Mockingbird
Emulator catalog

Emulators

125 stateful emulators. Each one declares the parity it keeps with its vendor. Every emulator is isomorphic: the same package runs in the browser, in a worker, and on a server. Open one for a live playground backed by the real package.

125 emulators

Amazon S3

Storage
Featured

Stateful S3 emulator that answers exactly as MinIO does: every bucket, object, multipart, versioning, object-lock, policy and auth API, verified against recorded MinIO transcripts.

Parity: Every MinIO S3 API, byte-exact against recorded MinIO transcripts9 operations CLI

Junction

Health & labs
Featured

Stateful emulator of the Junction (Vital) user API driven by its OpenAPI contract and verified by differential property tests against the Junction sandbox.

Parity: Users, orders, and lab results42 operations CLI

PostgreSQL

Databases
Featured

Pure TypeScript in-memory PostgreSQL implementation with zero WASM/native dependencies

Parity: In-memory SQL engineSQL engine CLI

Stripe

Payments
Featured

Stateful emulator of the Stripe API (accounts by key, customers, payments, subscriptions that renew, pause, resume and cancel, invoices, checkout with a hosted page, a hosted customer portal, a Stripe.js stand-in, signed webhooks) at API versions 2024-06-20 and 2025-02-24.acacia, verified by differential property tests against Stripe test mode.

Parity: Payments, billing, and webhooks122 operations CLI

AHA

Health & labs

Stateful AHA phlebotomy emulator with signed HTTP orders, status webhooks, and a real deterministic SSH/SFTP result server.

Parity: Phlebotomy orders and result files2 operations CLI

Airtable

Productivity

Stateful Airtable emulator: OAuth, base schemas, fields and validated records.

Parity: OAuth, base metadata, fields and record creation6 operations CLI

Amazon API Gateway REST API

Infrastructure

Work-in-progress Amazon API Gateway REST API transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Certificate Manager

Identity

Stateful Amazon Certificate Manager emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Cloud Control API

Storage

Work-in-progress Amazon Cloud Control API transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon CloudFormation

Storage

Work-in-progress Amazon CloudFormation transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon CloudWatch Logs

Observability

Stateful Amazon CloudWatch Logs emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon CloudWatch Metrics

Observability

Stateful Amazon CloudWatch Metrics emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Cognito

Identity

Stateful Amazon Cognito User Pools emulator for AWS SDK and browser authentication tests.

Parity: User pools and browser auth3 operations CLI

Amazon Config

Observability

Work-in-progress Amazon Config transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Data Firehose

Communication

Stateful Amazon Data Firehose emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon DynamoDB

Databases

Stateful Amazon DynamoDB emulator with typed items, expressions, indexes, pagination, transactions, and streams.

Parity: Items, indexes, and transactions1 operations CLI

Amazon DynamoDB Streams

Storage

Work-in-progress Amazon DynamoDB Streams transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Elastic Compute Cloud

Infrastructure

Work-in-progress Amazon Elastic Compute Cloud transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Elasticsearch Service

Storage

Work-in-progress Amazon Elasticsearch Service transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon EventBridge Scheduler

Communication

Stateful Amazon EventBridge Scheduler emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Identity and Access Management

Identity

Stateful Amazon Identity and Access Management emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Key Management Service

Identity

Stateful Amazon Key Management Service emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Kinesis Data Streams

Communication

Stateful Amazon Kinesis Data Streams emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Lambda

Infrastructure

Work-in-progress Amazon Lambda transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon OpenSearch Service

Storage

Work-in-progress Amazon OpenSearch Service transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Redshift

Storage

Work-in-progress Amazon Redshift transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Resource Groups

Storage

Stateful Amazon Resource Groups emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Resource Groups Tagging API

Storage

Stateful Amazon Resource Groups Tagging API emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Route 53

Infrastructure

Work-in-progress Amazon Route 53 transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Route 53 Resolver

Infrastructure

Work-in-progress Amazon Route 53 Resolver transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon S3 Control

Storage

Work-in-progress Amazon S3 Control transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Security Token Service

Identity

Stateful Amazon Security Token Service emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Simple Email Service

Communication

Stateful Amazon Simple Email Service emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Simple Notification Service

Communication

Stateful Amazon Simple Notification Service emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Simple Workflow Service

Communication

Work-in-progress Amazon Simple Workflow Service transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon SQS

Communication

Stateful Amazon SQS emulator with visibility, FIFO ordering, deduplication, batches, and redrive.

Parity: Queues, FIFO, and batches1 operations CLI

Amazon Support API

Observability

Work-in-progress Amazon Support API transport scaffold; vendor operations are not implemented.

Parity: Scaffold only; no vendor operations implemented or verified0 operations CLI

Amazon Systems Manager Parameter Store

Identity

Stateful Amazon Systems Manager Parameter Store emulator with AWS SDK wire compatibility and deterministic local controls.

Parity: Documented operations; LocalStack differential scenarios7 operations CLI

Amazon Textract

AI & speech

Stateful Amazon Textract emulator with document analysis jobs, graph blocks, pagination, and deterministic notifications.

Parity: Document analysis jobs1 operations CLI

App Store Connect

Identity

App Store Connect JSON:API emulator with verified ES256 JWTs and TestFlight membership state.

Parity: JWT-authenticated apps, users, invitations and TestFlight groups14 operations CLI

Apple

Identity

Stateful Apple public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle6 operations CLI

AWS

Infrastructure

Combined S3, SQS, IAM and STS provider endpoint emulator with native controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle29 operations CLI

AWS Bedrock

AI & speech

Stateful, scriptable emulator of AWS Bedrock Runtime (Converse, ConverseStream, InvokeModel incl. Titan embeddings, Nova Sonic bidirectional streams over h2c) and AgentCore InvokeHarness, with exact event-stream framing.

Parity: Bedrock Runtime and AgentCore5 operations CLI

AWS ECS

Communication

AWS ECS Fargate RunTask acceptance and failure emulator.

Parity: Fargate task acceptance, failures and container overrides1 operations CLI

AWS Elemental MediaConvert

Communication

Stateful AWS Elemental MediaConvert emulator with endpoint discovery, async jobs, EventBridge events, and deterministic S3 outputs.

Parity: Jobs and EventBridge4 operations CLI

AWS EventBridge

Communication

Seeded AWS EventBridge rule and ECS target discovery with pagination.

Parity: Seeded rule and target discovery with pagination1 operations CLI

AWS IoT Core

Communication

Stateful emulator of the AWS IoT Core data plane: SigV4-signed HTTP Publish and the MQTT 5 message broker over TCP and WebSocket, with custom-authorizer policies and persistent sessions.

Parity: HTTP Publish with SigV4, MQTT 5 sessions and custom-authorizer policies1 operations CLI

AWS Polly & Transcribe

AI & speech

Stateful emulator of AWS Polly (SynthesizeSpeech, StartSpeechSynthesisStream) and Transcribe (streaming over h2c, batch jobs), with exact event-stream framing and scripted transcripts.

Parity: Polly and Transcribe4 operations CLI

AWS Secrets Manager & SSM

Identity

Stateful AWS Secrets Manager and SSM Parameter Store emulator with versions, stages, rotation, and redacted controls.

Parity: Secrets Manager and Parameter Store1 operations CLI

AWS Step Functions

Productivity

Stateful AWS Step Functions emulator with idempotent executions, callbacks, deterministic transitions, and history.

Parity: Executions and history1 operations CLI

Brevo

Marketing

Stateful Brevo contact creation, external-id updates and email deletion emulator.

Parity: Contact identity and CRUD4 operations CLI

CareTalk

Health & labs

Stateful emulator of CareTalk's external API: client-login tokens, GetForm definitions, SavePatientForm rounds, patient search/insert, states, free slots and appointments.

Parity: Forms, patients, and appointments9 operations CLI

Checkr

Identity

Stateful Checkr candidates, invitations, hierarchy and report reads.

Parity: Candidates, invitation lifecycle, hierarchy and report reads10 operations CLI

Clerk

Identity

Stateful Clerk public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle44 operations CLI

Cloudflare Turnstile

Identity

Deterministic Cloudflare Turnstile Siteverify token validation.

Parity: Siteverify JSON/form tokens, expiry and replay1 operations CLI

Customer.io

Marketing

Stateful emulator of Customer.io: Segment-compatible CDP (identify/track/batch, SDK drop-in), App API transactional email/SMS/inbox sends with an outbox, message catalog, link-click tracking, and signed reporting webhooks.

Parity: CDP, messaging, and webhooks14 operations CLI

Daily

Communication

Stateful emulator of the Daily.co REST API: rooms, presence, eject, meeting tokens (minted and self-signed HS256, verified and decodable), and transcription/recording webhooks with transcripts written to S3.

Parity: Rooms, tokens, and webhooks9 operations CLI

Docker Engine

Infrastructure

Stateful Docker Engine API v1.52 emulator with portable controls and Node transport.

Parity: Docker Engine container lifecycle, logs and streams12 operations CLI

EasyPost

Maps & logistics

Stateful emulator of the EasyPost trackers API: create/re-use trackers, EasyPost's test tracking codes, admin status transitions and EasyPost's error envelope.

Parity: Trackers3 operations CLI

Edamam

Health & labs

Stateful emulator of the Edamam APIs our apps call: food-database parser, nutrients and image analysis, nutrition analysis, recipe search v2, meal-planner select and shopping lists, over a built-in food and recipe corpus.

Parity: Food, nutrition, and recipes10 operations CLI

ElevenLabs

AI & speech

Local ElevenLabs text-to-speech emulator: decodable MP3 and raw PCM answers, scripted audio replies, vendor error envelopes and redacted call metadata without billed synthesis.

Parity: Text to speech: MP3, raw PCM and WAV answers, errors, scripted audio1 operations CLI

EMQX

Communication

Stateful emulator of the EMQX 5 MQTT broker: MQTT 5 over TCP and WebSocket, password and JWT authentication with JWT ACLs, persistent sessions with offline QoS 1 queues, and the REST v5 publish and client-kick endpoints.

Parity: MQTT 5 sessions, JWT ACLs, REST publish and client kick2 operations CLI

Firebase Cloud Messaging

Communication

Stateful emulator of the Firebase Cloud Messaging HTTP v1 send API used by firebase-admin: fixture projects and registration tokens, an outbox, and a device inbox.

Parity: FCM HTTP v1 send1 operations CLI

FirstPromoter

Marketing

Stateful emulator of the FirstPromoter v2 API: promoters (adopt-before-create by cust_id), signup tracking by tid / promoter_id / ref token, iframe login, archive, and Basic-auth lead_becomes_referral webhooks.

Parity: Promoters, referrals, and webhooks17 operations CLI

Fitbit

Health & labs

Stateful Fitbit legacy Web API emulator: OAuth PKCE and revoke, activity log, sleep and daily summary with synthetic data.

Parity: OAuth PKCE, activity log, sleep and daily summary8 operations CLI

Flex

Payments

Stateful emulator of the Flex HSA/FSA payments API: products (recorded catalog corpus), checkout sessions in payment, subscription, off-session and setup modes, subscriptions, customers, setup intents, refunds, the hosted checkout page, and Svix-signed webhooks.

Parity: Checkout, subscriptions, and webhooks14 operations CLI

Formbricks

Productivity

Stateful emulator of open-source Formbricks: the client environment state (seeded with a synthetic survey corpus), response creation with upstream's validation and {code, message, details} errors, the v1 management API, the widget script, and signed response webhooks.

Parity: Surveys, responses, and webhooks8 operations CLI

Fullscript

Health & labs

Stateful emulator of the Fullscript lab-ordering API: per-practitioner OAuth, clinic, session grants, forward-only lab orders with results, lab-order events, expiring result PDFs, and Fullscript-Signature webhooks.

Parity: Lab orders and result files10 operations CLI

Garmin Health

Health & labs

Stateful Garmin Health emulator: OAuth PKCE, backfill requests, push and ping webhooks and deregistration.

Parity: OAuth PKCE, backfill requests, push and ping webhooks6 operations CLI

Gene by Gene

Health & labs

Stateful emulator of Gene by Gene's Nucleus API v2 and auth host: tokens with credential blocking, catalog, shipping quotes, orders, kits, demographics, three-layer cancel, results with presigned downloads and S3 writes, subscriptions, and GxG-signed webhooks.

Parity: Orders, kits, results, and webhooks30 operations CLI

GitHub

Infrastructure

Stateful GitHub REST API 2026-03-10 emulator for repository, reference and pull-request scenarios.

Parity: GitHub REST repositories, refs and pull requests239 operations CLI

Google

Productivity

Stateful Google public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle62 operations CLI

Google Ads & GA4

Marketing

Google Ads v25 and GA4 emulator: GAQL metrics, budget mutations, conversion uploads and analytics events/reports.

Parity: GAQL metrics, campaign budgets, conversions and GA4 events/reports8 operations CLI

Google Calendar

Productivity

Stateful emulator of the Google Calendar v3 API and Google OAuth our EMR calls: events list/insert/update/delete/watch, channels.stop, calendarList/calendars, token exchange/refresh/revoke and userinfo, with signed-by-header push notifications.

Parity: Events and OAuth12 operations CLI

Google Maps

Maps & logistics

Emulator of Google Places Autocomplete / Details / Find Place, the Geocoding API, a Maps JavaScript (places) shim and the Address Validation API (USPS CASS/DPV verdicts), over a QA address corpus, with Google's status codes and fault presets.

Parity: Places, geocoding, and address validation6 operations CLI

Grafana Tempo

Observability

Stateful emulator of Grafana Tempo: OTLP/HTTP trace ingest (JSON and protobuf), TraceQL search, trace lookup by id and tag-name discovery over one tenant-scoped store.

Parity: OTLP trace ingest, TraceQL search, trace lookup and tag names4 operations CLI

Healthie

Health & labs

Stateful emulator of the Healthie GraphQL API (legacy surface): signIn, users, currentUser, updateUser/updateClient (incl. multipart avatar), locations, documents and folders with served downloads, form answers, offerings, billing items, and the IP-allowlisted status webhooks.

Parity: GraphQL users, documents, and billing2 operations CLI

Hermes Agent

Infrastructure

Hermes peer-run API emulator with portable scripted lifecycle controls.

Parity: Pinned Hermes run lifecycle and recovery3 operations CLI

Infisical

Identity

Stateful Infisical emulator: Universal Auth, scoped machine/service tokens and versioned project environment secrets.

Parity: Universal Auth and versioned raw secrets6 operations CLI

Intercom

Communication

Stateful emulator of the Intercom REST API 2.11: contacts (search, create with 409 on duplicates, update, get), conversations (create with Idempotency-Key, reply as JSON or multipart, close/open, get, cursor search), admins, and X-Hub-Signature-signed admin reply/close/open webhooks.

Parity: Contacts, conversations, and webhooks14 operations CLI

Kill Bill

Payments

Stateful Kill Bill billing emulator with accounts, subscriptions, invoices, payments, credits, retries, catalog, and clock controls.

Parity: Accounts, subscriptions, and invoices16 operations CLI

Klaviyo

Marketing

Stateful emulator of the Klaviyo events API: JSON:API event create (Ordered Product, Placed Order), event reads, unique_id dedupe, JSON:API errors and an outbox.

Parity: Events3 operations CLI

LifeFile

Pharmacy

Best-guess LifeFile pharmacy order gateway and Basic-auth Data Push emulator.

Parity: Orders, cancellation and Data Push (best guess)2 operations CLI

Linear

Productivity

Stateful Linear public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle7 operations CLI

LiveKit

Communication

Stateful LiveKit emulator with Twirp room APIs, JWT grants, participants, data, SIP/egress controls, and signed webhooks.

Parity: Rooms, grants, and webhooks6 operations CLI

LlamaCloud

AI & speech

Stateful emulator of the LlamaCloud platform API: project and pipeline lookup, pipeline documents, and deterministic (scripted or term-overlap) retrieval, verified against the official llama_cloud_services SDK.

Parity: Pipelines and retrieval10 operations CLI

Mailosaur

Communication

Stateful emulator of the Mailosaur email/SMS testing API (messages search, get, delete, long-poll) with an HTTP ingest so other emulators can drop mail in (Mockingbird service contract).

Parity: Messages and ingest8 operations CLI

Medplum

Health & labs

Stateful emulator of the self-hosted Medplum server (FHIR R4 REST, OAuth2 and admin API), proven at parity with a real self-hosted Medplum used as the oracle.

Parity: FHIR R4, OAuth, and admin54 operations CLI

Meta

Marketing

Stateful emulator of Meta's Conversions and Marketing APIs: server events, deduplication, campaign objects, insights, pagination and Graph error envelopes.

Parity: Conversions events and marketing insights3 operations CLI

Microsoft

Identity

Stateful Microsoft public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle12 operations CLI

MongoDB Atlas

Infrastructure

Stateful MongoDB Atlas public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle24 operations CLI

Notion

Productivity

Notion 2022-06-28 OAuth, database search and page creation emulator.

Parity: 2022-06-28 database search and page creation4 operations CLI

OAuth & Social Login

Identity

Social-login emulator with Google, Apple, Microsoft, GitHub and generic OIDC profiles, private relay identities, reproducible edge cases, signed tokens and an accessible UI.

Parity: OIDC and social login32 operations CLI

Okta

Identity

Stateful Okta public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle56 operations CLI

OpenAI

AI & speech

Local scripted OpenAI emulator: chat/tool loops, SSE, embeddings, models, files and staged uploads without billed inference.

Parity: Scripted chat/tool calls, SSE, embeddings, models, files and uploads16 operations CLI

OpenTelemetry

Observability

Stateful emulator of an OTLP/HTTP collector (JSON and protobuf traces and logs) and the OpenObserve search API over the same store.

Parity: OTLP traces and logs10 operations CLI

Optimal DX

Health & labs

Stateful emulator of the (retired) Optimal DX partner API: patients, partner links, HL7 and structured lab imports, Functional Health Reports (JSON/PDF), webhook registrations, and signed PatientTest webhooks.

Parity: Patients, reports, and webhooks15 operations CLI

Oura

Health & labs

Stateful Oura v2 emulator: wearable collections, OAuth refresh and namespace-isolated synthetic data.

Parity: OAuth refresh and wearable collection windows10 operations CLI

Paddle

Payments

Stateful emulator of the Paddle Billing API (customers, addresses, businesses, products, prices, transactions with computed totals, subscriptions with pause/resume/cancel and renewals, events) with Paddle-Signature webhooks and admin routes that simulate checkout, renewals and failed payments (Mockingbird service contract).

Parity: Billing, subscriptions, and webhooks42 operations CLI

Payload CMS

Productivity

Stateful emulator of the Payload CMS collection REST API: paginated finds with a where-query subset, find by id, a seeded marketing collection and admin-editable documents.

Parity: Collection REST2 operations CLI

Persona

Identity

Stateful emulator of the Persona identity-verification API: inquiry create, list (reusable lookup), get, a hosted flow page, admin lifecycle transitions, and Persona-Signature webhooks.

Parity: Inquiries and webhooks5 operations CLI

Pharmetika

Pharmacy

Stateful emulator of the Pharmetika compounding-pharmacy provider portal: clinics, patients, medication-order validate / EPCS prepare / submit / lookup, the v7 cancel, the medication-template catalog, and status webhooks.

Parity: Medication orders and webhooks9 operations CLI

Plane

Productivity

Stateful emulator of the Plane REST API v1: cursor-paginated work items, comments, links, states and labels, with Plane's rate limit and error shapes.

Parity: Work items, comments, and states16 operations CLI

Polar

Health & labs

Stateful Polar AccessLink v3 emulator: OAuth consent and code exchange, user registration and the 30-day exercise window.

Parity: OAuth code exchange, user registration and exercise windows5 operations CLI

PostHog

Observability

Stateful emulator of PostHog: /flags v2 and legacy /decide evaluation with per-test flag, variant and payload control, remote config, gzip/base64 capture (/batch/, /e/, /i/v0/e/), recordings intake, and the feature-flag management and HogQL API slice.

Parity: Flags, capture, and HogQL21 operations CLI

Prism Labs

Health & labs

Stateful emulator of the Prism Labs body-scan API: subjects, scans, presigned capture upload, processing stages to READY, and deterministic body-composition, measurement, health-report and asset results.

Parity: Body scans and measurements11 operations CLI

reCAPTCHA

Identity

Deterministic reCAPTCHA v3 browser shim and single-use Siteverify emulator.

Parity: v3 browser API and token verification2 operations CLI

Redis

Databases

In-process Redis RESP server for tests: strings, hashes, lists, sets, sorted sets, streams, transactions, pub/sub, and a Lua subset, with an injected clock. Not an HTTP emulator.

Parity: RESP replies, expiration, transactions, and streamsReal server CLI

Resend

Communication

Stateful emulator of the Resend email API (send with idempotency, received emails, attachments) with an outbox and Svix-signed inbound webhooks (Mockingbird service contract).

Parity: Email send and inbound webhooks25 operations CLI

RxVortex

Pharmacy

Stateful emulator of the RxVortex (Strive) pharmacy API: OAuth token, order submit, status, cancel, recovery by sender order id, preset catalog, and signed status webhooks.

Parity: Orders and status webhooks5 operations CLI

Sentry

Observability

Stateful Sentry emulator: SDK envelope/store/minidump ingestion, events, issues, attachments and deterministic transport controls.

Parity: SDK ingestion, events, issues and attachments12 operations CLI

Slack

Communication

Stateful emulator of Slack incoming webhooks, the Web API, and the Socket Mode control plane, with an outbox of every alert the app sent.

Parity: Webhooks, Web API, and Socket Mode75 operations CLI

SQLite

Databases

Pure TypeScript in-memory SQLite implementation with zero WASM/native dependencies

Parity: In-memory SQL engineSQL engine CLI

Suunto

Health & labs

Stateful Suunto Cloud API emulator: OAuth, workouts and 24/7 samples with namespace-isolated synthetic data.

Parity: OAuth, workouts and 24/7 sleep, activity and daily samples7 operations CLI

Tavily

AI & speech

Scripted Tavily search and extraction without web crawling.

Parity: Scripted search, URL extraction and SDK errors2 operations CLI

Twilio

Communication

Stateful emulator of Twilio Verify, Lookup v2, Messaging and Recordings on one port, with signed inbound SMS and voice webhooks (Mockingbird service contract).

Parity: Verify, Lookup, Messaging, and voice80 operations CLI

Unsplash

Storage

Deterministic Unsplash search and local synthetic image fixtures.

Parity: Photo search, pagination and attribution3 operations CLI

Vanta

Productivity

Vanta scoped OAuth, compliance evidence and offboarding emulator.

Parity: OAuth, people, evidence uploads and offboarding10 operations CLI

Vercel

Infrastructure

Stateful Vercel public vendor API emulator with native namespaces, checkpoints and test controls.

Parity: Vendor API workflows compared with the pinned Emulate package oracle52 operations CLI

Vercel Blob

Storage

Stateful Vercel Blob emulator: binary uploads, public downloads, metadata, cursor listing and multipart commits.

Parity: Uploads, public bytes, metadata, list, copy, delete and multipart7 operations CLI

Vibe

Marketing

Vibe OAuth and asynchronous campaign-spend report emulator.

Parity: OAuth and asynchronous JSON reports4 operations CLI

VPI

Pharmacy

Stateful emulator of the VPI compounding pharmacy API: JWT authentication, products, clinic, patients, providers, saveNewPrescription drafts and the three paged prescription status lists.

Parity: Prescriptions and status lists18 operations CLI

Wholescripts

Pharmacy

Stateful emulator of the Wholescripts supplement fulfilment API: product and private-label catalogs, order submit, status polling and cancel, with admin status transitions.

Parity: Catalogs, orders, and cancel5 operations CLI

WHOOP

Health & labs

Stateful WHOOP v2 emulator: collections, related-sleep recovery windows, and OAuth refresh.

Parity: OAuth refresh and wearable collection windows7 operations CLI

WorkOS

Identity

Stateful WorkOS AuthKit emulator with signed sessions, rotating refresh tokens and user pagination.

Parity: AuthKit codes, signed sessions, refresh and user pagination4 operations CLI
↑↓ to navigate↵ to open