Civil Billing & Engineering Workflow Automation

Engineering-grade billing automation for civil engineering firms

Role: System Designer & Developer
Context: Production Platform

Problem Statement

Civil engineering billing is structurally complex. Projects span months or years, involve multiple sub-scopes, and require progress billing that reflects contract terms, effort allocation, and phase-specific deliverables.

Most firms rely on manual workflows: exporting time entries from timekeeping systems, organizing them by project and sub-project in spreadsheets, calculating billing summaries, and cross-referencing contract terms before generating invoices. This process is time-intensive, error-prone, and difficult to audit.

QuickBooks Online—while widely used—lacks native engineering billing logic. Its progress invoicing features are limited, and QuickBooks Time integration does not automatically align time data with engineering contract structures. The result is a recurring administrative burden that creates bottlenecks during billing cycles.

Solution & Approach

The platform bridges QuickBooks Online and QuickBooks Time, applying engineering-specific logic to transform raw time data into structured, reviewable billing summaries.

Automated Time Retrieval
Retrieves time entries by project and sub-project, filtering by date range and team member. Handles QuickBooks Time API constraints and structures data for downstream processing.
Engineering-Specific Billing Summaries
Groups time data by contract scope, task type, and billing classification. Generates summaries aligned with engineering deliverables rather than generic timekeeping categories.
Progress Billing Logic
Calculates percent complete, remaining contract balances, and unbilled amounts based on user-defined contract structures and billing history. Works with projects lacking native QuickBooks progress fields.
Clean, Reviewable Reports
Formats billing summaries for internal engineering review before invoice generation. Ensures accuracy, prevents overbilling, and provides clear audit trails.
Optional Invoice Creation
Pushes validated summaries directly into QuickBooks Online as invoices, eliminating manual re-entry and reducing transcription errors.

The system prioritizes clarity and auditability over feature density. Every calculation is traceable, and every summary is designed to be reviewed by a person before becoming an invoice.

Technical Stack

Languages & Frameworks

TypeScript, Node.js, React, Next.js

APIs & Integrations

QuickBooks Online API, QuickBooks Time API, OAuth 2.0

Infrastructure

Vercel, PostgreSQL, secure token management

Development Approach

API-first design, structured data models, audit-focused architecture

Impact & Outcomes

The platform replaces hours of manual reconciliation with a repeatable, auditable workflow. Billing cycles that previously required extensive spreadsheet work now occur in minutes, with fewer errors and better documentation.

Engineering principals can review billing summaries in a clean, structured format before approving invoices. This improves accuracy, reduces billing disputes, and maintains the professional standard expected in client relationships.

What this demonstrates: Systems thinking applied to operational problems, API integration expertise, understanding of real-world accounting constraints, and the ability to design tools that solve specific professional pain points without over-engineering.

Skills Demonstrated

Engineering OperationsBilling AutomationAPI IntegrationQuickBooks DevelopmentSystems ArchitectureTypeScriptReact/Next.jsOAuth 2.0Database DesignProcess AutomationAudit Trail DesignDomain-Specific Logic

Links

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