php laravel to enhance an existing project

This is a set of API's written in PHP Laravel. The API's connect to another slave core PHP API to obtain data. This Laravel set of API's add a layer of security so that some of the slave API's are not called without proper tokens. Tokens expire in 24 hours. The API's are used to build a website. The API's receive encrypted POST calls and they - base64_decode in memory - decrypted using AED - take the decrypted call, analyze it and compose a call to the slave APIs the salve API's accept calls that are also encrypted using same KEY and base64_encoded - the slave API's process the call, connect to database, and other resources, and respond. - the response is also decrypted to anayse its result and finally - respond to the original caller with the response. this is taking too long, and we want to work with an experienced LARAVEL developer to optimze the time it takes and produce a faster communication. we can remove encryption decryption between laravel and slave api's to save some processing time. we can also disable logs where it is not required to save on Disk I/O time. we need to measure original response time and enhanced response time and cut it down by some 500% Bidder must be expert in POSTMAN, and must be expert in LARAVEL. No room for beginners!