I paid tuition for a general assembly coding boot camp to strengthen my skills in the field I currently work in (software development). Is that deductible?

Simple answer: no.  The deductibility of job expenses**, for W-2 employees, was eliminated starting in tax year 2018.

The expense may qualify for the Lifetime Learning (tuition) Credit, as long as the school was an "eligible institution".

If you are self employed, then yes it is deductible as "other expenses". Label it as training expenses.

**Under the old rules,  Educational expenses to improve your current job skills were deductible. But learning a new job was not.  Even then it was only a misc. itemized deduction subject to the 2% of AGI threshold