# Butter Landing Page Growth Score | YC W25

Lazyweb publishes a public search API over its indexed pages; the guide is at https://www.lazyweb.com/agent-access.

Source: https://www.lazyweb.com/yc-w25/butter
Source observed: 2026-10-17T11:00:05.910Z
Last checked: 2026-10-20T08:13:43.067+00:00
Indexed: 2026-10-17T14:32:22.383+00:00

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# Butter landing-page Growth Score

We score Butter’s landing page at **43/100**, updated **September 22, 2026**. Its weakest category is **CTA**, scored **30**.

- **Product:** Butter
- **Website:** [https://butter.dev/](https://butter.dev/)
- **Overall rank in the displayed YC W25 comparison:** #5, Butter 43
- **Fix CTA:** [Fix CTA](https://www.lazyweb.com/plans/checkout?plan=individual&source=growth_score_feature_build_fixes)

## Category scores

| Category | Score | Rating |
|---|---:|---|
| CTA | 30 | Poor |
| Trust | 32 | Poor |
| Information hierarchy | 48 | Poor |
| Mobile web | 48 | Poor |
| Value props | 58 | Fair |

## Score over time

- **September 22, 2026:** 43, live; Information hierarchy +6; Trust −6
- [June 7, 2026](https://www.lazyweb.com/growth-score/history/2026-06-07): 43; Overall +1; Trust +8; Information hierarchy −6
- [May 20, 2026](https://www.lazyweb.com/growth-score/history/2026-05-20): 42; Overall +1; Information hierarchy +6; Mobile web +4
- [April 15, 2026](https://www.lazyweb.com/growth-score/history/2026-04-15): 41; first tracked report; strongest Value props 58, weakest CTA 25

## CTA — 30/100, Poor

We assess copy, size, verb, and cost-feel: whether the primary CTA earns the click.

### Problems identified

- No CTA anywhere on the page
- The only action is an inline text link
- The fold is mostly empty space

### CTA comparison

| Rank | Site | Score |
|---:|---|---:|
| 1 | Daytona | 88 |
| 2 | E2B | 86 |
| 3 | Modal | 72 |
| 4 | Microsandbox | 72 |
| 5 | Butter | 30 |

The CTA rewrite studio is a PRO feature. [Rewrite this CTA](https://www.lazyweb.com/backlog?site=butter.dev#opt-cta-writing) generates primary and secondary CTA options grounded in Butter’s offer and visitor objections.

## Trust — 32/100, Poor

We assess proof that the product is real, competent, and safe to try.

| Site | Trust read |
|---|---|
| Butter | No visible trust signal identified. |
| E2B | Implicit context may benefit from pre-existing familiarity among its target audience. |
| Daytona | Logo strip “Agents at these companies use Daytona” with Meta, Cohere, SambaNova, and Writer logos and Case Study links. |
| Modal | Customer logo strip featuring Ramp, Quora, DoorDash, Suno, Cognition, Runway, Substack, and PostHog. |
| Microsandbox | “backed by y combinator (f26) · apache 2.0” badge above the hero headline. |

### Trust comparison

| Rank | Site | Score |
|---:|---|---:|
| 1 | E2B | 82 |
| 2 | Daytona | 76 |
| 3 | Microsandbox | 72 |
| 4 | Modal | 68 |
| 5 | Butter | 32 |

The PRO proof-section builder can [Build proof section](https://www.lazyweb.com/backlog?site=butter.dev#opt-trust-signals) by selecting proof signals and providing copy and placement for a trust section.

## Information hierarchy — 48/100, Poor

We assess whether the design helps or inhibits what the page is trying to say.

1. **bVisor text link:** The single most prominent interactive element sends visitors away from Butter mid-sentence.
2. **Local Agent Sandboxes headline:** The headline is sized like a section subhead, giving the value proposition little visual authority over the body text.

The PRO layout priority plan turns these callouts into a sequenced page plan. [View layout plan](https://www.lazyweb.com/backlog?site=butter.dev#opt-information-hierarchy).

![Information hierarchy annotations on the desktop capture](https://zlfyzdmohcskkucuunmk.supabase.co/storage/v1/object/public/sites/growth-score/site/butter.dev.jpg?v=2026-09-22T15%3A48%3A19.824%2B00%3A00)

## Mobile web — 48/100, Poor

We assess the phone experience as a first-class part of the landing page.

- **Inline bVisor link:** The only tappable action is a small inline text link with no button-sized CTA anywhere.

![Mobile web annotations on the mobile capture](https://zlfyzdmohcskkucuunmk.supabase.co/storage/v1/object/public/sites/growth-score/site/butter.dev-mobile.jpg?v=2026-09-22T15%3A48%3A19.824%2B00%3A00)

The PRO mobile fix plan converts these findings into a prioritized implementation checklist. [View mobile fixes](https://www.lazyweb.com/backlog?site=butter.dev#opt-mobile-web).

## Value props — 58/100, Fair

The reviewed headline is **“Local Agent Sandboxes”** with the supporting statement: **“Butter is building bVisor, an incredibly lightweight sandbox runtime for AI agents.”**

### Working

- Names the exact category clearly
- “No VMs or remote infra” is a real differentiator
- Uses a developer-honest, jargon-free tone

### Could improve

- “Incredibly lightweight” has no number behind it
- The H1 is a category label, not a benefit
- There is no demo, snippet, or proof of the product working

### Value-proposition comparison

| Rank | Site | Score |
|---:|---|---:|
| 1 | E2B | 78 |
| 2 | Modal | 78 |
| 3 | Daytona | 76 |
| 4 | Microsandbox | 72 |
| 5 | Butter | 58 |

## Competitors

The displayed competitors are inferred from product, audience, and value proposition:

1. [Daytona](https://www.lazyweb.com/growth-score/site/daytona.io) — 81
2. [E2B](https://www.lazyweb.com/growth-score/site/e2b.dev) — 80
3. [Modal](https://www.lazyweb.com/growth-score/site/modal.com) — 76
4. [Microsandbox](https://www.lazyweb.com/growth-score/site/microsandbox.dev) — 72

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