macOS has built in TFTP daemon - which is useful for developer to transfer firmware during development. Ex. if you are OpenWrt developer :)

Daemon location: /System/Library/LaunchDaemons/tftp.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "">
<plist version="1.0">

Modify TFTP service parameters

By default, TFTP folder is /private/tftpboot - feel free to use other folder. However, remember to chmod whole folder or added files with correct permission, else TFTP client can't get that file.

# chmod whole folder to 777
sudo chmod -R 777 /private/tftpboot

# add a file and also chmod 777
cp fw.bin /private/tftpboot
chmod 777 /private/tftpboot/fw.bin

Start and Stop daemon

Start daemon:

sudo launchctl load -F /System/Library/LaunchDaemons/tftp.plist

Stop daemon:

sudo launchctl unload /System/Library/LaunchDaemons/tftp.plist

Test with tftp

## Fetch file fw.bin
tftp -e
tftp> get fw.bin
Received 4979 bytes in 0.0 seconds

## In case file is not available
get fw.bin
Error code 256: File not found

Good luck!