Automate wall, ammo, and turret production early. Rush to lasers, nucelar power, and bots once you build up a little bit. Use double layers or thicker, and belts to feed ammo. Covers early but scales poorly.

Late game, once you scaled up, make copy pastable wall segments with flame, laser turrets, pipeing, and a robot port. Paste your walls and let the robots build them.

Once you have enough bots and materials you base can rebuild itself and repair the defences.