Our Sydney AI SaaS projects cover product design, AI architecture, development, and go-to-market. Product design (weeks 1-2): defining the AI SaaS product. We define: the AI value proposition (what does the AI do that creates measurable value for the customer? Not "we use AI" but "we reduce contract review time by 70% using AI" — specific, measurable, and compelling), user workflows (how do users interact with the AI? Is the AI autonomous (processing data without user intervention), assistive (providing suggestions that users accept or modify), or interactive (conversational interface)?), pricing model (how do you charge for AI? Per-user (traditional SaaS — simple but doesn't align with AI cost), per-usage (charging per document processed, per query answered — aligns with cost but harder for customers to predict), tiered (bundles of AI usage at fixed prices — balancing predictability with cost alignment)), and success metrics (how do you measure if the AI product is delivering value? Accuracy metrics, time savings, error reduction, customer satisfaction — defined before development so they can be built into the product). AI architecture (weeks 2-3): designing the technical foundation. Multi-tenant AI isolation: each customer's data completely separated — separate vector namespaces (each customer's knowledge base in its own Pinecone namespace or Weaviate tenant), tenant-scoped prompts (system prompts including tenant-specific context and constraints), conversation isolation (each customer's conversation history stored and retrieved separately), and audit logging (every AI interaction logged with tenant ID, input, output, and model used — for compliance and debugging). Model selection: choosing the right AI model for each feature — GPT-4o for complex reasoning and content generation, GPT-4o-mini for simple classification and extraction (15x cheaper), Claude for long document analysis, and on-device or self-hosted models for privacy-sensitive features. Cost architecture: designing the AI cost structure — estimating per-user AI cost (how many AI calls per user per month? What's the average token count per call? What's the model cost?), building cost monitoring (tracking AI cost per tenant, per feature, per model — enabling cost optimization), and implementing cost controls (rate limiting, model tiering, caching — preventing runaway AI costs from destroying margins). Development (weeks 3-10): building the AI SaaS product. Core platform: multi-tenant SaaS architecture — Next.js (React frontend), Node.js or Python (API layer), PostgreSQL (relational data — users, tenants, subscriptions, billing), and Redis (caching, rate limiting, session management). Authentication: Clerk or Auth0 — multi-tenant authentication with organisation management, SSO for enterprise customers, and role-based access control. AI layer: LLM integration (OpenAI API, Anthropic API — with abstraction layer enabling model switching without application changes), RAG pipeline (document ingestion → chunking → embedding → vector storage → retrieval → generation — the standard RAG architecture optimised for multi-tenant isolation), prompt management (versioned prompts stored in configuration — enabling A/B testing, prompt improvements, and per-tenant customisation without code deployment), and streaming responses (Server-Sent Events — streaming LLM responses to the frontend as they're generated, reducing perceived latency from 3-5 seconds to near-instant first token). Billing: Stripe Billing with usage-based components — subscription base (monthly platform fee) plus usage metering (AI calls, documents processed, queries answered — tracked per tenant and reported to Stripe for billing). Evaluation and monitoring (ongoing): measuring AI quality. We implement: automated evaluation (running test sets through the AI pipeline and measuring accuracy against known-good answers — regression testing for AI quality), user feedback (thumbs up/down on AI outputs — collecting signal about which responses users find helpful and which they don't), quality dashboards (accuracy trends, error rates, latency, cost — per feature and per tenant), and continuous improvement (using feedback data to refine prompts, update knowledge bases, and improve retrieval — the AI getting better over time based on real usage data).