Appending to a remote file with remote-evaluated timestamps: an unquoted heredoc inside ssh '...'

To append a templated block to a file on a remote host, with dates computed on the remote side (its clock and TZ), put the whole heredoc inside the single-quoted ssh command and leave the delimiter unquoted:

ssh host 'D=$(TZ=America/Chicago date -d "+12 min" +%H:%M); cat >> ~/log.md <<EOF
## $(TZ=America/Chicago date +%H:%M) | deadline $D
- body text
EOF'

- The outer single quotes stop the local shell from expanding anything. The remote shell expands $D and $(date) because the remote delimiter is unquoted. - Apostrophes in the body have to leave the single quotes: write '"'"' (end quote, a double-quoted apostrophe, reopen quote). - If the body needs no remote expansion, pipe a quoted local heredoc instead, which avoids all the escaping: ssh host 'cat >> ~/log.md' <<'EOF' ... EOF. - date -d is GNU-only. If the remote is macOS/BSD, use date -v+12M.