In development. First tracked test: Nov 17.

See which post broughtyour real signups.

An open-source tag and SDK. Add it with one prompt to Claude Code or Codex, and every visit and signup is traced back to the post, channel and campaign that sent it.

[ 01 / 05 ] how it works

Planned setup

One prompt to install. One call to read results.

Names and commands may change before release.

[ prompt ]

# paste into Claude Code or Codex
Add the GrowthRouter tag to every page of this site.

# or add it yourself
<script src="https://app.growthrouter.dev/t.js"
        data-site="umless" defer></script>

# one tracked link per post
$ npx growthrouter link https://umless.com --post show-hn

$ npm install @growthrouter/sdk

import { GrowthRouter } from "@growthrouter/sdk"
const gr = new GrowthRouter(process.env.GROWTHROUTER_KEY)

// after the user verifies their email
await gr.signup({ visitor: req.cookies.gr_id, verified: true })

$ claude mcp add growthrouter -- npx growthrouter-mcp

# then ask
Which post brought real signups this week?

# the agent calls
which_post_worked({ site: "umless", range: "7d" })

[ 02 / 05 ] one campaign, traced

Post, click, signup. Tied together by one campaign ID.

A tracked link carries the campaign. The tag sees the visit, the SDK confirms the signup, and the result lands on the post that earned it.

Stitched togetherUTMs in a sheet, clicks in analytics, signups in your database, joined by hand
GrowthRouterOne ID from post to confirmed signup, readable by you and your agent

campaign show-hn

link umless.com/?gr=show-hn is created for a Show HN post.
post The post goes up on Hacker News, by you or through SceneSmith.
visit A reader clicks through. The tag records source and campaign.
signup They verify their email. The SDK confirms a real signup.
result The signup is credited to show-hn on news.ycombinator.com.
next Your agent reads the result over MCP and drafts the next post.

An illustration of the planned flow, not real data.

[ 03 / 05 ] case studies

Dogfood first

First case studies: our own products.

We test GrowthRouter on products we already run before asking anyone else to. Results get published here as they come in, good or bad.

Umless

Cleans up ums, retakes and dead air in voice recordings.
First tracked test: Show HN, Nov 17
ParleSprint

Spoken French practice for learners.
Case study coming
SceneSmith

Drafts and publishes social posts.
Case study coming

[ 04 / 05 ] open source

Open source at the core.

The tag, the SDK and the MCP server will be MIT-licensed, and the hosted collector AGPL-3.0, so you can read exactly what runs on your site and self-host all of it. The repository goes public with the first release.

Small, readable tag with no third-party scripts (MIT)
SDK and link maker for confirming signups and tagging posts (MIT)
Self-host the collector and dashboard for free (AGPL-3.0)

Design partner planned

$39/month

We install the tag with you and send a weekly "which post worked" report while the hosted version takes shape. Self-hosting stays free; hosted plans will start with a 7-day trial.

Join the waitlist

Not on sale yet.

[ 05 / 05 ] faq

Questions

Can I use it today?

Not yet. GrowthRouter is in development and the first tracked test runs on our own product in November. Join the waitlist and you will get one email when there is something you can install.

How is this different from Google Analytics or PostHog?

Those tell you about traffic. GrowthRouter answers one question: which post brought a confirmed signup. It ties the post, the click and the verified signup together with one campaign ID, and your agent can read it directly.

What counts as a real signup?

A signup your own app confirms, for example a verified email, reported through the SDK. Page views and clicks are tracked too, but results are reported in signups.

Is it free?

Self-hosting is free: the tag, SDK and MCP server are MIT, and the collector is AGPL-3.0. Hosted plans are planned with a 7-day trial. The first teams can join as $39/month design partners.

Does my agent post for me?

No. You post, by hand or with any tool you like. GrowthRouter tracks what happens after, and your agent can use the results to suggest the next post.

Which agents will it work with?

Any agent that can use an MCP server, such as Claude Code or Codex. We are building and testing with Claude first.

Who is building it?

Thoufeek, an indie builder at ThoufeekXLabs, building in public on X.

Find the post that actually worked.