Income taxes - Pre-tax Income (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Income components
United States	$ (5,300,760)	$ (681,951)
Outside United States	3,018,662	2,069,739
(Loss) income before income taxes	$ (2,282,098)	$ 1,387,788