Contract Lens

A deployed multi-tenant SaaS where an LLM extraction pipeline turns PDF and DOCX contracts into typed, structured data that drives a deadline and alert system.

Role — Sole engineer — full-stack product, from the multi-tenant data model to the AI extraction pipeline.

Next.js

React

TypeScript

Prisma

PostgreSQL

Tailwind CSS

Vercel AI SDK

GPT-4o-mini

DeepSeek R1

Highlights

Versioned prompt configs with two-model routing by task shape — GPT-4o-mini for cheap classification and routing, DeepSeek R1 for reasoning-heavy extraction — streamed live to a 4-step upload wizard.

Multi-tenant data model with 5 roles (owner to viewer) and permission checks that scope every contract, task, and alert query to the caller's organization.

AES-256-GCM encryption at rest for sensitive contract fields (summary, conditions, and the stored file itself).

Deadline-alert and task system with email invitations, on a bilingual (DE/EN) landing page.

Overview

Contract Lens is a deployed SaaS that helps small German law firms manage contracts with AI assistance. Uploaded PDFs and DOCX files run through an extraction pipeline — a classifier routes the document to a type-specific extractor whose output is schema-validated — surfacing structured data in a contract editor alongside deadline alerts, role-based multi-tenancy, and encryption at rest for sensitive fields.

The product thesis is an AI that extracts rather than chats: no prompting required from the user. Prompt configurations are versioned in the repository so extraction changes stay traceable, and routing runs through the AI Gateway, which makes the model choice a string rather than an application-code dependency.