Lorenzo PuricelliFounder and CEO
About us
Who builds Mastro, and where we want to take accounting firms
We started in autumn 2025 inside a few accounting firms, automating their bookkeeping. We want to reach the point where everyone in the firm, from the partner to the front desk, works with their clients without chasing anything, next to the accounting software they already use.
The people behind Mastro
Who we are and what we bring into Mastro: the product and the firms we work with every day.
Our office is at Corso di Porta Vigentina 13, in Milan.
We are a small team, looking for people who want to grow fast with us. Careers
How Mastro began
Mastro was born in autumn 2025 inside a few accounting firms, with tailor-made automations for their bookkeeping. Working there we saw where the time really goes, and it was almost all around the accounting software.
Certified mail to sort, documents to file by hand, deadlines without an owner, signatures and fees to chase: work that the people in the firm hold together by hand, every day.
So we built Prisma next to the accounting software, without asking anyone to change it: everyone in the firm finds their work already prepared, and clients sign, send documents and pay from their phone.
Our story
- Autumn 2025 · We start inside a few accounting firms, with tailor-made automations for their bookkeeping.
- Spring 2026 · The first product reaches firms: mail and certified mail, documents, deadlines and signatures next to their accounting software.
- Summer 2026 · The first firms pay, before the company even exists.
- August 2026 · We close our first investment round.
- September 2026 · We become Mastro, and Clerk books its first real invoices inside an accounting software.
- 5 October 2026 · Mastro S.r.l. is founded in Milan as an innovative startup.
- 18 November 2026 · Mastro launches in Milan, at the Google offices, in front of the firms.
Prisma
Who does what, when you work with Prisma
Your accounting software stays yours and keeps the books. All the work around it goes through here, from the client’s first message to the closed file.
- 1
Arrived
Certified mail, an email or a WhatsApp message from the client reaches Prisma from the inbox the firm already uses.
- 2
Recognised
Prisma works out which client it belongs to and which file, and if there is a legal term it highlights it.
- 3
Assigned
It goes to whoever looks after that client in the firm, with the deadline and the owner already set.
- 4
Prepared
The reply, the right folder and the document request arrive ready to be reviewed.
- 5
Approved
The person in the firm reads and decides: nothing goes to the client without their yes.
- 6
Closed
The client signs, sends documents or pays from their phone, and everything stays in your Drive, next to your accounting software.
The rules we work by
- 1
Your accounting software stays yours
No migration: clients are imported once and the books stay where you have always kept them.
- 2
Nothing goes out without your yes
AI proposes replies, folders and reminders, but it is always a person in the firm who sends them.
- 3
Your documents stay yours
They are filed in your Drive or OneDrive, in your folders, and stay there even if one day you leave Prisma.
Bring the whole firm to the demo
We work on your own clients: the partner sees where every file stands, whoever keeps the books finds their deadlines, the front desk finds today’s mail.