Audience
Engineers at AI startups and larger companies who build agents that call third-party SaaS and fintech APIs, including CRM, accounting, payments, email, issue tracking, and developer tools.
About Twinbay
Twinbay is a hosted API simulation platform for developers testing AI agents and applications that call third-party services. Its stateful API twins can return configurable responses and model conditions such as payment declines, rate limits, expired credentials, email bounces, and paginated results. Teams direct compatible SDK requests to a twin, create isolated environments for test runs, inspect request logs, and use the environments in development or CI. The catalog includes twins for services such as GitHub, HubSpot, Plaid, Resend, Klaviyo, Linear, NetSuite, and QuickBooks. Twinbay offers a free plan with limits on twin usage and environment duration, pay-as-you-go twin-hour billing, and an Enterprise option. It is designed for engineers who need repeatable tests of agent behavior without relying on live production accounts or shared provider sandboxes.
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Pricing
Starting Price:
$1/twin-hour
Pricing Details:
A free plan includes up to 5 twins and 1-hour environments. Pay-as-you-go is $1 per twin-hour, billed by the second. Enterprise pricing is custom and annual. Eligible startups may receive $5,000 in credits over 24 months.
Free Version:
Free Version available.
Integrations
Company Information
Twinbay
Founded: 2024
United States
twinbay.ai
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