Ship the client tools your practice needs — without the spreadsheet workarounds
Tax season is stressful enough without debugging a client portal at 11pm. You have tried building document upload systems, deadline trackers, and reporting dashboards with AI tools — and they almost work, until file uploads silently fail or your QuickBooks connection drops mid-sync. We finish your tools so you can focus on the numbers, not the code.
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“My client portal lets people upload tax documents but half the files disappear — no error message, just gone.”
AI-generated file upload code often has silent failure modes — file size limits without warnings, unsupported MIME types rejected without feedback, or uploads that timeout on slow connections and never retry. We fix the upload pipeline with proper validation, progress indicators, chunked uploads for large files, and confirmation receipts so neither you nor your client ever wonders if a document actually arrived.
“I built a tax deadline tracker but it shows the wrong filing dates for S-corps and partnerships.”
AI tools generate plausible-looking deadline logic but confuse entity types, ignore extension dates, and miss state-level variations. A tracker that shows March 15 for a sole proprietor or April 15 for a partnership extension erodes client trust fast. We implement correct deadline rules per entity type, with extension logic and state-specific overrides.
“My QuickBooks integration pulled data once but now it just returns authentication errors every morning.”
OAuth token refresh is the single most common failure in AI-generated integrations. The initial connection works, but tokens expire after an hour and the generated code never handles the refresh flow. We implement proper token management with automatic refresh, retry logic, and alerts when re-authorization is genuinely needed.
“I made a P&L dashboard for clients but the numbers do not match what is in their actual books.”
Financial reporting code generated by AI often mishandles accrual vs. cash basis, double-counts journal entries, or ignores voided transactions. A dashboard that shows the wrong net income is worse than no dashboard at all. We reconcile the data logic against your accounting method so the numbers tie out to the penny.
What that looks like
A client portal where businesses upload receipts, bank statements, and tax forms into organized folders per tax year
The folder structure creates duplicate directories for clients with special characters in their business name, drag-and-drop upload does not work on Safari, and there is no notification when a client uploads a new document.
A custom reporting dashboard that pulls QuickBooks Online data and displays monthly revenue, expenses, and cash flow trends
The QuickBooks API connection breaks every 60 minutes due to expired tokens, the revenue chart double-counts refunded invoices, and switching between cash and accrual basis shows identical numbers because the filter is not actually wired to the query.
A tax deadline calendar that tracks filing dates, extension deadlines, and estimated payment due dates for every client entity
The calendar displays all deadlines in January regardless of actual due date because the date parsing assumes DD/MM/YYYY format, entity type filtering does not work, and there is no way to mark a filing as completed.
What I handle
The work that AI tools start but can't finish.
Fixed pricing
Most accountants projects fit the Feature €199. No custom quotes, no surprises.
Connect a payment provider, third-party API, or external service to your existing app.
Add a complete feature — authentication, database, dashboards, or user-facing functionality.
End-to-end build of a small product — from AI-generated starting point to production-ready.
ArjanCodes
Questions accountants ask
Can you integrate with QuickBooks Online and Xero, or just one?
We work with both. QuickBooks Online and Xero have different API structures, but we handle the authentication, data mapping, and sync logic for either platform. If you need to support both because different clients use different systems, we can build a unified dashboard that pulls from whichever source each client uses.
My clients upload sensitive financial documents — how do you handle that data?
We work exclusively in your repository and infrastructure. Client documents never pass through our systems. We implement encryption at rest and in transit, access controls per client, and audit logging so you have a clear record of who accessed what and when.
I need the numbers to be exact — can I trust AI-finished code for financial calculations?
That is exactly why we exist. AI generates plausible financial logic that is often subtly wrong — rounding errors, off-by-one in date ranges, mishandled negative values. We test every calculation path against known correct figures and edge cases so the output matches your books, not an approximation of them.
Tax rules change every year — will the tool break next filing season?
We build deadline and calculation logic in a configurable way — tax years, rate tables, and filing dates are stored as editable data, not hardcoded. When rules change, you or we can update a simple configuration file instead of rewriting code. We also flag anything jurisdiction-specific so you know exactly what to review each year.
Tell me what you built
No commitment, no jargon. Just describe what you have and what you need. I'll tell you exactly what it takes to ship it.
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