Built for engineers

Stop losing decisions inSlack threads and Google Docs

DesignDoc gives every RFC a structured workflow, inline reviews, and a permanent searchable home — so your team never asks “why did we build it this way?” again.

Get Started

CLI + MCP + Web · Built for engineering teams

RFC-042: Credit System Redesign — designdoc.tech/orgs/acme

## Detailed Design

The new billing engine introduces two

core abstractions:

1. `BillingPlan` — defines pricing tiers

2. `UsageMeter` — tracks consumption

```mermaid

graph LR

A[User] --> B[BillingPlan]

B --> C[UsageMeter]

C --> D[Invoice]

```

MermaidKaTeXCode blocksTablesTask listsTemplates3 comments · 2 resolved

You've been here before

Design decisions happen everywhere — and disappear just as fast.

Lost in Slack

A critical architecture decision made in a thread. Two weeks later, nobody can find it. The new hire rebuilds the same thing differently.

Rotting in Google Docs

50 design docs in a shared drive. No workflow, no status. Half are drafts, half are abandoned. Which ones are actually approved?

Tribal knowledge

"Ask Sarah, she was here when we chose Kafka." But Sarah left. Now it's folklore — no written record of the trade-offs or context.

Features

Everything your RFC process needs

Not another wiki. A purpose-built tool for engineering decisions.

Structured Workflow

Every RFC moves through clear states — Draft, In Review, Accepted, Implementing, Done. Each transition is tracked with timestamps and actors.

Rich Markdown Editor

Split-pane editor with live preview. Mermaid diagrams, KaTeX math, syntax-highlighted code blocks, tables, and task lists built in.

Inline Comments & Reviews

Leave feedback on specific sections. Request reviews from teammates. Resolve threads as you iterate. Like code review, but for design docs.

Full-Text Search

"Why did we pick Postgres over MySQL?" One search, instant answer. Every decision findable in seconds — even years later.

AI-Native (MCP Server)

Claude, Cursor, and Copilot can query your decisions while writing code — so they follow your team's actual conventions, not generic patterns.

Public Portal

Share public RFCs externally, keep private ones locked. One clean URL your team always knows.

How It Works

From idea to permanent record

Three steps. Clear path. No decisions lost.

01

Write

Start from a structured template — summary, motivation, design, alternatives. The split-pane editor shows live Markdown preview as you type.

02

Review

Request reviews from teammates. They leave inline comments on specific sections. Iterate, resolve threads, and refine until the proposal is solid.

Resolved
03

Decide

Accept, reject, or send back for revision. Every transition is recorded with context — building your team's searchable decision history forever.

Accepted — Apr 1
In Review — Mar 28
Draft — Mar 25

Why not just use…?

General-purpose tools aren't built for structured decisions.

designdocGoogle DocsNotionConfluence
RFC workflow statesplugin
Inline section reviewsbasic
Decision audit trail
AI/MCP integration
CLI & MCP access

Built for every engineer in the room

Tech Leads

Write RFCs, get structured feedback, and drive decisions to completion without chasing approvals.

Eng Managers

See which decisions are pending, stale, or blocked. Know if your RFC process is actually working.

IC Developers

Understand why things were built a certain way. Search past decisions before starting implementation.

Solo Builders

Document decisions for your future self. Revisit a project in 3 months and know exactly why.

Your team's decisionsdeserve a real home.

Start documenting your team's decisions today.

CLI + MCP + Web · Built for engineering teams