MailCheap is a newsletter app you host yourself that writes, sends, and publishes your issues while charging you only for the emails you actually send, not for subscribers who never open anything. Write in an editor with slash commands, images, and content boxes, or send Markdown and HTML emails through the API, then work through a pre-send review that flags subject, preview text, unsubscribe link, and sender problems first. Bring your audience with you: CSV exports from beehiiv, Substack, Mailchimp, Kit, MailerLite, Buttondown, Ghost, and EmailOctopus import with each reader's status and signup date intact. Imports clean themselves, dropping invalid, misspelled, duplicate, throwaway, and spam-trap addresses, and a server-wide never-email list keeps known bad addresses out of every future import, signup, and send. Sending protects your domain: new contacts receive issues in paced steps, sends pause when bounce or complaint rates climb, and Gmail spam rates are watched daily. Every issue becomes a page on your newsletter's website, with a signup form, author page, share images, and a sitemap. Run up to three newsletters per account, each with separate contacts and campaigns, and follow subscribers over time with open and click reports by inbox provider. AI agents can do anything the dashboard can through the MCP server, and scripts get the same reach through the REST API, with sending marked irreversible so agents ask first. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.