Show HN: PostFast – AI-Powered Copywriting Browser Extension

We built PostFast to simplify how creators and marketers generate platform‑specific copy. Instead of manually adapting the same product info for Twitter, LinkedIn, or a newsletter, you configure your product once, and PostFast uses AI to generate tailored content.

Key features: - One‑time setup for your product or service - Generates copy adapted to different platforms (style, tone, length) - Includes copy scoring and A/B variant comparison - AI-powered recommendations for which version to use - All inside your browser; no external app needed

It's built for indie makers, content teams, and marketers who need quick, consistent copy without jumping between tools. We focused on making it flexible and non‑opinionated—you control the inputs; the extension handles the formatting and platform nuances.

We're launching soon and opening a waitlist. If you regularly write promotional copy, we'd love your feedback on: - Which platforms you post to most - What kind of scoring criteria would be useful - Whether you'd prefer a free tier with limited generations

Waitlist and brief demo: [https://postfast.today/#subscribe]

(I’m one of the developers.)