v3.25.4
Shareholders' equity - Disclosure of Treasury Shares (Details)
SFr / shares in Units, SFr in Thousands
 12 Months Ended
Dec. 31, 2025
CHF (SFr)
shares
SFr / shares
Dec. 31, 2024
CHF (SFr)
shares
SFr / shares
Shares Outstanding [Roll Forward]    
Shares in issue at start of period 40,363,095 36,354,297
Number of treasury shares vested under the program (in shares) (644,203) (365,309)
Number of treasury shares withheld to cover social security and tax liabilities (in shares) 95,630  
Shares in issue at end of period 40,374,641 40,363,095
Weighted average exercise price of PSU and RSU outstanding at beginning of period (in CHF per share) | SFr / shares SFr 0.10 SFr 0.10
Weighted average exercise price of PSU and RSU exercised (in CHF per share) | SFr / shares 0.10 0.10
Weighted average exercise price of PSU and RSU outstanding at end of period (in CHF per share) | SFr / shares SFr 0.10 SFr 0.10
Total TCHF value at beginning of period | SFr SFr 981  
Total TCHF value at end of period | SFr SFr 1,129 SFr 981
Treasury shares    
Shares Outstanding [Roll Forward]    
Shares in issue at start of period 3,500,000 3,500,000
Shares in issue at end of period 2,962,973 3,500,000
Weighted average exercise price of PSU and RSU outstanding at beginning of period (in CHF per share) | SFr / shares SFr 0.28  
Weighted average exercise price of PSU and RSU outstanding at end of period (in CHF per share) | SFr / shares SFr 0.38 SFr 0.28
Total TCHF value at beginning of period | SFr SFr 981  
Total TCHF value at end of period | SFr SFr 1,129 SFr 981
Treasury shares | Performance Share Units (PSU)    
Shares Outstanding [Roll Forward]    
Number of treasury shares vested under the program (in shares) (599,642)  
Number of treasury shares withheld to cover social security and tax liabilities (in shares) 88,790  
Weighted average exercise price of PSU and RSU exercised (in CHF per share) | SFr / shares SFr 0.28  
Average price in CHF, Shares withheld to cover social security and tax liabilities (in CHF per share) | SFr / shares SFr 3.41  
Total TCHF value, Shares vested under the program | SFr SFr (168)  
Total TCHF value, Shares withheld to cover social security and tax liabilities | SFr SFr 303  
Treasury shares | Restricted share units    
Shares Outstanding [Roll Forward]    
Number of treasury shares vested under the program (in shares) (33,015)  
Number of treasury shares withheld to cover social security and tax liabilities (in shares) 6,840  
Weighted average exercise price of PSU and RSU exercised (in CHF per share) | SFr / shares SFr 0.28  
Average price in CHF, Shares withheld to cover social security and tax liabilities (in CHF per share) | SFr / shares SFr 3.28  
Total TCHF value, Shares vested under the program | SFr SFr (9)  
Total TCHF value, Shares withheld to cover social security and tax liabilities | SFr SFr 22