Notes on building.
Guides on mobile apps, web platforms and AI products. Cost breakdowns, stack comparisons and how we ship.
Self-Hosted LLMs vs API: When to Deploy Llama or Mistral in 2026
Llama and Mistral have closed the gap with GPT-4. Self-hosting can cut LLM costs 70-90% at scale, but only if you can amortize the engineering work. Here is the honest decision framework.
AI & strategy · Mar 6, 2026 · 13 min read
How to Build an AI Red Team: Adversarial Testing for LLM Apps
Every public LLM app gets jailbroken within days of launch. The teams that survive have an internal red team that finds the holes first. Here is how to build one without hiring 12 security engineers.
AI & strategy · Mar 6, 2026 · 12 min read
Svelte 5 Runes: A Founder's Guide to the New Reactivity Model
Svelte 5 threw out the reactive assignment model and replaced it with runes. Here's what that means for your product, your team, and your bet on the framework.
Technology · Mar 5, 2026 · 12 min read
TanStack Start vs Next.js: A New SSR Contender for 2026
Next.js has dominated React SSR for years, but TanStack Start is the first framework that feels like a genuine rethink. Here is how they actually compare in 2026.
Technology · Mar 5, 2026 · 13 min read
How to Run LLM Evaluations: A Practical Guide for Founders in 2026
If you ship an LLM feature without evals, you are flying blind. Here is the practical playbook we use to measure, regress, and actually improve production AI systems.
AI & strategy · Mar 5, 2026 · 13 min read
How Much Does It Cost to Build an AI Copilot for Your SaaS Product?
Every SaaS pitch deck in 2026 has the words 'AI copilot' on slide 4. Most of them have no idea what it actually costs. Here is the real breakdown, from 3-week chat wrapper to 6-month agentic assistant.
Cost & planning · Mar 5, 2026 · 13 min read
How Much Does It Cost to Build a Hotel Management System in 2026?
A hotel management system is not one product. It is a PMS, a channel manager, a payment gateway, a POS, and a reporting engine fused into one interface. Here is what building that actually costs.
Cost & planning · Mar 5, 2026 · 13 min read
How to Build a Language Learning App Like Duolingo in 2026
Duolingo made language learning look simple. It is not. Here is the real technical blueprint for shipping a language app people use longer than a weekend, from curriculum to FSRS to AI voice conversation.
How to build · Mar 5, 2026 · 14 min read
How to Build a Hotel Property Management System (PMS) in 2026
A hotel PMS is not one product, it is five products pretending to be one: reservations, front desk, channel manager, payments, and POS. Here is the technical blueprint for building one that independent hotels will actually buy.
How to build · Mar 5, 2026 · 14 min read
How to Build a Car Rental and Vehicle Sharing App in 2026
Turo and Getaround made peer-to-peer car rental look like a marketplace. It is actually an insurance product wrapped in a logistics product wrapped in an IoT product. Here is what it takes to build one.
How to build · Mar 5, 2026 · 13 min read
How to Build a Franchise Management Platform in 2026
Franchise software sits on top of the thorniest SaaS problem: one product with two distinct users (franchisor and franchisee) whose interests conflict. Here is how to build a platform both sides actually use.
How to build · Mar 5, 2026 · 12 min read
How to Build a Habit Tracking and Behavior Change App in 2026
Habit apps are easy to build and impossible to get right. The code is trivial. The behavior science is not. Here is how to build one that actually changes what users do.
How to build · Mar 5, 2026 · 12 min read