Contact Me

If you have any questions, advice or recommendations, please contact me via the following means.

You can

  • hire me to do freelance work
  • advertise on this website or do other forms of business cooperation
  • suggest topics to write on this blog
  • and so on.


  • This website is not for sale.
  • I don’t need a mobile app for my website.
  • I don’t sell or exchange backlinks.

For GPG Users

To send me an encrypted email, download my GPG public key.  You should verify the fingerprint of the key, which is AABE 92FA DD25 8BD5 ABE8 FC55 E1D9 B66E 74F2 C918.

If Your Emails are Rejected

To filter out spam emails, my email server performs various checks before accepting incoming emails. If you self host email server, please make sure:

  • Your email server has valid PTR record.
  • The hostname of your email server is resolved to the IP address.
  • The IP address and domain of your email server are not blacklisted by spamhaus.

The exact spam filters are documented in this post. I don’t check my mail server log every day, so make sure you have a well-configured email server. If we all conform to the standards, email spam would be easy to block.

Users of Gmail, hotmail, outlook, yahoo mail, protonmail, etc can always pass my spam filter. Don’t use or email address. I have blacklisted them.


Last updated: October 5, 2018