San Francisco, Calif.-based Writer, a company that provides an AI-based writing assistant for business use cases like marketing and documentation, has raised a $21 million Series A funding round.

The financing was led by Insight Partners. Gradient Ventures, the Todd & Rahul Angel Fund, Scott Belsky, Oliver Jay, Jack Altman, Allison Pickens, Packy McCormick, Lenny Rachitsky, Austin Rief, Ankur Nagpal, Alex MacCaw, Camille Ricketts, Vivek Sodera, Julia Lipton, and James Beshara also participated in the investments.