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+title = "Implementation Overview"
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+
+The following design aspects may convince you that `zrepl` is superior to a hacked-together shell script solution.
+
+## Language
+
+`zrepl` is written in Go, a real programming language with type safety,
+reasonable performance, testing infrastructure and an (opinionated) idea of
+software engineering.
+
+* key parts & algorithms of `zrepl` are covered by unit tests
+* zrepl is noticably faster than comparable shell scripts
+
+
+## RPC protocol
+
+While it is tempting to just issue a few `ssh remote 'zfs send ...' | zfs recv`, this has a number of drawbacks:
+
+* The snapshot streams need to be compatible.
+* Communication is still unidirectional. Thus, you will most likely
+    * either not take advantage of features such as *compressed send & recv*
+    * or issue additional `ssh` commands in advance to figure out what features are supported on the other side.
+* Advanced logic in shell scripts is ugly to read, poorly testable and a pain to maintain.
+
+`zrepl` takes a different approach:
+
+* Define an RPC protocol.
+* Establish an encrypted, authenticated, bidirectional communication channel...
+* ... with `zrepl` running at both ends of it.
+
+ This has several obvious benefits:
+
+* No blank root shell access is given to the other side.
+* Instead, access control lists (ACLs) are used to grant permissions to *authenticated* peers. 
+* The transport mechanism is decoupled from the remaining logic, keeping it extensible (e.g. TCP+TLS)
+
+{{% panel %}}
+Currently, the bidirectional communication channel is multiplexed on top of a single SSH connection.
+Local replication is of course handled efficiently via simple method calls
+See TODO for details.
+{{% / panel %}}
+