Other | Austria
Unified Authentication and Billing Platform for AI Products Austria
A centralized authentication and billing platform that enables AI products to share user access, manage subscriptions, and support flexible usage-based pricing through a single integration.
Simplifying Authentication and Billing for AI Products
Solution
MVP, SaaS
Duration
4 months
Team
1 X Backend Developer, 1 X Frontend Developer, 1 X Project Manager, 1 X QA
Engagement Model
Time & Material
As AI-powered products continue to emerge across industries, development teams often face the same recurring challenges: implementing secure authentication, managing subscriptions, and supporting increasingly complex usage-based billing models. Rebuilding this infrastructure for every new application slows product delivery and diverts attention from innovation.
To address these challenges, we developed a centralized authentication and billing platform that serves as the foundation for multiple AI applications. Acting as a unified provider, the platform enables products to share authentication, user management, and billing capabilities through a single integration.
The solution combines centralized user authentication, flexible subscription management, wallet-based payments, and real-time usage tracking into one scalable platform. By integrating with Lago and exposing a developer-friendly SDK, new AI products can quickly implement secure access control and consumption-based billing without building custom infrastructure from scratch.
The result is a scalable ecosystem that accelerates product development, simplifies administration, and delivers a consistent experience for both developers and end users.
Built with
Key highlights
Centralized Authentication
Flexible Usage-Based Billing
Developer-Friendly SDK
Real-Time Credit & Usage Management
The Challenge
As Extensity's portfolio of AI applications continued to grow, building and maintaining separate authentication and billing systems for each product became increasingly inefficient. Development teams were repeatedly implementing the same core infrastructure instead of focusing on delivering new features and accelerating product development.
At the same time, traditional billing platforms were not designed to support the flexible monetization models required by AI applications. Managing subscriptions alongside usage-based pricing, token consumption, prepaid wallets, and real-time quota validation introduced significant complexity for both administrators and developers.
The objective was to create a centralized platform that would eliminate duplicated effort, provide a consistent authentication experience across multiple applications, and simplify the implementation of flexible billing models while remaining scalable as new AI products were introduced.
The Solution
We developed a centralized authentication and billing platform that serves as the foundation for Extensity's AI ecosystem. Acting as a unified provider, the platform enables multiple applications to share authentication, authorization, and billing capabilities through a single integration, providing a consistent experience for both administrators and end users.
To simplify monetization, the solution integrates with Lago while abstracting its complexity through reusable billing templates. This allows administrators to configure subscription plans, wallet-based payments, and usage-based pricing without rebuilding billing logic for every new product. At the same time, a developer-friendly SDK enables product teams to integrate authentication, permission validation, quota management, and consumption tracking using straightforward API calls, significantly reducing implementation effort.
By centralizing user management, billing, and usage tracking, the platform provides a scalable foundation that allows development teams to launch new AI applications faster while ensuring secure access control, accurate consumption reporting, and flexible pricing across the entire product ecosystem.
Main features
Admin Panel
A dashboard that allows to manage the content and actors of the app
Payment Integration
Seamless electronic payments for effortless transactions.
Advanced Search
Enhanced search for precise results.
User Registration
An easy way to create frontend user registration form and login form
User Roles
Defines permissions for a group of users to perform a certain set of tasks
Our partner's thoughts
We brought Webamboos in to build the billing infrastructure for our AI platform — a usage-metering layer over Stripe, in the spirit of Lago. The brief wasn't trivial: subscription plans, token tracking, and credit-based metering where a credit budget maps to feature tiers (a pool of credits buys either a handful of high-quality deep-research runs or many lighter ones). They delivered the whole thing — hosting setup on our side, plan configuration, the metering logic — without us having to babysit it. What stood out wasn't just the output, it was how they worked. The CTO came to every meeting prepared. When he didn't have an answer on the spot, he didn't improvise — he went away, did the research, and came back with something thorough and complete. Rarer than it should be. The cadence suited us perfectly. I don't enjoy meetings that circle a decision for an hour, and I never had to: one focused hour a week, run as proper sprints, genuinely agile. The loop was clean — they'd ask for what they needed, I'd give direction, they'd dig into the requirements, return with analysis and recommendations, and I'd decide. No churn. Kind people, well organized, and the work shipped smoothly start to finish. Would work with them again.
Claudiu Leoveanu-Condrei
CTO at ExtensityAI
