AI SaaS Platform with Multi-User Accounts and Payments
Marcel Stredak
Prompt Kitchen: Production-Grade AI SaaS & Monetization Engine
The Mission
Transforming casual AI interactions into a professional, scalable productivity asset.
Most users struggle with Prompt Debt. This is a mess of unorganized, low-quality inputs scattered across browser tabs. I architected Prompt Kitchen from a blank canvas to solve this. It is a "GitHub for Prompts" that allows power users to organize and optimize their AI workflows.
The Strategy: Architecture for Profitability
As the Lead Architect, my focus was on the business guardrails that keep a SaaS profitable. I ensured every token and tier is managed with precision.
Monetization and Gating Logic
Tiered Subscription Ecosystem: I engineered a robust billing system using Stripe and PayPal. It features automated webhooks to manage Free vs. Pro tiers with 100% reliability.
Feature Gating Middleware: I implemented advanced server-side checks to ensure premium features, like the optimization pipeline, are only accessible to paying users.
Data Sovereignty: I designed a custom NextAuth v5 layer to ensure multi-user data isolation. This is crucial for enterprise-level security.
The Optimization Pipeline
Chain-of-Thought Refinement: I integrated a custom pipeline via OpenAI that transforms vague inputs into high-performance instructions automatically.
Workflow Acceleration: I optimized the frontend for high-speed interaction with instant fuzzy search and one-click "Never Write Twice" functionality to eliminate repetitive tasks.
A SaaS is only as good as its margins. I built the tracking tools to ensure every OpenAI token used is accounted for. This protects the platform's bottom line from day one.
Technical Architecture
Frontend: Next.js 16.1.6, React 19.2.3, and TypeScript.
Database: PostgreSQL architected for secure multi-user data isolation.
State and Motion: Framer Motion and Shadcn/ui for a premium, responsive feel.
Admin Suite: A dedicated dashboard for token tracking, rate limiting via Upstash and Redis, and real-time DAU analytics.
The Outcome
I delivered a production-ready platform that handles the entire prompt lifecycle from initial draft to cost-controlled optimization.
100% Automated Tier Gating: Zero manual intervention required for upgrades.
Real-Time Cost Auditing: Granular token tracking per user to prevent API abuse.
Sub-Second Responsiveness: Optimized database queries and frontend state management.
Integrated Prompt Engineering Workspace
Categorized Prompt Library and Organization
Operational Analytics and Resource Monitoring
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Posted Mar 22, 2026
I architected a full-cycle AI SaaS from a blank canvas. It features tiered monetization, automated prompt optimization, and granular cost controls.
