MayStreet

MayStreet is a low-latency market data infrastructure vendor founded in 2012 and acquired by London Stock Exchange Group (LSEG) in May 2022, with maystreet.com now redirecting into LSEG's data feeds pages. The company captures full-depth exchange feeds in raw PCAP form across 300+ venues and sells them through the Bellport feed handler (C++ library, on-premises or managed), a 20+ petabyte Market Data Lake of historical tick data (PCAP/Parquet queried via Athena SQL and the Medusa Python client), the cloud Analytics Workbench (JupyterLab), and the High Performance Query (HPQ) streaming WebSocket API for near-time data. Access is sales-gated and entitlement-managed with no self-serve signup or public developer portal; the public API surface that exists is documented through example "springboard" repositories on the MayStreet GitHub organization rather than a docs site.

MayStreet publishes 2 APIs on the APIs.io network. Tagged areas include Financial, Market Data, Real-Time, Trading, and Low Latency.

MayStreet’s developer surface includes authentication, sandbox, and 8 more developer resources.

🌐 Visit website 📡 Source on GitHub

14.3/100 minimal ▬ flat Agent 17/100 agent aware Full breakdown ↓
scored 2026-07-27 · rubric v0.5

2 APIs

FinancialMarket DataReal-TimeTradingLow LatencyTick DataOrder BookEquitiesOptionsFeed HandlersPCAP

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 14.3/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 3.5 / 20

Commercial Clarity 0.0 / 20

Operational Transparency 0.7 / 13

Governance 0.0 / 12

Discoverability 8.0 / 10

Agent readiness — 17/100 · agent aware

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/maystreet: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 2

Individual APIs this provider publishes, each with its own machine-readable definition.

Get Started 1

Portal, sign-up, and the first successful call

Sandbox

Sandbox

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

Conventions

Conventions

ErrorCatalog

ErrorCatalog

Lifecycle

Lifecycle

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Company 2

The organization behind the API

Website

Website

LinkedIn

Source (apis.yml)

aid: maystreet
url: https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/apis.yml
name: MayStreet
kind: company
description: MayStreet is a low-latency market data infrastructure vendor founded in 2012 and acquired by London Stock Exchange
  Group (LSEG) in May 2022, with maystreet.com now redirecting into LSEG's data feeds pages. The company captures full-depth
  exchange feeds in raw PCAP form across 300+ venues and sells them through the Bellport feed handler (C++ library, on-premises
  or managed), a 20+ petabyte Market Data Lake of historical tick data (PCAP/Parquet queried via Athena SQL and the Medusa
  Python client), the cloud Analytics Workbench (JupyterLab), and the High Performance Query (HPQ) streaming WebSocket API
  for near-time data. Access is sales-gated and entitlement-managed with no self-serve signup or public developer portal;
  the public API surface that exists is documented through example "springboard" repositories on the MayStreet GitHub organization
  rather than a docs site.
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/maystreet.png
tags:
- Financial
- Market Data
- Real-Time
- Trading
- Low Latency
- Tick Data
- Order Book
- Equities
- Options
- Feed Handlers
- PCAP
created: '2026-07-21'
modified: '2026-07-22'
specificationVersion: '0.19'
apis:
- aid: maystreet:maystreet-high-performance-query-api
  name: MayStreet High Performance Query (HPQ) API
  tags:
  - Market Data
  - WebSocket
  - Streaming
  - Tick Data
  - Near-Time
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://github.com/maystreet/workbench-hpq-springboard
  baseURL: wss://mdx.uat.maystreet.com
  properties:
  - url: https://github.com/maystreet/workbench-hpq-springboard
    type: Documentation
  description: Low-latency, near-time market data query API delivered as a streaming WebSockets service so clients can process
    arbitrarily-sized result sets frame-by-frame without pagination. Publicly documented only through the workbench-hpq-springboard
    example notebooks and hpq.py client on GitHub, which name the UAT endpoint wss://mdx.uat.maystreet.com (the production
    mdx.maystreet.com host resolves in DNS but is entitlement-gated and not publicly reachable). Access requires a MayStreet/LSEG
    Analytics Workbench entitlement.
- aid: maystreet:maystreet-data-lake-query-api
  name: MayStreet Market Data Lake Query API
  tags:
  - Market Data
  - Historical
  - Tick Data
  - SQL
  - Python
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://github.com/maystreet/workbench-data-lake-springboard
  properties:
  - url: https://github.com/maystreet/workbench-data-lake-springboard
    type: Documentation
  - url: https://github.com/maystreet/workbench-medusa-springboard
    type: Documentation
  description: Query access to MayStreet's 20+ petabyte Market Data Lake of historical exchange data captured as PCAP and
    converted to Parquet, exposed as Athena SQL plus a growing set of client functions through the Medusa2 Python client library
    inside Analytics Workbench. The Medusa client also reaches Refinitiv Tick History and Machine Readable News History stores
    backed by Google BigQuery. Publicly documented only via springboard example repositories on GitHub; no public REST endpoint
    or self-serve access is documented.
common:
- type: DomainSecurity
  url: security/maystreet-domain-security.yml
- type: Authentication
  url: authentication/maystreet-authentication.yml
- type: Conventions
  url: conventions/maystreet-conventions.yml
- type: ErrorCatalog
  url: errors/maystreet-problem-types.yml
- type: Sandbox
  url: sandbox/maystreet-sandbox.yml
- type: Lifecycle
  url: lifecycle/maystreet-lifecycle.yml
- type: LLMsTxt
  url: llms/maystreet-llms.txt
- type: Website
  url: https://maystreet.com/
- type: GitHubOrganization
  url: https://github.com/maystreet
- type: LinkedIn
  url: https://www.linkedin.com/company/maystreet
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

MayStreet

Kin Score

APIs 2

MayStreet High Performance Query (HPQ) API

MayStreet Market Data Lake Query API

Security Posture 2

Maystreet Authentication

Maystreet Domain Security

Resources