Hi miwara18,
Hope you are hale & healthy.
I have gone through your project Crypto Exchange
I am a full stack developer with strong knowledge of your required skills Cryptography, Java, JSON, PHP and have developed similar thing.
Kindly have a look at my freelancer work and can share more work at the time of interview.
I would be pleased to set up quick online discussion with you to get to know more about your project so I would really appreciate if you can revert back with your availability.
I can do this within your budget too €1500 - €3000 EUR
Looking forward to hear from you soon.
Kind Regards,
Mmadi