Net loss per share - Basic and diluted net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net loss	$ (28,347)	$ (14,678)	$ (82,739)	$ (48,782)
Denominator:
Weighted average ordinary shares outstanding, basic	29,676,021	25,039,990	29,643,502	23,719,124
Weighted average ordinary shares outstanding, diluted	29,676,021	25,039,990	29,643,502	23,719,124
Net loss per share, basic	$ (0.96)	$ (0.59)	$ (2.79)	$ (2.06)
Net loss per share, diluted	$ (0.96)	$ (0.59)	$ (2.79)	$ (2.06)