Git keeps asking me for my ssh key passphrase

Once you have started the SSH agent with:

eval $(ssh-agent)

Do either:

To add your private key to it:
```
 ssh-add
```
This will ask you your passphrase just once, and then you should be allowed to push, provided that you uploaded the public key to Github.
To add and save your key permanently on macOS:
```
 ssh-add -K  
```
This will persist it after you close and re-open it by storing it in user’s keychain.

If you see a warning about deprecated flags, try the new variant:
```
 ssh-add --apple-use-keychain 
```
To add and save your key permanently on Ubuntu (or equivalent):
```
  ssh-add ~/.ssh/id_rsa
```