So not declare it officially?
There would be no tax benefit.
It doesn't matter if you are paid in dollars, bitcoins, or bushels of rice, you still have to pay taxes.
The income tax would be calculated based on the market value of the goods or services being given as income. Everything has a value. If you don't know, estimate, and hope the IRS agrees with your estimate.
Note that this includes services too. If you fix my car and in return I paint your house for you, technically you need to pay income tax on the value of a house painting.