# Technical design doc template

> A technical design doc template with context, approach, data model, alternatives, trade-offs, rollout and open questions. Copy it, or start it in Kanso.

The sections a design review needs, and none it does not.

Web page: https://kansohq.app/templates/technical-design

Updated: 5 October 2026

## The template

### Context

What exists today, and why it no longer fits.

### Approach

The design in a few sentences, then the detail below.

### Data model

```ts

```

### Alternatives considered

#### Option A

Why not.

#### Option B

Why not.

### Trade-offs we are accepting

-

### Rollout

1.

### Open questions

-

In Kanso, add a page and pick this template, or type / in any doc.

## How to fill it in

1. Say what exists today, and why it no longer fits.
2. Describe the approach, then the data.
3. Compare at least two alternatives.
4. Plan the rollout and the rollback.

## Questions

### What is a technical design doc?

A document written before significant engineering work that explains how it will be built, which alternatives were considered and what trade-offs are accepted.

### How long should a design doc be?

Two to five pages is typical. Put a summary first so a reader can stop early.

### Who should review a design doc?

The people who will build it, the people who will run it, and one person who is not close to the problem.

## Keep reading

- [How to write a technical design doc](https://kansohq.app/guides/how-to-write-a-technical-design-doc.md): A technical design doc explains how you will build something and why. Learn the sections to include, how to compare options and how to get a useful review.
- [Decision record template (ADR) to copy | Kanso](https://kansohq.app/templates/decision-record.md): An architecture decision record (ADR) template with the decision, status, context, consequences and revisit condition. Copy it, or start it in Kanso.
- [PRD template: a free product spec to copy | Kanso](https://kansohq.app/templates/product-spec.md): A free PRD template for software teams: problem, solution, who it is for, scope, success measure and open questions. Copy it, or start it in Kanso.
- [Feature spec template with acceptance criteria | Kanso](https://kansohq.app/templates/feature-spec.md): A feature spec template with how it behaves, acceptance criteria, edge cases and what you are not doing. Copy it, or start it as a page in Kanso.

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