SaaS / FinTech
Billwise
A billing and invoicing platform that helps freelancers and small agencies manage clients, track time, and get paid faster through Stripe and PayPal.
Overview
Billwise is a billing platform built specifically for freelancers and small agencies who outgrew spreadsheets but don't need the complexity of enterprise invoicing tools. It handles the full cycle: time tracking, invoice generation, payment collection via Stripe and PayPal, and automated reminders for overdue invoices.
The Problem
Most invoicing tools are either too simple (no recurring billing, no time tracking) or too complex (built for enterprises with procurement workflows). Freelancers need something in between: professional invoices, multiple payment options, and automatic follow-ups, without a 30-minute onboarding flow. The existing market leaders also charge percentage-based fees on top of payment processor fees, cutting into already thin margins.
Approach
Multi-gateway payment integration
Integrated both Stripe and PayPal as payment options on every invoice. Clients choose how they want to pay. Stripe handles card payments and SEPA direct debits for European clients. PayPal covers the rest. Webhook listeners on both gateways update invoice status in real time, so the dashboard always reflects the current payment state.
Invoice templating engine
Built a template system where users design their invoice layout once, then every invoice auto-populates with client details, line items, tax calculations, and payment links. Templates support custom branding: logo, colors, fonts, and footer text. PDF generation runs server-side through Puppeteer for pixel-perfect output.
Automated payment reminders
Overdue invoices trigger a configurable reminder sequence. Users set the cadence (3 days, 7 days, 14 days after due date) and tone (friendly nudge vs. formal notice). Emails go through Resend with open tracking, so users know if the client saw the reminder or if it bounced.
Time tracking with invoice linking
A built-in timer lets users track hours against specific clients and projects. At the end of a billing cycle, tracked time converts directly into invoice line items with one click. No more copying hours from a spreadsheet into an invoice tool.
Challenges
Handling currency conversions across payment gateways
Freelancers bill in different currencies depending on the client. Stripe and PayPal handle conversions differently, with different fee structures. Built a normalization layer that calculates the effective amount received after all fees and conversions, so the dashboard shows real revenue, not invoice totals.
PDF rendering consistency across browsers and email clients
Invoices need to look identical whether opened in Chrome, downloaded as PDF, or viewed in Outlook. Standardized on server-side Puppeteer rendering with a fixed viewport and embedded fonts. Every invoice generates a canonical PDF that gets attached to the email and stored for records.
Results
Billwise processes invoices for over 400 active freelancers, with a 94% on-time payment rate thanks to automated reminders.
400+
Active freelancers on the platform
94%
On-time payment rate
$2.1M
Total invoiced through the platform
Tech Stack
Leadership
- Defined the product roadmap and prioritized features based on user feedback from beta testers.
- Led a team of 2 developers, handling architecture decisions and code reviews.
- Designed the pricing model and payment flow that achieved 94% on-time payment rate.