TypeScript Types

inz gen types turns instancez.yaml into a database.types.ts file. Pass its Database type to createClient and supabase-js types every from(), insert(), update() and rpc() call.

It reads only the yaml. There is no database or network call, so the output is correct even before you migrate.

inz gen types --out database.types.ts

import { createClient } from '@supabase/supabase-js'
import type { Database } from './database.types'

const supabase = createClient<Database>('http://localhost:8080', process.env.INSTANCEZ_PUBLISHABLE_KEY!)

const { data } = await supabase.from('todos').select('id, title') // typed rows
await supabase.from('todos').insert({ title: 'ship it' })         // checked against Insert

The output has the same shape as supabase gen types typescript: Tables with Row, Insert, Update and Relationships, plus the Tables<>, TablesInsert<> and TablesUpdate<> helpers and a Constants export. The file is a runtime module because of Constants, so name it .ts, not .d.ts.

Flags

See the CLI reference. public is always emitted, even when empty, plus every other schema that has a table. Unset ${INSTANCEZ_ENV_*} references are fine in string fields, so you need no secrets to generate types.

Column types

Column types come from the list inz validate accepts. In rpc args and returns, the longer spellings (int2, int4, int8, float4, float8, character varying, character, timestamp with time zone, timestamp without time zone, time without time zone, time with time zone) map to the same types.

Postgres	TypeScript
smallint, integer, int, serial, smallserial, bigint, bigserial, real, double precision, float, numeric, decimal	number
boolean, bool	boolean
json, jsonb	Json
text, varchar, char, uuid, date, timestamp, timestamptz, time, timetz, interval, money, inet, cidr, macaddr, bytea, xml, point, tsquery	string
bit, line, box, polygon, circle, tsvector, anything else	unknown

macaddr8, lseg, path, bit varying and range types such as int4range work only in rpc args and returns, where macaddr8 is string and the rest are unknown. inz validate rejects them as column types.

Types are matched case-insensitively. Parameters are ignored (varchar(255), numeric(10,2)), and text[] becomes string[]. An enum: column is a union of string literals.

Row is nullable (T | null) unless the column is required, a primary key, or a serial type. In Insert, a column is optional when it has a default, is serial, or is nullable. Update makes every column optional, and an immutable column becomes never.

RPC return types

Functions from rpc: are typed under public.

• void returns undefined.
• A scalar returns its mapped type T. A SQL NULL still arrives as null. record, composite and schema-qualified names are unknown.
• setof <table> returns that table’s Row[] plus SetofOptions; a leading public. is ignored. An unknown table name, or a schema-qualified name other than public., gives Record<string, unknown>[].
• setof <scalar> returns { fn_name: T | null }[].
• table(...) returns inline objects, with every field | null.

Differences from Supabase

• Enums and Constants.*.Enums stay empty because instancez enums are CHECK constraints; columns use inline unions.
• setof <scalar> returns { fn_name: T | null }[], which is the shape the REST layer sends.
• bit, geometric types other than point, tsvector and range types arrive as Postgres text strings but stay unknown, to match Supabase.
• Every relationship has isOneToOne: false, so a reverse embed is typed as an array. The server always returns an array for reverse embeds, even for a unique foreign key.
• rpc functions appear only under public, where instancez creates them.
• No __InternalSupabase block.
• Embeds across schemas work at runtime, since the server serves them, but are not typed because relationships are same-schema only. Cast the result to type them.
• auth and storage are not typed, so FKs to auth.users.id produce no relationship (Supabase does the same).
• functions: (code functions) are not typed.

Keep it in sync in CI

Commit database.types.ts and fail the build when it drifts from the yaml:

- run: inz gen types | diff - database.types.ts