v3.25.4
Stock-based compensation - Fair value input (Details) - Employee Stock Option
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Stock-based compensation    
Expected volatility, minimum 95.00% 91.00%
Expected volatility, maximum 96.00% 96.00%
Risk-free interest rate, Minimum 3.80% 3.60%
Risk-free interest rate, Maximum 4.30% 4.50%
Dividend yield 0.00% 0.00%
Minimum    
Stock-based compensation    
Expected term 5 years 3 months 18 days 5 years 3 months 18 days
Maximum    
Stock-based compensation    
Expected term 6 years 6 years 1 month 6 days