Ledger
The internal tool your spreadsheet has outgrown
Built for: Small operators running the business out of one fragile file
Every small business has the spreadsheet: three people know how it works, one formula is load-bearing, and nobody dares restructure it. Ledger is that turned into a tool — the same records and reports, with validation that stops the bad entry before it's saved.
The S tier is local-first and single-user: your data stays on your machine, exports to JSON and CSV whenever you want, and there's no subscription and no server to trust. Step up to M when more than one person needs to be in it at once.
Single-user tool
Records, validation, reports, PDF output. Local-first, no account.
- Estimated hours
- 60 h
- Rate
- €50/h
- Delivered in
- 6 weeks
- Starting
- September 2026
- Your records, your fields, with validation that reflects your actual rules
- Reports and totals that used to be manual
- PDF output for anything you send to a customer
- Import from the current spreadsheet, export to JSON and CSV
- Runs in the browser; the data never leaves the machine
Multi-user tool
As S, plus accounts, roles and an audit trail on shared data.
- Estimated hours
- 110 h
- Rate
- €50/h
- Delivered in
- 11 weeks
- Starting
- September 2026
- Everything in S
- Accounts and roles: who can see it, who can change it
- Audit trail — who changed what, when, and what it was before
- Shared data with sensible conflict handling
- Daily backups you can actually restore, tested once in front of you
- Accountancy or tax advice — I encode the rules you or your accountant give me
- Migrating decades of historical records without a per-case look
- Supabase or hosting subscriptions for the M tier
- The current spreadsheet, warts included
- The rules that live in someone's head rather than in the file
- One person who can say what 'correct' means
Things I've already shipped that this leans on.
Sole Ledger
Mobile appThis is the package, built for my own company: time, expenses, invoices, PDF output and a live tax reserve, on a single-file SQLite database with no server.
Read the case study →kakeibo 家計簿
Web appA tested double-entry engine where the UI refuses to post an unbalanced entry. Validation that prevents bad data beats reports that find it later.
See it in the work →Not sure this is the right one?
Then don't order it yet. A €300 Spec Sprint gets you a written, fixed-scope plan with the hours in it, and the whole €300 comes off whichever package we land on. That's the honest order to do this in.
40% deposit, 40% at the agreed midpoint, 20% on handover. All prices ex. VAT. Dutch customers pay 21%; EU businesses with a valid VAT number are invoiced at 0% under the reverse-charge rule.