Lightspeed Financial Services Group announced an expansion of Lightspeed Connect on 29 October, adding developer resources and trading functionality around short-stock locates and integration testing. Its current documentation sets out the steps an application must complete before it can secure a borrow or submit live orders.[1][2]
Connect provides API access to US equities and equity options, including multi-leg options strategies with up to four legs. It uses a persistent WebSocket connection to exchange JSON messages covering orders, executions, positions and account updates. Developers supply a market-data source or use Lightspeed’s stated partner, Polygon.io.[2]
A locate quote comes before the borrow
Documented short-stock workflow
| Step | What the application does |
|---|---|
| Check borrow status | Look up whether the stock is easy to borrow.Source 3 |
| Request a locate quote | Specify the symbol and quantity; receive availability and the quoted borrow rate.Source 3 |
| Secure the borrow | Submit the locate order after accepting the quote.Source 3 |
| Submit the short order | Use the secured borrow within the applicable short-selling workflow.Source 3 |
That daily expiry is an operating constraint for an automated strategy: yesterday’s locate should not be treated as today’s borrow approval. Lightspeed also says availability and requirements can change. A locate request and a completed short-sale execution are separate stages.[3]
Testing and production use separate environments
Paper trading uses simulated accounts, positions and executions, with credentials separate from production. Developers can test submission, cancellation and replacement messages and inspect acknowledgements and execution reports. The browser console also supports sending sample API messages before the developer writes a full application.[4]
Live access requires the applicable testing and production onboarding. Paper results can demonstrate correct message handling, but simulated fills do not establish live execution quality.[4][2]
The AI-related addition concerns documentation for developers. Lightspeed publishes Markdown versions, an llms.txt index and a full documentation resource for coding assistants. These help an assistant read the API specification; the published workflow still requires message testing and paper validation before production.[5]
Sources & further reading
- Connect API expansion announcement Lightspeed / Business Wire via TMCnet · 29 Oct 2026 · Accessed 29 Oct 2026
- Connect API: products, messages and production access Lightspeed · Accessed 29 Oct 2026
- Stock-locate requests, quotes and expiry Lightspeed · Accessed 29 Oct 2026
- Paper trading and integration testing Lightspeed · Accessed 29 Oct 2026
- Documentation for assisted API development Lightspeed · Accessed 29 Oct 2026