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+# The sigsum tool
+
+The sigsum tool is used to log and verify SSH-signed checksums.  This document
+gives you a hands-on introduction to help you get started with sigsum logging
+without having to read any lengthy background.
+
+## Prerequisites
+
+You will need:
+
+  - [Go][], at least version 1.15. 
+    Check version with `go version`.
+  - `ssh-keygen`, at least [OpenSSH release 8.9][].
+     Check version with `sshd -v`.
+
+[OpenSSH release 8.9]: https://www.openssh.com/txt/release-8.9
+[Go]: https://go.dev/doc/install
+
+You may want somewhere to place the data associated with your signed checksums.
+Examples include a public git repository or a web server.  This is optional.  We
+will use [git.sigsum.org/testing/tree/data][] for demo purposes.
+
+[git.sigsum.org/testing/tree/data]: https://git.sigsum.org/testing/tree/data.
+
+## Install
+
+    $ go install git.sigsum.org/sigsum-go/cmd/sigsum@latest
+    $ sigsum help
+    ...
+
+## Getting started
+
+docdoc
+
+## Further reading
+
+  - Introductory blog post on [SSH signing][] by Andrew Ayer
+  - Sigsum logging [design document][] and [api specification][]
+  - How sigsum logs can be operated in a [primary-secondary mode][]
+
+[SSH signing]: https://www.agwa.name/blog/post/ssh_signatures
+[design document]: https://git.sigsum.org/sigsum/tree/doc/design.md
+[api specification]: https://git.sigsum.org/sigsum/tree/doc/api.md
+[primary-secondary mode]: https://git.sigsum.org/log-go/tree/doc/design.md