By networking mostly and recommendations but ... there are many caveats.
For example most of the companies that searches for seniors they do not actually want seniors, they just want more experienced developers in X technology.
As you will read more topics on seniority (here on dev.to) you will see what I mean. It is a lot more then what HR think it means. If you do not have a good culture, with juniors to be mentored, fluid workflows and others most likely a senior will stay in the company's way and viceversa. You do not get a senior for its coding skills, you get one to empower other devs.
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