Add WIP architecture section

doc/architecture.md

@@ -0,0 +1,54 @@
+# Architecture
+
+> This part is mostly for people who want to understand how sozu work and people who want to contribute and help them to understand the architecture.
+
+## Master/worker model
+
+### Event loop with mio
+
+> Mio provides a low-level I/O API allowing callers to receive events such as socket read/write > readiness changes.
+> Mio give a cross-platform access to the system selector, so that Linux `epoll`, Windows `IOCP`, FreeBSD/Mac OS `kqueue()`, and potentially others can all be used with the same API.
+>
+> Get more info [here](https://github.com/carllerche/mio).
+
+TODO
+
+### Commands
+
+TODO
+
+## Proxying
+
+TODO
+
+## Load balacing
+
+TODO
+
+## SSL
+
+TODO
+
+## Logging
+
+TODO
+
+# Metrics
+
+## Architecture
+
+TODO
+
+## Metrics traced back
+
+TODO
+
+## Deep dive
+
+### Buffers
+
+TODO
+
+### Channel
+
+TODO