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README.md

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+# Koff
+
+Kafka consumer (group) offset tracker.
+
+### WIP
+
+Work in progress, there's plenty of stuff left to figure out. You have been 
+warned.
+
+### Usage
+
+So far it is only cable of printing parsed messages. For usage eample take a 
+look at the main command.
+
+```
+go run cmd/main.go -brokers 127.0.0.1:9092
+```
+
+### Design
+
+Starting with Kafka version 0.9 consumer offsets are stored and managed by the
+Kafka server. Internally offsets are stored in the `__consumer_offsets` topic.
+It is not designed to be used by third party software but nothing stops us from
+doing that really. 
+
+This topic is not only used to store individual consumer offsets, it also 
+contains consumer group metadata: list of group members and their subscriptions
+and assignments, leader details and plenty of other things. Given that the topic
+provides realtime updates on consumer offsets and consumer group structure and
+state, it makes it a very convenient foundation for consumer or group tracking
+and monitoring.
+
+### Licence
+
+MIT