---
id: con-compound-loop
schema: concept/1
layer: garden
status: emerging
name: Compounding loop
aka: ["compound engineering", "compound knowledge", "compound writing", "lessons learned file", "write it down for next time"]
summary: >
  After each piece of AI work, writing down what you learned where the AI will read it next time, such
  as a line in its instructions, a saved example or a new check, so you don't catch the same mistake twice.
  Named "compound engineering" by Kieran Klaassen at Every.
first_seen: "2025"
relations:
  builds_on: [con-custom-instructions, con-skills]
  evolved_from: []
  related: [con-memory, con-evals]
  parallels:
    - idea: "an after-action review"
      field: "military and project management"
      note: "After each operation the team asks what was supposed to happen, what did happen and what to do differently, and the answers change the next plan."
    - idea: "a kitchen's prep notes"
      field: "cooking"
      note: "A cook who burns the sauce once writes 'lower heat after the cream goes in' on the recipe card, so nobody burns it again."
implementations:
  - { provider: every, name: "Compound Engineering plugin", resource: res-other-every-compound-engineering-guide }
  - { provider: every, name: "Compound Knowledge plugin", resource: res-other-every-agent-that-saved-my-brain }
competencies: [cmp-make-it-repeatable, cmp-check-the-result]
origin:
  kind: ai-proposed
  by: "seed agent 2026-10-16"
  rationale: "Names the habit learners most often skip in make-it-repeatable: feeding each correction back into the AI's instructions so the next job starts better."
---

Most people fix an AI's mistake in the chat and move on. Next week the mistake comes back, because nothing the AI reads has changed. A compounding loop adds one step at the end of each job: decide what you learned, and put it somewhere the AI will see next time.

That place might be your custom instructions, a skill's checklist, a saved good example, or a short "things to avoid" note in a project. A useful test, from Every's compound engineering plugin: would someone repeat the mistake if this note disappeared? If not, it isn't worth saving.

Kieran Klaassen at Every named the idea for software work in 2025. Austin Tedesco, also at Every, applied it to office work, and Katie Parrott to writing.

## Example

A grants officer asks AI to draft funder reports. Twice it calls a programme "free" when it is low-cost. She adds one line to her project instructions: "Our programmes are low-cost, never free." The error stops, and the next report needs one fewer edit.

## How it connects

- Builds on **custom instructions** and **skills**, the places where lessons get saved.
- A saved check you run every time is a small **eval**.
- Differs from **memory**: you choose what gets written down and where.

## Try it

After your next AI task, write one sentence about what you corrected. Add it to your instructions or project, then run the same kind of task again and see whether the correction held.