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Share-based compensation (Details)		1 Months Ended		12 Months Ended
Share-based compensation (Details)	Jan. 01, 2021	Jun. 30, 2020 installment shares	May 31, 2019 shares	Dec. 31, 2023 installment shares	Jan. 01, 2024 shares	Jan. 01, 2023 shares	Dec. 31, 2022 shares	Jun. 27, 2022 shares
Stock option
Share-based compensation.
Shares outstanding				7,469,527			5,898,888
Employee Share Purchase Plan
Share-based compensation.
Number of shares reserved for issuance						377,258
Percentage of annual increase in reserves on total number of ordinary shares outstanding			1.00%
Number of ordinary shares reserved for issuance			215,000	1,200,413
Number of shares available for issuance			430,000
2020 Plan
Share-based compensation.
Number of shares reserved for issuance		4,773,557		693,039	1,886,294	1,493,694		750,000
Percentage of annual increase in reserves on total number of ordinary shares outstanding	5.00%
2020 Plan \| Stock option
Share-based compensation.
Shares outstanding				4,803,054
Contractual life		10 years
2020 Plan \| Stock option \| Non-employee Director
Share-based compensation.
Vesting period		3 years
Number of equal quarterly installments for vesting remaining awards \| installment				4
Service period				1 year
2020 Plan \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage		25.00%
2020 Plan \| Stock option \| Employee
Share-based compensation.
Vesting period		4 years
2020 Plan \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment		36
2020 Plan \| Restricted ordinary shares
Share-based compensation.
Vesting period				4 years
Right to receive upon vesting				1
RSUs outstanding under the 2020 Plan.				326,848			187,725
Service period				1 year
Number of quarterly installments \| installment				4
2020 Plan \| Restricted ordinary shares \| First anniversary
Share-based compensation.
Vesting Percentage				25.00%
2020 Plan \| Restricted ordinary shares \| Remaining equal installments
Share-based compensation.
Number of equal quarterly installments for vesting remaining awards \| installment				12
2019 Plan \| Stock option
Share-based compensation.
Shares outstanding				2,078,033
Contractual life				10 years
2019 Plan \| Minimum \| Stock option
Share-based compensation.
Vesting period				3 years
2019 Plan \| Maximum \| Stock option
Share-based compensation.
Vesting period				4 years
Pre-IPO Share Options and restricted shares \| Stock option \| First anniversary
Share-based compensation.
Vesting Percentage				25.00%
Pre-IPO Share Options and restricted shares \| Stock option \| Employee \| Remaining equal installments
Share-based compensation.
Number of equal monthly installments for vesting remaining awards \| installment				36