Case study · My own back office
WLBS Finances: invoices, payments and estimates, run from WhatsApp and from Claude
The app that runs the business side of my work. Clients never make an account, money chases itself, and I can ask Claude who owes me and have it record the payment.
The brief
Invoicing an Indian client properly is fiddly: the right GST split, TDS, credit notes, amounts in words. Chasing payments is worse.
The first version was a plain PHP invoicer. Version 2 is a rewrite around one idea: everything a client needs arrives on WhatsApp as a link to a page built for a phone.
What I built
No accounts for clients
A WhatsApp message with a link, then a one-time code. Estimates, progress, statements and payment pages, each built for a phone. Links expire and can be renewed.
GST done right
CGST and SGST in Maharashtra, IGST elsewhere, nothing for exports under LUT. TDS, credit notes, Indian number grouping and amounts in words.
Money chases itself
Reminders on the due date, 3 days after, 7 days after, then weekly. They stop the moment the client pays or taps “I’ve paid”.
Clients see progress without asking
An update when approved hours cross 50%, 80% and 100% of the estimate.
Devs log hours from their phones
A reminder at the end of the day with a sign-in link, and their payouts in one place.
Ask Claude
An MCP server so I can run it from Claude: who owes me, record a payment, match a bank line, draft an invoice. Nothing can delete, every change is logged “via Claude”, and anything that messages a client asks me first.
The switch-over
Version 2 took over on 27 Sep 2026 from the old app, sharing the same data. Before the switch, an import copied everything across and compared both sides: every invoice and every rupee matched.
The part I loved
“Typing “who owes me?” into Claude and getting the answer from my own books.”
Credits
- Design, build and lead
- Anshul Laikar
- With help from
- Parag Dharadhar, Manish Fenin, Jyotirmoy Roy
- Live
- finances.wlbs.dev (private)
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