This is a really good idea about adding a message to your lock screen on MacOS with a note on how to contact you in the event your Mac is lost.
Run this in your terminal to allow the option of selecting install from anywhere:
sudo spctl --master-disable
If you wish to clone a repo using a set private key, you can use the following syntax to do just that and it won’t add the private key to your usual SSH settings:
ssh-agent bash -c 'ssh-add private.key; git clone firstname.lastname@example.org:user/repo.git'
A few tasks that I’ve been working on this weekend have needed public/private key pairs. The very useful phpseclib library provides the tools that you need to generate these within your application.
// Get a new RSA object and set the type, hash and comment
$rsa = new RSA;
// Actually generate the key, change 4096 for the desired number of bytes
$keys = $rsa->createKey(4096);
$keyPrivate = $keys["privatekey"];
$keyPublic = $keys["publickey"];
// Get the fingerprint for this key
$keyFingerprint = $rsa->getPublicKeyFingerprint();