Summary of significant accounting policies - Potentially dilutive securities (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Potentially dilutive securities
Total shares of common stock equivalents	610,225	310,197
Convertible preferred stock (as converted)
Potentially dilutive securities
Total shares of common stock equivalents	28,112
Options to purchase common stock
Potentially dilutive securities
Total shares of common stock equivalents	551,886	287,281
Unvested restricted stock units
Potentially dilutive securities
Total shares of common stock equivalents	30,227	22,916