Describe the bug

The generated Database types include an __InternalSupabase property that doesn't conform to the schema structure:

// Generated database.types.ts export type Database = { public: { Tables: { ... } Views: { ... } // etc. } __InternalSupabase: { PostgrestVersion: "12.2.3 (519615d)" } }

The __InternalSupabase object has PostgrestVersion but no Tables, Views, etc. This breaks generic constraints for libraries that want to accept any valid Database type.

Library affected

supabase-js

Reproduction

No response

Steps to reproduce

// Library code trying to accept any Supabase Database type interface SchemaDefinition { Tables: Record<string, { Row: object; Insert: object; Update: object }> Views?: Record<string, { Row: object }> // etc. } interface DatabaseSchema { public: SchemaDefinition [schemaName: string]: SchemaDefinition // Index signature } // This fails because __InternalSupabase doesn't have Tables function query<DB extends DatabaseSchema>(client: SupabaseClient<DB>) { ... }

Error:

Type 'Database' does not satisfy the constraint 'DatabaseSchema'. Property '__InternalSupabase' is incompatible with index signature. Property 'Tables' is missing in type '{ PostgrestVersion: "12.2.3 (519615d)"; }' 

Expected behavior

Third-party libraries should be able to define generic constraints on database types without workarounds.

Current workaround

We use Omit<Database, '__InternalSupabase'> everywhere (same pattern as in SupabaseClient source), but this:

1. Requires every library to know about this internal implementation detail
2. Forces use of any in index signatures, losing type safety for custom schemas
3. Adds complexity for library consumers

Suggested solutions

Option 1: Separate internal metadata type

export type Database = { public: { Tables: {...} } // Custom schemas work with index signature } // Separate from Database type export type DatabaseMeta = { __PostgrestVersion: string }

Option 2: Symbol key instead of string key

declare const __internal: unique symbol export type Database = { public: { Tables: {...} } [__internal]?: { PostgrestVersion: string } // Symbol keys don't affect string index signatures }

Option 3: Branded/tagged type

export type Database = { public: { Tables: {...} } } & { __brand?: { PostgrestVersion: string } } // Intersection doesn't pollute index signature

System Info

- supabase-js version: 2.x - TypeScript version: 5.x

Used Package Manager

pnpm

Logs

• supabase-js version: 2.x
• TypeScript version: 5.x

Validations

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• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Supabase JS Library issue and not an issue with the Supabase platform. If it's a Supabase platform related bug, it should likely be reported to supabase/supabase instead.
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• The provided reproduction is a minimal reproducible example of the bug.