Spain is putting a hash chain behind every invoice, and almost everything written about it so far has been written for accountants. This is the version for whoever has to ship it. The deadlines are January 1, 2027 for companies and July 1, 2027 for sole traders. If you read something last year that said 2026, that was true until RD-ley 15/2025 moved the whole calendar back twelve months. Software vendors have been on the hook since July 2025, which is a detail worth holding on to if you sell ...