biz59
Tools for developers, data people and small teams.
Biz59 LLC is a small company in New York. We build and run eleven products, most of them with one sign-in, and we write about what we see in software, AI and startups.
A database client, plus free data tools in the browser.
iPaid, i Owe: track what you owe and what is owed to you.
Security tools for small sites and teams, with one sign-in.
Short links, QR codes and page-view tracking.
An email router for apps, developers and bots.
Privacy policies, consent records and download/delete requests for apps and sites.
Website, policies, support pages, sign-in and cloud sync for your mobile app.
Offline-first cloud sync for your app's data, with sign-in for your users built in.
Our build agent: describe your app in a chat and watch it get built. Coming soon.
A whiteboard that also draws the diagram from your outline.
Markdown notes and documents that look good on screen and on paper.
More articles
SPF, DKIM and DMARC for a ten-person business in 2026: why invoices land in spam and the three DNS records that fix it
Why invoices sent through QuickBooks, Stripe or a CRM silently land in customer spam folders, the 10-lookup SPF limit that breaks email delivery, worked DNS records for your domain, and the 4-step path to p=reject.
The first foreign subsidiary of a small US company: cost-plus transfer pricing, the markup tax offices accept and the yearly paperwork
Why a service subsidiary bills its US parent cost plus a markup: India's published 15.5% safe harbour, Poland's 5% rule that does not cover software development, the Philippines' lack of one, the Form 5471 penalty ($10,000, up to $60,000 a year), local thresholds, and a worked year for a five-person Indian subsidiary with a year-end true-up.
The billing contact: who gets the invoice, the failed-payment email and the renewal notice at a small SaaS's business customers
When the card holder is not the user, Stripe, Chargebee and Paddle send billing mail to one address. What each can add, a failed annual renewal day by day, PO and net-30 handling, and a worked churn model with the arithmetic.