How can you defend your base during speedruns?

Question

I can't get the 8 hour achievement on default settings no matter how hard I try. The problem is that biters keep leveling my base before I can get beyond blue science, and often times I don't even get past green.

My normal way to defend myself is to build a perimeter wall, however the 8 hour restriction just doesn't give you the time for that. Then there's the issue of defending mining colonies. Even if they are close enough where I can just run belts to my main base from there, there's still the issue of protecting those. I've tried setting up small arrangements of turrets to defend my base, but the biters manage to find a weakpoint and level everything I've built. I just don't see how it's possible to complete this game without a defensive wall around your entire base.

I've been thinking about just blueprinting some compact base that requires only the minimal resources, then rushing bots and using that blueprint to make them win the game for me. Of course, even if I did get such a blueprint, I would still need to survive long enough to get to bots, which requires blue science and robot frames which require quite a lot of intermediates. There just isn't any way to do it fast as best as I can tell. I have tried to watch speed runners, but I just can't mimic what they do. Besides, they never seem to have the problem with biters that I do.

As an example, in my last attempt I had this massive swarm of biters like you normally see on Death world settings (or YouTube Death world anyway) come out of nowhere and level everything except my furnaces, destroying everything including my stockpiles I had spent over an hour accumulating. I just couldn't kill them nearly fast enough. They had leveled everything in the time it took for me to kill the last one.

Clearly I need to change strategy. How can you possibly defend yourself when you don't have the time to build proper defenses?

Answer 1

I was able to get this achievement following Nefrum's guide; he's a Factorio speedrunner and (at least in the past, if not currently) held the record for the "Default Settings" category.

It took me a few times to achieve myself, but I found that dealing with the biters comes down to a few key principles:

• Use Gun Turrets
• Tech to grenades
• Use grenades to clear out nearby biter nests
• Tech to robots and landmines
• automate landmines and ignore biters for the rest of the run

The main problem I ran into was one of going too slowly -- pollution spreads over time, and if your defenses don't keep up with your research/production, you'll trigger a massive biter wave before you have your defenses in place. In other words, my production was speed-run level (because miners / furnaces are easy to set up), but my science and "sim-city" base building was not.

It might help to also just watch one of these runs to follow along with the guide. You can go 3 times slower than him and still get in under 8 hours. (I ultimately managed it in 7:16ish)