[clusterhacks]

You are at UCSD - surely they have co-op and internship recruiting programs on campus? When I was an undergrad (longer ago that I want to admit), I did several co-ops and a summer internship. These programs are often hiring pipelines for employers. All my job offers, even after doing a MS in CS after my BS in CS, came from companies I had worked for already as an undergrad.

Also, (and I have suffered for NOT doing this better), reach out to colleagues or even recent UCSD grads from the CS program and ask for referrals. Just be low-key about it - you aren't asking for any "big" favors or nepotism-like stuff, just maybe an internal referral to their company? I think people should do this more often. Employers often offer current employees a bonus for every hired referral so those folks may get something out of it too.

Lastly, submitting resumes online seems to often be a blackhole of nothingness. Because I'm not Mr. Professional Network I have almost always applied using online submissions to jobs and haven't always had a good response rate with that method. But my longest (and current, maybe forever) gig came from a referral from someone in my social network.

[EDIT]: I noticed one of your other comments that implies you could maybe graduate sooner rather than later. This may be a controversial idea but think about taking LONGER. Double major or really think hard about getting into some big name company internship programs.