#bitcoin-dev is the Freenode IRC chat channel used to coordinate development of the Bitcoin protocol and Bitcoin core reference software and to discuss operational matters about the Bitcoin network. It can be reached using the Freenode web interface and there are public logs available.
Bitcoin-dev is a working channel for Bitcoin software developers and people interested in following the development and operation of the software and the network. It is not a first-tier technical support channel, general technical support questions can be asked in #bitcoin.
Discussions about alternative systems, Bitcoin companies or services, programming language debates, the far future, or otherwise of a speculative nature are strongly discouraged even when the channel is idle: For transparency and effective coordination it's important that people with an interest in Bitcoin's operation are able to read the channel history without getting flooded with off-topic banter. For this reason these topics are better discussed in other channels.