# Development Timeline

zkBob has been in research and development since December 2020. The original concept was initiated by members of the now defunct xDai research group and the [ZeroPool](https://zeropool.network/) team. Chains with robust infrastructure led contributors to select Polygon and then Optimism for deployment.

## zkBob Timeline

* December 2020: R\&D initiated.
* June 2021: Prototyping and ongoing contract development on xDai.
* December 2021: New contributors improve contracts, implement applications, prepare Kovan deployment.
* March 2022: Testing, bug fixing, protocol updates and enhancements.
* August 2022:  Prep for beta launch and trusted ceremony, select Polygon for initial deployment.
* April 2023: Second deployment on Optimism, making zkBob a multichain app.
* July 2023: First ETH pool deployed on Optimism.
* August 2023: [Payment Link](https://zkbob.com/payment-link) introduced.
* Ongoing: zkBob pools are self-sustaining and available on Polygon, Optimism and Tron. Periodic reviews are conducted to determine appropriate limits and other updates to the protocol.