Your stack does that.

Your stack, defined

Five parts. No store.

The word gets dressed up. It is not complicated. Your stack has five parts, and when you need something new, one of the last three grows.

1. One intelligence
Yours. Direct from a frontier company, on your bill, on your team and nobody else's. Claude, ChatGPT, Gemini, and the others are all frontier stacks. Pick one. Pay it directly. Do not go through a reseller, a platform, or a company plan if you can avoid it, because the things that make it yours ship there first and sometimes only.
Example: a single paid account, on your own card, that you open on your own laptop and phone.
2. Memory
What it knows about you, carried from one day to the next, so you never start over. Your preferences, your people, your projects, the way you like a thing done. Memory is what makes the difference between a tool and something that is on your side.
Example: you told it once that your daughter's school runs on a Tuesday-Thursday rotation. Three months later it moves a meeting without being told why.
3. Connectors
The doors into your records. Your mail, your calendar, your files, your messages, your bank, your photos, and the records of the companies you deal with. A connector does not copy the record. It lets the intelligence read it, and where you allow, change it. The open standard for this is called MCP; you do not need to know that, but your stack does.
Example: a connector to your calendar and your mail, so a message that says "can we move Thursday" gets answered with the meeting actually moved.
4. Skills
Ways of doing things it has learned once and can do again. A skill is what an app used to be, minus the store, the account, and the bill. A skill is usually a plain file: here is how I want my invoices written, here is how I check a draft before it goes out, here is the checklist for closing the shop.
Example: a file that says how you like your writing checked. It runs on everything you send, and it never asks you to upgrade.
5. Scheduled tasks
The part that makes it ambient. Things that run at five in the morning, or on a trigger, on your behalf, whether or not you remember them. This is what the phrase ambient intelligence means in practice: invisible, always on, never prompted. The plain-terms name is scheduled tasks. You do not know it is working because it is talking to you. You know because the work is done.
Example: every morning at 5:10, read what came in overnight, answer the four with obvious answers, and leave a two-paragraph note. You read the note in ninety seconds.

What a stack is not

Not an app
An app is a capability with a store, an account, and a bill attached. A stack is one relationship that absorbs capabilities. If you find yourself downloading something and making an account to get a capability your stack could learn, you have gone back to the store.
Not a wrapper
A wrapper is a model plus a prompt plus a login plus a monthly price. Its entire value can be reproduced as a skill file. It is a feature with a burn rate, and it holds leverage over you that a file does not.
Not a reseller
A reseller sells you someone else's intelligence with terms added. You get the models, late, and none of the things that live in the source's own app. You did not buy intelligence. You bought a subscription to someone else's decisions about it.
Not a portal
A portal is a place you are supposed to go. A branded assistant with a company's logo on it is a portal. Your stack does not go to portals. It reads records, under the record-holder's rules, and moves on.

What is still true today

All five parts exist in the frontier stacks today. Some are rough. Scheduled tasks fail sometimes and need to be checked. Many connectors do not exist yet, especially for banks, schools, and small vendors, and some that exist go through a third party that is itself a company with terms. Memory is uneven. None of that changes the shape of the thing. It changes how much setup an entry on the Does list needs, and every entry says.