DSS

Judgement

What it is

Building block

What it does

The European Commission's Java library for creating, extending and validating XAdES, CAdES, PAdES, JAdES and ASiC electronic signatures.

Adopt it when

You build software that must produce or validate eIDAS-compliant signatures in the EU.

Watch out

Large and complex API; issues are tracked in the Commission's JIRA rather than GitHub.

Ready for

Production-ready

Runs as

Library

Built with

Java

How established

Established: started 11 years ago, latest release 6.5.1.

What the license allows

You can use it inside a product you sell; changes you make to its own files must be shared.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: DSS → JDK → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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