ButterYC W25 landing page report.
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Butterhttps://butter.dev/

Your landing page’s weakest score is CTA.

How Butter ranks

  1. 1.Daytona81
  2. 2.E2B80
  3. 3.Modal76
  4. 4.Microsandbox72
  5. 5.Butter43
Fix CTA
43Growth scoreupdated

category scores

CTA30Trust32Information hierarchy48Mobile web48Value props58
category scoresShowHide
CTA30Trust32Information hierarchy48Mobile web48Value props58

Score over time

90807060504030E2B 80 on May 10 (Wayback)E2B 80 on May 22 (Wayback)E2B 79 on Jun 4 (Wayback)E2B 79 on Jun 16 (Wayback)E2B 79 on Jul 3 (Wayback)E2B 79 on Jul 18 (Wayback)E2B 80 on Jul 31 (Live)Daytona 80 on May 2 (Wayback)Daytona 80 on May 21 (Wayback)Daytona 76 on Jul 1 (Wayback)Daytona 80 on Jul 15 (Wayback)Daytona 79 on Aug 23 (Wayback)Daytona 79 on Sep 3 (Wayback)Daytona 81 on Sep 21 (Live)Modal 75 on Jun 28 (Wayback)Modal 76 on Jul 11 (Wayback)Modal 77 on Jul 25 (Wayback)Modal 76 on Aug 7 (Wayback)Modal 76 on Aug 24 (Wayback)Modal 75 on Sep 8 (Wayback)Modal 76 on Sep 20 (Live)Microsandbox 71 on Apr 20 (Wayback)Microsandbox 73 on May 19 (Wayback)Microsandbox 73 on May 28 (Wayback)Microsandbox 75 on Jun 26 (Wayback)Microsandbox 71 on Jul 21 (Wayback)Microsandbox 74 on Aug 12 (Wayback)Microsandbox 72 on Sep 22 (Live)Butter 41 on Apr 15 (Wayback)Butter 42 on May 20 (Wayback)Butter 43 on Jun 7 (Wayback)Butter 43 on Sep 22 (Live)Apr 15May 20Jun 7Sep 22
Past reportsShow past reportsHide past reports
  1. Sep 22, 202643LiveInformation hierarchy +6 · Trust −6Viewing
  2. Jun 7, 202643Overall +1 · Trust +8 · Information hierarchy −6View →
  3. May 20, 202642Overall +1 · Information hierarchy +6 · Mobile web +4View →
  4. Apr 15, 202641First tracked report — strongest Value props 58, weakest CTA 25View →

CTA

30Poor

Copy, size, verb, cost-feel — does the primary CTA earn the click?

Daytona
E2B
Modal
Microsandbox

Problems

  • no CTA anywhere on the page
  • only action is an inline text link
  • fold is mostly empty space

Trust

32Poor

Proof that the product is real, competent, and safe to try.

Daytona
Microsandbox
Modal
Trust read
ButterNo visible trust signal identified.
E2Bimplicit context E2B may benefit from pre-existing familiarity among its target audience.
DaytonaLogo strip "Agents at these companies use Daytona" with Meta, Cohere, SambaNova, and Writer logos and Case Study links
ModalCustomer logo strip featuring Ramp, Quora, DoorDash, Suno, Cognition, Runway, Substack, PostHog
Microsandbox"backed by y combinator (f26) · apache 2.0" badge above the hero headline

Information hierarchy

48Poor

Does the design help or inhibit what the page is trying to say?

Information hierarchy annotations on the desktop capture12
  1. bVisor text link — The single most prominent interactive element sends visitors away from Butter mid-sentence.
  2. Local Agent Sandboxes headline — Headline is sized like a section subhead, giving the value prop little visual authority over the body text.

Mobile web

48Poor

The phone experience as a first-class citizen.

Mobile web annotations on the mobile capture1
  1. Inline bVisor link — The only tappable action on the page is a small inline text link with no button-sized CTA anywhere.

Value props

58Fair

Title, subtitle, hero — do they sell the product's true value?

Butter’s headline undersellsLocal Agent SandboxesButter 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
  • Developer-honest, jargon-free tone

Could improve

  • 'Incredibly lightweight' has no number behind it
  • H1 is a category label, not a benefit
  • No demo, snippet, or proof of the product working

Competitors

inferred from product, audience, and value prop
#1Daytonadaytona.io81 #2E2Be2b.dev80 #3Modalmodal.com76 #4Microsandboxmicrosandbox.dev72
#5Butter43