# MayStreet

> MayStreet is a low-latency market data infrastructure vendor (founded 2012, acquired by London Stock Exchange Group in May 2022). It captures full-depth exchange feeds across 300+ venues and delivers them through the Bellport C++ feed handler, a 20+ petabyte Market Data Lake (PCAP/Parquet via Athena SQL and the Medusa2 Python client), the cloud Analytics Workbench (JupyterLab), and the High Performance Query (HPQ) streaming WebSocket API. Access is sales-gated and entitlement-managed: there is no public developer portal, self-serve signup, or published OpenAPI; the public technical surface is the "springboard" example repositories on GitHub.

Generated by API Evangelist from the maystreet catalog repo (no provider llms.txt exists). Provenance: generated 2026-07-22.

## APIs

- [High Performance Query (HPQ) API](https://github.com/maystreet/workbench-hpq-springboard): Low-latency, near-time market data query API delivered as a streaming WebSocket service (JSON requests, frame-by-frame streamed JSON responses, query_status control lifecycle). UAT endpoint wss://mdx.uat.maystreet.com; entitlement-gated. A legacy HPQ REST API exists but is deprecated.
- [Market Data Lake Query API](https://github.com/maystreet/workbench-data-lake-springboard): Historical tick data (PCAP converted to Parquet) queried with AWS Athena SQL and the Medusa2 Python client inside Analytics Workbench; Refinitiv Tick History and MRN History reached via Google BigQuery.

## Docs

- [HPQ springboard](https://github.com/maystreet/workbench-hpq-springboard): hpq.py WebSocket client plus notebooks covering pagination, continuation/resume, error handling, and market-data queries.
- [Data Lake springboard](https://github.com/maystreet/workbench-data-lake-springboard): Example Athena SQL queries, Dask distributed queries, user-defined tables.
- [Medusa springboard](https://github.com/maystreet/workbench-medusa-springboard): Medusa2 Python client examples.
- [Bellport springboard](https://github.com/maystreet/workbench-bellport-springboard-xdp-v2): Compiling a C++ app against the Bellport feed-handler library.
- [MayStreet GitHub organization](https://github.com/maystreet)

## Catalog artifacts (API Evangelist)

- [apis.yml](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/apis.yml): APIs.json catalog entry
- [Authentication profile](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/authentication/maystreet-authentication.yml): Workbench JWT bearer + MayStreet-Data-Lake-Secret header schemes
- [Conventions](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/conventions/maystreet-conventions.yml): HPQ request lifecycle, streaming, pagination/continuation semantics
- [Error catalog](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/errors/maystreet-problem-types.yml): reject / mid-stream / protocol / canceled failure modalities
- [Sandbox](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/sandbox/maystreet-sandbox.yml): UAT/staging environments + failure-simulation endpoint (entitlement-gated)
- [Lifecycle](https://raw.githubusercontent.com/api-evangelist/maystreet/refs/heads/main/lifecycle/maystreet-lifecycle.yml): deprecated HPQ REST API, no public status page/SLA

## Optional

- [LSEG acquisition press release](https://www.lseg.com/en/media-centre/press-releases/2022/lseg-to-acquire-maystreet)
- Contact: sales via LSEG; no public developer support channel.