I spent a week building 10 Excel templates that actually calculate — post-mortem (and one is free)

Description and use

The author built 10 functional Excel templates with real formulas, automated validation, and launched a minimal storefront on Cloudflare Workers using TRC20 payments, offering a free version without an email wall.

Problem

Creating functional, formula-driven Excel templates that users can download and use without errors, while building a minimal storefront to sell them.

Outcome

The author successfully built 10 functional Excel templates, automated validation, and launched a minimal storefront with TRC20 payments, offering a free version without an email wall.

Workflow

• 1. Design templates with yellow input cells and formula-only cells.
• 2. Validate formulas headlessly using a formula-evaluation library, comparing results to expected values.
• 3. Build a Cloudflare Worker storefront that serves product pages and base64-encodes .xlsx files.
• 4. Implement unique-cent order matching via Tronscan API for payment verification.
• 5. Deploy and run link/asset checks to prevent broken preview images.
• 6. Offer a free lite version without an email wall to drive trust and conversions.

Evidence

All templates use real Excel formulas end-to-end; inputs are yellow cells, formulas elsewhere; validation is automated headlessly.

Source

Payments: USDT TRC20 straight to a wallet — non-custodial, no payment processor holding funds, no KYC.

Source