Schedule of share capital (Details) € in Thousands	6 Months Ended
Jun. 30, 2026 EUR (€) shares
IfrsStatementLineItems [Line Items]
Share premium, beginning	€ 242,004
Share premium, ending	€ 243,297
Class A ordinary shares [member]
IfrsStatementLineItems [Line Items]
Balance (in Shares) \| shares	2,288,291
Share capital, beginning	€ 9
Share premium, beginning	€ 242,004
Number of ordinary shares, conversion warrants \| shares
Share capital, conversion warrants
Share premium, conversion warrants	€ 28
Number of ordinary shares, exercise warrants \| shares	57,428
Share capital, exercise warrants
Share premium, exercise warrants	€ 279
Number of ordinary shares, element advisory agreements \| shares	95,000
Share capital, element advisory agreements
Share premium, element advisory agreements	€ 267
Number of ordinary shares, PIPE \| shares	577,124
Share capital, PIPE	€ 2
Share premium, PIPE	€ 94
Number of ordinary shares, exercise of pre-funded warrants \| shares	208,238
Share capital, exercise of pre-funded warrants	€ 1
Share premium, exercise of pre-funded warrants	€ 400
Number of ordinary shares, exercise of service warrants \| shares	71,429
Share capital, exercise of service warrants
Share premium, exercise of service warrants	€ 225
Balance (in Shares) \| shares	3,297,510
Share capital, ending	€ 12
Share premium, ending	€ 243,297

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Number of ordinary shares exercise of prefunded warrants.

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Share capital conversion warrants.

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Share capital element advisory agreements.

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Share capital exercise of service warrants.

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Share capital exercise warrants.

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Share premium conversion warrants.

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Share premium exercise warrants.

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The nominal value of capital issued.

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