Even if this is a side gig, then if you turn a profit in 3 years out of 5 (and/or some other details...) then you treat it as a business and your expenses are deducted from your gross income. The IRS cracks down on doctors taking business losses from their horse farms, I don't think that's the case here.
The only difference is the earned income tax credit, which is a US credit to encourage people to get off welfare and work, basically it pays your income taxes (and WAY more in some cases) for lower income working people. The amount actually goes UP with INCOME going UP at the very bottom of the scale, which is why you want to be at least in the MIDDLE of the range. Especially if you are at risk of being out of the range next year with more profit.
Farmers and Fisherman are given ways to even out income so they're not hit like this. As a dirt contractor, you have to do the same thing within the rules allowed you. That might be waiting to pay for a portion of the repairs until this year, or capitalizing the repairs and spreading the depreciation out (treating the repairs like improvements, or a purchase of a new machine). Depreciation stinks, but it might be worth it in this case as a last resort.
You really need to know your tax situation and how it affects your REAL bottom line, how much you get to keep. I promise that Barry, Donald, Bill and Hillary know EXACTLY what they are doing to minimize their taxes, and probably pay a much lower percentage of their income in taxes than you and I do.
Edit: just saw CM's post, exactly, accrual accounting changes things, and I think there are lots more ways that larger, more complicated corp's have to minimize income, take advantage of credits, etc etc.