installation (Recommended)

npm install -g prisma-to-ecto

Run the CLI:

prisma-to-ecto convert

Local Installation

Install inside your project:

npm install --save-dev prisma-to-ecto

Run using npx:

npx prisma-to-ecto convert

Project Structure

Your project only needs the Prisma schema.

Example:

my-project/
├── prisma/
│   └── schema.prisma
├── lib/
│   └── my_app/
├── priv/
│   └── repo/
│       └── migrations/
└── package.json

Only prisma/schema.prisma is required.

Place Your Prisma Schema

Create the Prisma directory if it doesn't exist:

mkdir -p prisma

Place your schema at:

prisma/schema.prisma

Running the Converter

Default Conversion

npx prisma-to-ecto convert

Default output:

Schema: ./prisma/schema.prisma
Schemas → ./prisma-to-ecto/schemas
Migrations → ./prisma-to-ecto/migrations

Custom Output Directories

npx prisma-to-ecto convert ./prisma/schema.prisma \
  --schema-out ./lib/my_app \
  --migration-out ./priv/repo/migrations

Generate Schemas Only

npx prisma-to-ecto convert --no-migrations

Generate Migrations Only

npx prisma-to-ecto convert --no-schemas

CLI Help

npx prisma-to-ecto --help

Example Output

prisma-to-ecto
  Schema:    ./prisma/schema.prisma
  Schemas →  ./lib/my_app
  Migrations → ./priv/repo/migrations

Parsed 20 model(s), 8 enum(s)

Generating Ecto schemas...
  ✓ user.ex
  ✓ task.ex
  ✓ project_stats.ex
  ... (28 total files)

Generating migrations...
  ✓ ..._create_users.exs
  ✓ ..._create_tasks.exs
  ✓ ..._create_label_task.exs
  ... (23 total files)

✓ Done!

Generated Files

Example structure:

lib/my_app/
├── user.ex
├── task.ex
├── notification_preference.ex
├── audit_log.ex
└── user_role.ex

priv/repo/migrations/
├── ..._create_users.exs
├── ..._create_tasks.exs
├── ..._create_label_task.exs
└── ..._create_view_project_statses.exs

Supported Prisma Features

The converter supports advanced Prisma schema features.

| Feature | Example | | ------------------------- | -------------------------------- | | UUID primary keys | @id @default(uuid()) | | Database schemas | @@schema("auth") | | Referential actions | Cascade, SetNull, Restrict | | Named relations | Task.assignee, Task.reporter | | Self-referential models | Task.subtasks | | Database annotations | @db.VarChar(320) | | Full-text indexes | @@fulltext | | Enum mapping | @map | | Composite primary keys | @@id([userId, channel]) | | Custom table names | @@map | | Views | view ProjectStats | | BigInt | Attachment.sizeBytes | | Decimal | Invoice.amountCents | | JSON fields | Json | | Implicit many-to-many | Task ↔ Label | | Sensitive field detection | password / secret / token |

Manual Review After Conversion

The generator may add TODO comments for items requiring manual review.

| Item | Location | Action | | -------------- | -------------------- | --------------------------------------- | | Foreign keys | User.assignedTasks | Set correct foreign_key: | | Database views | View migration | Write SQL query | | Enums | Migrations | Create Postgres enum type or use string |

Example package.json Script

Add a shortcut command:

{
  "scripts": {
    "convert": "prisma-to-ecto convert"
  }
}

Run with:

npm run convert

Using With Phoenix / Ecto

After generating migrations:

mix ecto.migrate

License

MIT