-- Your SQL goes here

CREATE TABLE persons (
    id              SERIAL      PRIMARY KEY,
    email           text        NOT NULL UNIQUE,
    display_name    text        NOT NULL,
    created_at      timestamp   NOT NULL DEFAULT current_timestamp
);

/*          This table doesn't exist
            ↓↓↓↓↓↓↓                     */
ALTER TABLE recipes
    ADD COLUMN author_person_id int NULL
        REFERENCES persons (id) ON UPDATE CASCADE ON DELETE CASCADE;