Defining Array of Schema.Struct in a Class

Hi, new to Schema, have a question about defining an array of Schema.Struct. This works:

const Orders = Schema.Array(Schema.Struct({id: Schema.Number, ...}))

const Orders = Schema.Array(Schema.Struct({id: Schema.Number, ...}))

but this doesn't

class Orders extends Schema.Class<Orders>("Orders")(Schema.Array(Schema.Struct({id: Schema.Number, ...}))){}

class Orders extends Schema.Class<Orders>("Orders")(Schema.Array(Schema.Struct({id: Schema.Number, ...}))){}

It appears that the "fields" property needs a flat object structure. How can I define a schema representing an array of objects?