Field guide
The Product Around the Model
A product-engineering field guide for AI-integrated applications.
Jubayer Hossain
Product engineering
The Product Around the Model
A product-engineering field guide for AI-integrated applications.
How to architect any full-stack product around AI — stack choices, trust boundaries, and a build order that does not bet the product on the model.
Inside the book
Chapter titles and one-line blurbs are public. The body unlocks after email.
- 01
The product owns the work
Your application is the system of record. The model is a vendor. If the integration is slow or down, business state still stands.
- 02
Scope and trust boundaries
Draw who talks to whom before you pick a framework. The browser never holds AI credentials. Authorization lives in your API.
- 03
Stack choices that survive production
How to pick a client, one API, identity, and a database from the job the product has — not from a copied template.
- 04
Cost forks, not brand loyalty
Same schema, same code: compare managed versus self-operated. Pay a vendor only when it buys a capability you actually need.
- 05
One workflow engine
Tenancy from day one. Roles as capabilities. One parameterized state machine instead of a new workflow per screen.
- 06
AI as a versioned contract
Your API proxies streamed chat and long jobs. Persist first. Send opaque ids to the model — never emails, never the browser.
- 07
Letting outsiders in
When someone should participate without a full account: a shareable URL is a capability, not a login. Verify before writes.
- 08
Plugins, ops, and ship order
Billing, mail, and files as ports. Build in dependency order. Write the decisions down for your product, not a copied checklist.
Who it's for
- Founders shipping an AI-integrated web, mobile, or mixed product
- Engineers who need the application to stay the system of record
- Teams choosing a stack before the first production incident, not after
Who it isn't
- People looking for a weekend ChatGPT wrapper tutorial
- Teams that want the model to own identity, billing, or publish rights
- Anyone expecting a copy of a client architecture or a named vendor contract
Jubayer Hossain
Full Stack Engineer — I write the architecture, then I ship it.
FAQ
Why do you need my email?+
It is how you unlock the book, and how I know someone actually wanted it. I may follow up about project work. I do not sell addresses.
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Can I share a chapter link with a colleague?+
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Is this a PDF I can download?+
No. It is an on-site ebook reader. That keeps the layout readable and the chapters off public crawls.
Do I need a password or a secret you send me?+
No. Public visitors unlock with email only. Nothing is mailed to you except if you later book a call.