Andrej Karpathy's One-Text-Note System, Built Into an App

In March 2025, Andrej Karpathy posted on X about the note-taking system he had been quietly using for years. He calls it the append-and-review note. One single text note in Apple Notes, named "notes." Anything that comes to mind gets appended to the top. Every once in a while he scrolls down through the older stuff and rescues anything that still deserves attention by copy-pasting it back up. Things that don't get rescued sink, slowly, "almost as if under gravity."

What's striking about reading it, if you've used notetime for a while, is how exactly the two systems describe the same thing. The mechanic Karpathy built by hand in a generic notes app is the mechanic notetime is built around natively. The structure has a name in the cluster of posts that follow this one: append-only journaling. This article walks through the overlap, and then the one place where notetime does something different on purpose.

Karpathy's System, Reduced to Three Rules

Strip the post to its load-bearing parts and there are three rules.

One Note, Not a Tree

Karpathy keeps a single text note. No folders, no sub-notes, no tagging system, no graph view. He gives a specific reason: "Maintaining more than one note and managing and sorting them into folders and recursive substructures costs way too much cognitive bloat. A single note means CTRL+F is simple and trivial."

This is the part most note-taking advice gets wrong. The internet is full of Notion/Obsidian setups that try to solve "where do I put this thought" by adding more places to put it. Karpathy's answer is to delete the question.

Append to the Top, Without Metadata

Anything that comes to mind gets pasted at the top. No date, no project tag, no concept link. The exception is a tiny set of inline tags he uses for things he wants to revisit by category — watch: for movies, listen: for podcasts, read: for books — because they make CTRL+F faster.

That's the whole capture loop. Idea arrives, gets typed at the top, you move on. He's explicit about why: "When I note something down, I feel that I can immediately move on, wipe my working memory, and focus fully on something else." The no-metadata posture isn't aesthetic; for the principled case for time as the organizing axis, the timestamp is the only piece of metadata that pays for itself, and Karpathy's setup approximates the same conclusion by hand.

Review by Drift, Promote by Hand

Time does most of the sorting. New stuff lands on top, so older entries slide down the page. Periodically he scrolls through the bottom and skims. Anything that still deserves attention gets copy-pasted to the top again. Anything that no longer matters stays where it is and keeps sinking.

Notes that genuinely fade away are not deleted. They just stop being on top. Notes that keep mattering keep getting rescued, and over years they end up being the things you've actually thought about most. For the canonical version of this practice on a fixed cadence, see the two-week note review ritual.

Where notetime Maps One-to-One

A notetime "diary" is, structurally, exactly the Karpathy note. One linear surface, infinite append, full-text search across everything. The same three rules show up, but a couple of them are no longer rules — they're the default.

One Diary Replaces "One Note"

The unit of organization in notetime is the diary, and most users have just a few — work, personal, a project log. Each one is a single append-only stream. There are no folders, no sub-pages, no nested anything. If you wanted to run Karpathy's setup literally, you'd open one diary called "notes" and never make another, and the app would behave correctly.

The cognitive bloat Karpathy describes — folders, tags, structure, recursive substructures — isn't something you have to resist in notetime. It isn't there. The path of least resistance is already the system he's recommending.

The Timestamp Replaces "Append to the Top"

This is the part that maps the cleanest, with the smallest difference.

In Karpathy's setup, you manually type new things at the top so they're easy to find later. The position on the page is the proxy for when did I write this. New things are at the top because they were written most recently.

notetime makes that proxy explicit. Every line you write is auto-tagged with the exact time it was written. You don't manually decide where new things go — the timestamp is there from the moment you start typing, and the order is chronological by definition. The "no metadata" rule Karpathy enforces by hand becomes a thing you can't violate even if you tried.

The one inversion: notetime puts the newest entry at the bottom, like a chat or a paper journal, not the top. The direction is reversed but the property is identical — newest is closest to "now," oldest is furthest, and time is the only sort key.

Inline Tags Still Work, And Search Is Better

Karpathy's watch: / listen: / read: trick survives in notetime untouched. You can type watch: in front of any line and CTRL+F (or the in-app search) finds it later. There is no taxonomy to maintain, no schema to define — the tag is just text you happen to have written.

Where notetime does a little more is on the search side. CTRL+F across one giant Apple Notes page is fine until the page is a few years old and the same word appears six hundred times. notetime's search is scoped to a diary and ranked by recency, so the recent mention of "watch:" surfaces first, which is usually what you wanted.

Where notetime Goes One Step Different

There's one place the systems honestly diverge, and it's the part of Karpathy's post that is the most manual: the rescue.

In his setup, the way an old idea earns another round of attention is that you scroll down, find it, and copy-paste it back to the top. The act of re-typing or re-pasting is the promotion. Without that manual step, the idea keeps sinking and eventually drifts out of mind.

notetime doesn't have a rescue step, and on purpose. The review is the scroll. You scrub backwards through the timestamped log and read what you wrote three weeks ago, six months ago, last year. If something still matters, you don't have to copy-paste it forward — you just write a new line about it now, at the current timestamp, and it joins the top of the log on its own. The old entry stays where it is, in its real chronological place, and the new entry preserves the fact that you came back to this thought on this date. Over time, the diary records not just what you thought but when you thought it, and how often you returned.

The trade-off is honest. Karpathy's version keeps the most-thought-about ideas physically near the top of the page, which is great for at-a-glance recall. notetime trades that for an unbroken chronological record, which is better when you care about when something happened or want to reconstruct the timeline later. For a trader logging the tape, an engineer debugging an incident, or anyone keeping a journal, the timeline usually wins.