Development of DocFlow E-signature Platform

Client: Confidential

Role: Lead Web App Developer & Automation Engineer

Scope: Full-Stack Engineering · Digital Signature Logic · Security Architecture

Tools: Node.js, PostgreSQL, React, Redux Toolkit, Sequelize ORM, Reedux Toolkit, Express, React Router, Sequelize, JWT, Passport.js, Multer, Bcrypt, Nodemailer, PDF-lib, React PDF Viewer, Tailwind CSS, Sweet Alert2, Axios, OTPlib, QRCode, Vite

Project Link: https://portfolio.inafana.com/project/15

DocFlow is an enterprise-grade electronic signature platform designed to eliminate the friction of physical document handling. The system provides a complete digital lifecycle for document management, allowing users to transform static PDFs into interactive templates with precise field placement, automated recipient workflows, and legally-binding digital signatures.

Developing a secure, compliant e-signature platform requires more than just a "drawing" tool; it necessitates a robust backend to handle complex document states. Key challenges included:

Dynamic PDF Manipulation: Engineering a visual editor that maps coordinate-based signature fields onto PDF layers.

Workflow Automation: Managing multi-recipient signing sequences (parallel vs. sequential) with real-time status triggers.

Ironclad Security: Implementing multi-factor authentication (MFA) and immutable audit trails to ensure document integrity.

High-Volume Management: Architecting a template system that could scale across thousands of users without performance degradation.

As the Lead Developer and Automation Engineer, I focused on building a high-reliability infrastructure:

Interactive PDF Engine: Developed a React-based visual designer that allows users to drag-and-drop signature, date, and text fields with pixel-perfect precision, which are then flattened into the final PDF.

Automated Document Lifecycle: Architected a state machine to track documents from Draft → Sent → Completed, with automated email triggers and reminder pings to recipients.

Advanced Security Protocols: Integrated JWT-based session management, bcrypt hashing, and a dual-layer MFA system supporting both Email OTP and Google Authenticator (TOTP).

Relational Data Integrity: Designed a complex PostgreSQL schema via Sequelize to manage the relationships between templates, documents, multi-role recipients, and activity logs.

Compliance & Audit Logging: Engineered a comprehensive system-wide audit trail that captures every user action, timestamp, and IP address to ensure accountability for every signature.

Delivered a seamless, "zero-print" solution that significantly accelerated document turnaround times for enterprise clients. The platform successfully supports complex multi-user workflows with 100% document visibility and high-tier security compliance. By automating the follow-up and notification process, DocFlow reduced the manual effort involved in contract management by over 70%.