GLASSINVOICE
Disciplined Invoicing for UK Sole Traders
Most invoicing software is bloated — a wall of upsells, dashboards full of vanity metrics, and a monthly fee that quietly creeps up. A sole trader does not need an enterprise billing suite. They need a quiet, serious place to raise an invoice, track an expense, and understand where the money actually went, all in step with the UK tax year.
Origin Story
GlassInvoice started from a simple frustration: I wanted to run my own contracting books the way I run a studio — disciplined, calm, and free of clutter. The name nods to the glassmorphism in the interface, but the philosophy is the opposite of decorative: quiet typography, serious analytics, zero bloat. Built in the UK, for the UK sole trader.
How It's Built
The product is deliberately scoped. It is opinionated about the things that matter — clean ledgers, honest analytics, a tax year that is actually the British one — and it refuses to grow features for the sake of a comparison table. There is a full synthetic-data demo so you can try the whole thing without an account or a card, which also kept development honest about what a first-run experience should feel like.
Engineering Notes
Built around the UK tax year
The ledger is organised around the British tax year (2025/26) rather than a generic calendar, because that's the boundary a sole trader actually reconciles against. Analytics are framed the same way, so the numbers map directly onto what you'll eventually file.
Multi-currency from the data model up
Foreign-billed work is a first-class citizen: currency lives in the invoice and expense records themselves, not as a presentation-layer afterthought, so conversions and reporting stay correct rather than approximate.
Disciplined on purpose
There's a full synthetic-data demo — no card, no account — which kept development honest about the first-run experience. The product refuses to grow features for a comparison table; the restraint is the design.
GlassInvoice is what happens when you treat admin software with the same craft as a product you would actually want to use. Run your practice like a studio — the tooling should be calm, opinionated, and out of your way.
What It Does
The Ledger
A clean invoice and expense ledger organised around the UK tax year (2025/26). Raise, track and reconcile without wading through menus you will never use.
Serious Analytics
Revenue and expense analytics built to inform decisions, not to look impressive in a screenshot. You can see the shape of the year at a glance and drill in when you need to.
Branded PDF Export
Invoices export to clean, branded PDFs ready to send to a client. The output is as disciplined as the rest of the app.
Multi-Currency
Built-in multi-currency support for international clients, so foreign-billed work is a first-class citizen rather than an afterthought.
Expense Tracking
Capture and categorise expenses against the same ledger, with AI-assisted categorisation to take the friction out of bookkeeping.
Synthetic Demo
A full demo mode running on synthetic data — no card, no commitment. Sign in only when you are ready to keep your own books.
Where It Stands
GlassInvoice is live with a full synthetic-data demo, so it can be tried with no account. The roadmap follows the UK sole trader's real calendar — deeper VAT handling and a path toward Making Tax Digital — rather than feature breadth for its own sake.
GlassInvoice is a Next.js and TypeScript application styled with Tailwind CSS, leaning on a glassmorphism design system for its quiet, layered surfaces. Authentication is handled by Firebase Auth with Google sign-in, alongside a synthetic-data demo mode that needs no account at all. Firestore stores the ledger, invoices and expenses, with an AI assist layer for expense categorisation and insight. Invoices are rendered to branded PDFs on the client, and multi-currency handling is built into the data model rather than bolted on. Hosted on Firebase, tuned for the UK tax year.