Keeping members of a community in sync is a resource-consuming task. For example, many security researchers have to spend the whole day on IMs in order not to miss a single threat.
As a former creator of an open source community, I have also been working in the infosec community for several years and have learned some effective approaches from open source communities.
During the operation of an open source community, we found that old-school members tend to use e-mail, NNTP, RSS, etc, which have a long history yet are still effective. I will briefly introduce the story of "The Email Client -- PINE" that has survived since 1992. Yes, Linus Torvalds uses it. I have been using it for the past three years and have provided some patches for it.
However, new members tend to use a variety of fancy instant messaging tools. In order to both encourage new members and not to offend old-fashioned members, we created a bot that forwards messages between IM and old-school tools.
According to Dunbar's number (the rule of 150), the difficulty of establishing close ties between members is greatly increased when the community grows bigger. Plus, there are tens of thousands of messages every day, making it difficult for members to keep up with every new idea in the community. Our recommendation is to provide a semi-automatic or fully automated summary service, as the services provided by LLVM Weekly and LWN, periodically publish the abstracts of the discussions within the community to the blog.
Interestingly, we found that the popular sticker culture is not conducive to community discussion -- it is too large while providing no information. This will discourage people from posting valuable information. We made a bot to delete them. This policy has achieved surprisingly good results.
For offline events, we developed a set of Danmaku tools -- a floating left-to-right comment -- both software and hardware to make it easy for audiences to comment in real time, right on the big screen. The interactive experience is very inspiring. We also find it awesome to record the event to publish in our podcast.
It is worth mentioning that setting up some barriers to entry is beneficial to the expansion of the community. We will explain why.
These approaches have been proven to be effective during the operation of an 8-year-old open source community. I hope those would be some inspiration for the infosec community to help keep every member in sync without consuming too much energy.