During the last SBC, I started work on a PHP library for interacting with Horizon's API as well as lower-level operations like building and signing transactions.
You can find the library at: https://github.com/zulucrypto/stellar-api
Recent development progress:
- Support for API endpoints that support streaming
- Convenience methods for streaming Effects, Operations, Payments, Transactions, and Ledgers
- Now supports all Operation types
- Additional fields added for Transactions
- Documentation improvements
- Misc. bugfixes and additional convenience methods
I'm now using this library to support another project: https://galactictalk.org/d/480-stellar-network-event-webhook-publisher