# GrowthBook

Experiments you host. GrowthBook is MIT core (skip enterprise/) — Optimizely without the experiment seat.

**Replaces:** Optimizely / VWO

**Tier:** Medium

## Problem

Optimizely sells A/B tests and personalization as a seat. VWO is the same experiment seat — this page is a flag and a test, not VWO's every heatmap SKU. You wanted flags and a controlled experiment on a box you run. GrowthBook is MIT core (growthbook/growthbook; last push 26 Oct 2026) — GitHub's license field is Other; skip enterprise/. Unleash is AGPL-3.0 feature flags, not this experiment desk — /compare/growthbook-vs-unleash and /stacks/unleash-flags. PostHog has experiments next to funnels — /replace/amplitude. This is not Optimizely's every personalization, CMS, or Web Experimentation SKU, VWO's every heatmap SKU, or AB Tasty's every widget pack. Heatmaps stay on /replace/smartlook.

## Stack

- [GrowthBook](https://www.growthbook.io) — MIT core flags and experiments (skip enterprise/) — the published Optimizely path
- [Unleash](https://www.getunleash.io) — AGPL-3.0 feature flags if the job is a toggle, not an experiment
- [PostHog](https://posthog.com/) — Product analytics with experiments next to funnels

## Estimated SaaS cost saved

| You stop paying | Typical / year | Self-host instead |
|---|---:|---|
| Optimizely (small team) | $2,400 | GrowthBook + a database |

**About $2,400 / year** on a small team, before you count lock-in.

## Deploy on Railway

Placeholder: GrowthBook (official docs) plus Mongo/Postgres as the project documents. Persist the database. No one-click template in this repo yet — Start on Railway. Feature flags without an experiment UI stay on /stacks/unleash-flags.

[Start on Railway](https://c17.io/go/railway/growthbook-experiments?from=%2Fstacks%2Fgrowthbook-experiments.md)

[Unleash if this is a feature flag, not an A/B test](https://c17.io/stacks/unleash-flags)

## AGENT_PROMPT

```
Replace Optimizely with GrowthBook (https://www.growthbook.io).

- Official self-host docs. Persist the database. Create one flag and one experiment. Do not claim Optimizely personalization, CMS, or Web Experimentation SKUs.
- Skip enterprise/. Feature flags without an experiment UI stay on /stacks/unleash-flags — /compare/growthbook-vs-unleash.
- Write AGENT_PROMPT.md.
```

## FAQ

### GrowthBook or Unleash?

GrowthBook if you want the published Optimizely experiment path. Unleash if the job is a feature flag — /compare/growthbook-vs-unleash.

### Is this VWO or AB Tasty?

VWO is the same published experiment — /replace/vwo. AB Tasty was skipped so the lander stays one path. Heatmaps stay on /replace/smartlook.

### Is this a heatmap?

Heatmaps stay on /replace/smartlook (PostHog). This page is an experiment.

### Are these free?

GrowthBook core is MIT if you skip enterprise/. Unleash is AGPL-3.0. You pay hosting. Template users never pay c17.

Source: https://c17.io/stacks/growthbook-experiments