Analytics and monitoring decision
Stellar
A competent developer can build a useful, self‑hosted minimal A/B testing workflow (editor, snippet, bucketing, analytics) in a few weeks, but matching Stellar’s full product (heatmaps, AI insights/MCP, enterprise onboarding, scale and SLAs) is larger and would justify continuing to pay.
Visit website↗$29/mo
$348/yr
Read off the official pricing page.
$100one-off110 h to build
$250/mo6 h/mo upkeep
On cash alone, building overtakes the subscription at 9 seats.
Open-source builds that already do this
Every project below is open source and already does this job today. Fork one, self-host it, or take the parts you need - the build prompt further down assumes an empty file, and this is the shortcut past that. Licences differ; check the one on each card before you ship. All Stellar alternatives, with the arithmetic →
What a replacement has to do
- Install a small JS snippet on your site, open the visual editor to create variants, assign traffic and goals, collect visitor events, and view experiment results and recommendations in the dashboard.
What it still won’t have
- Priority onboarding, dedicated migration help, and enterprise SLAs
- Built-in AI insights & MCP chat integrations
- Polished heatmaps & funnels as implemented by the vendor
- Scale-ready hosted infra, CDN distribution & DDoS protection
- Cookieless data-handling/legal assurances and a Data Processing Agreement provided by vendor
What remains hard
- Product polish and ongoing maintenance
First-year cost
Keep paying
Paying is—cheaper in year one.
On cash alone, building overtakes the subscription at 9 seats.
Money you would actually spend
Time you would spend
—
What you would spend
What we assumed
The verdict above measures whether you could build it. This one is only about money.
Runnable build prompt
Build a self-hosted lightweight A/B testing service using React for the visual editor, a small client JS snippet served from a CDN, Node.js + Express for APIs, Redis for bucketing, and Postgres (or ClickHouse) for event storage. Core features in scope: CDN-served async snippet (<=10KB), WYSIWYG editor to create/save variants, deterministic bucketing and traffic allocation APIs, browser event collector and ingestion pipeline, a Bayesian stats engine that reports lift and confidence, GA4 export webhook, simple dashboard to list experiments and winners. Out of scope: heatmaps & funnel visualizations, enterprise SSO/SSO provisioning, dedicated onboarding, and AI-powered recommendations/MCP chat. Include error handling, input validation, tests for bucketing correctness and stats, containerized deployment manifests (Docker + simple Kubernetes or ECS), and documentation for installing the snippet on common CMS (Shopify, WordPress, Webflow).
How we checked
How the score was reached
- Partly verdict base52
- An open-source build was found+5
- 4 cited sources+3
- Price verified on pricing page+3
- Evidence score63
The base comes from the verdict. Everything under it is a check that either happened or did not, and each one is a fact frozen in this record rather than a judgement made at render time - so the same evidence always produces the same number.
How scoring works →Cited sources · 4
Every page the run actually retrieved.
- official productStellar | The Fastest A/B Testing Platform for Growth Teams
- official docsStellar Docs & Resources
- open sourcegrowthbook/growthbook
- open sourcePostHog/posthog
Integrity checks
What held up, and what did not.
