Fair value measurement - Financial assets measured at fair value (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Maximum
Debt Securities, Available-for-Sale [Line Items]
Contractual maturity term	6 months
Recurring
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 215,301	$ 136,422
Unrealized Gain	57	22
Fair Value	215,358	136,444
Recurring | Level 1 | Money market funds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	46,987	73,988
Fair Value	46,987	73,988
Recurring | Level 2 | U.S. Treasury securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	94,379	22,993
Unrealized Gain	40
Fair Value	94,419	22,993
Recurring | Level 2 | Marketable securities (U.S. treasury securities)
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	73,935	39,441
Unrealized Gain	17	22
Fair Value	$ 73,952	$ 39,463