v3.26.1
Stock-based compensation - Assumptions and stock based compensation expense (Details)
12 Months Ended
Dec. 31, 2025
USD ($)
Y
Dec. 31, 2024
USD ($)
Y
Stock-based compensation    
Expected life of stock options | Y 10 10
Expected weighted average volatility 84.00% 84.00%
Expected dividend yield 0.00% 0.00%
Weighted average risk-free interest rate 3.10% 3.03%
Weighted average fair value of stock options granted in the year $ 0.44 $ 0.44
Stock-based compensation expense $ 3,235,000 $ 1,641,000