Notes on building.
Guides on mobile apps, web platforms and AI products. Cost breakdowns, stack comparisons and how we ship.
Stripe Billing V2 vs Lago vs Orb: Usage-Based Billing in 2026
Three platforms dominate usage-based billing in 2026, but they solve different problems. Here is an honest breakdown of Stripe Billing V2, Lago, and Orb so you can pick the right engine for your metering and invoicing needs.
Technology · Jul 1, 2026 · 14 min read
Context Windows vs RAG vs Fine-Tuning: When to Use Each
With 1M+ token context windows now available from Claude and Gemini, the old playbook for giving LLMs domain knowledge has changed. But long context is not always the right answer. Here is a practical decision framework covering cost, latency, accuracy, and the hybrid approaches that actually work in production.
Technology · Jul 1, 2026 · 15 min read
AI Copilot for SaaS Products: Architecture and Strategy Guide
Adding an AI copilot to your SaaS product is no longer optional. This guide covers the full spectrum from architecture and UX patterns to pricing strategy and competitive moat, with real examples from Notion AI, Linear, and Intercom Fin.
Technology · Jul 1, 2026 · 14 min read
How to Build a Spa and Wellness Booking App With AI Scheduling
Spa owners lose thousands every month to scheduling gaps, underbooked therapists, and rooms sitting empty between treatments. Here is how to build a booking app that uses AI to fill every hour and keep clients coming back.
How to build · Jun 30, 2026 · 14 min read
How to Build a Tutoring and Online Learning Marketplace App
Two-sided education marketplaces are booming, but most fail because they ignore the hard problems: tutor verification, real-time video, timezone scheduling, and the cold start. Here is how to build one that actually works.
How to build · Jun 30, 2026 · 15 min read
How to Build an AI Copilot for Your SaaS Product in 2026
Your users do not want another chatbot. They want an AI copilot that understands their data, takes actions inside your app, and saves them hours every week. Here is how to build one in 6 to 12 weeks.
How to build · Jun 30, 2026 · 15 min read
How to Build a Patient Engagement and Communication Platform
Patient engagement platforms sit at the intersection of clinical workflows and consumer expectations. This guide covers how to build one from scratch, including secure messaging, automated reminders, intake forms, care plan tracking, and deep EHR integration, all while staying on the right side of HIPAA.
How to build · Jun 30, 2026 · 14 min read
How to Build an AI Field Inspection App for Property and Safety
Field inspectors still fight with clipboards, poor connectivity, and hours of manual report writing. Here is how to build an AI-powered inspection app that works offline, detects hazards with computer vision, and generates polished reports automatically.
How to build · Jun 30, 2026 · 14 min read
How Much Does It Cost to Build a Tutoring Marketplace in 2026?
From tutor vetting and WebRTC video calls to AI-powered matching and payment splits, here is what every tutoring marketplace feature actually costs to build in 2026.
Cost & planning · Jun 29, 2026 · 13 min read
Cursor Rules vs CLAUDE.md vs Codex Instructions: AI Dev Config
Every AI coding tool now supports project-level configuration files that shape how the agent writes code. Here is how .cursorrules, CLAUDE.md, and Codex instructions compare, and how to set them up for consistent, high-quality output across your team.
Technology · Jun 29, 2026 · 14 min read
How Much Does It Cost to Build a Spa and Wellness Booking App?
Spas and wellness centers have outgrown generic booking tools. Here is what it actually costs to build a custom spa booking app with therapist scheduling, room management, and loyalty programs.
Cost & planning · Jun 29, 2026 · 13 min read
How Much Does It Cost to Build an AI Sales Agent Platform?
AI sales agent platforms like 11x.ai and Artisan are charging $2,000 to $10,000 per month per seat, and companies are paying because the ROI is obvious. If you want to build your own, expect to invest $50,000 for a basic MVP up to $450,000+ for a full enterprise platform with voice, multi-channel outreach, and personalization engines. This guide breaks down every cost layer so you can plan accurately.
Cost & planning · Jun 29, 2026 · 14 min read