| 
       in CHF 1 000  | 
    
       Notes  | 
    
       2022  | 
    
       2021  | 
  
| 
       Net profit  | 
    
       
  | 
    
       3 820  | 
    
       7 482  | 
  
| 
       Depreciation  | 
    
       (5)  | 
    
       10 365  | 
    
       9 729  | 
  
| 
       Impairment  | 
    
       (5)  | 
    
       -  | 
    
       184  | 
  
| 
       Amortization  | 
    
       (6)  | 
    
       9 676  | 
    
       1 005  | 
  
| 
       Interest income  | 
    
       (22)  | 
    
       –84  | 
    
       –4  | 
  
| 
       Interest expenses  | 
    
       (22)  | 
    
       3 088  | 
    
       1 042  | 
  
| 
       Tax expenses  | 
    
       (11)  | 
    
       3 873  | 
    
       2 728  | 
  
| 
       Change in provisions  | 
    
       
  | 
    
       –770  | 
    
       1 228  | 
  
| 
       Change in other non-current assets  | 
    
       
  | 
    
       –560  | 
    
       -  | 
  
| 
       Other non-cash-items  | 
    
       
  | 
    
       –448  | 
    
       –35  | 
  
| 
       Subtotal before working capital changes  | 
    
       
  | 
    
       28 960  | 
    
       23 359  | 
  
| 
       Change in inventories  | 
    
       
  | 
    
       –31 652  | 
    
       –20 896  | 
  
| 
       Change in trade accounts receivable  | 
    
       
  | 
    
       –5 876  | 
    
       –7 044  | 
  
| 
       Change in other current assets  | 
    
       
  | 
    
       1 233  | 
    
       –1 445  | 
  
| 
       Change in trade accounts payable  | 
    
       
  | 
    
       116  | 
    
       6 281  | 
  
| 
       Change in other current liabilities  | 
    
       
  | 
    
       3 138  | 
    
       12 780  | 
  
| 
       Change in working capital  | 
    
       
  | 
    
       –33 041  | 
    
       –10 324  | 
  
| 
       Income tax paid  | 
    
       
  | 
    
       –2 879  | 
    
       –3 055  | 
  
| 
       Interest paid  | 
    
       
  | 
    
       –3 114  | 
    
       –750  | 
  
| 
       Interest received  | 
    
       
  | 
    
       17  | 
    
       4  | 
  
| 
       Net cash (used in) / from operating activities  | 
    
       
  | 
    
       –10 057  | 
    
       9 234  | 
  
| 
       Purchase of property, plant and equipment  | 
    
       
  | 
    
       –11 206  | 
    
       –7 790  | 
  
| 
       Proceeds from sale of property, plant and equipment  | 
    
       
  | 
    
       32  | 
    
       1  | 
  
| 
       Purchase of intangible assets  | 
    
       (6)  | 
    
       –225  | 
    
       –262  | 
  
| 
       Acquisition of subsidiaries, net of cash acquired  | 
    
       
  | 
    
       –19 645  | 
    
       –45 006  | 
  
| 
       Net cash used in investing activities  | 
    
       
  | 
    
       –31 044  | 
    
       –53 057  | 
  
| 
       Purchase of treasury shares  | 
    
       (18)  | 
    
       –45  | 
    
       -  | 
  
| 
       Issuance of mandatory convertible note  | 
    
       
  | 
    
       59 069  | 
    
       -  | 
  
| 
       Payment to shareholders from capital contribution reserves  | 
    
       (17)  | 
    
       -  | 
    
       –2 902  | 
  
| 
       Repayment of finance lease liabilities  | 
    
       
  | 
    
       –600  | 
    
       –38  | 
  
| 
       Proceeds from borrowings short-term  | 
    
       
  | 
    
       2 402  | 
    
       502  | 
  
| 
       Proceeds from borrowings long term  | 
    
       
  | 
    
       13 286  | 
    
       76 534  | 
  
| 
       Repayment of borrowings short-term  | 
    
       
  | 
    
       –25 165  | 
    
       –3 304  | 
  
| 
       Net cash from financing activities  | 
    
       
  | 
    
       48 947  | 
    
       70 792  | 
  
| 
       Currency translation effects  | 
    
       
  | 
    
       –1 152  | 
    
       –1 307  | 
  
| 
       Net increase in cash and cash equivalents  | 
    
       
  | 
    
       6 694  | 
    
       25 662  | 
  
| 
       Cash and cash equivalents at the beginning of the period  | 
    
       (9)  | 
    
       68 797  | 
    
       43 135  | 
  
| 
       Cash and cash equivalents at the end of the period  | 
    
       (9)  | 
    
       75 491  | 
    
       68 797  |