Adding a new team member to an existing team always introduces challenges. The introduction changes the makeup of the team, and if the team had jelled, it has to do so, again, with the new member.
Also, the new member has to learn about the team and its work. There are many tacit assumptions held within a team. It’s impossible to document them all and, even if you could, both reading such a document and keeping it up to date are daunting herculean tasks.
First, they brainstormed a list of topics that a new team member needed to know. It included things like how they used the story wall, who had what role on the team, the architecture of the system, the team working agreements, and the local Agile practices. These topics were written on index cards, one to a card. When a new team member came on board, they setup a section of wall with Backlog, In Process, and Done columns, and put the index cards in the Backlog column, in a rough approximation of the order to learn them.
Existing team members put post-it notes with their names on the cards they were prepared to help with. It was the new team member’s responsibility to work through these cards, one or a few at a time. The would take a card, put it in the In Process column, and ask the person named on the post-it to help them learn whatever the card mentioned. Sometimes this took a few minutes, and sometimes it took several days to go over the topic on a card. As each card was completed, it was moved to the Done column.
The very last card was “update the new member backlog cards.” Since the newest member had just gone through the process, they were in the best position to update the deck, adding, removing, and reordering cards as appropriate. This put the deck in the best possible shape for the next new member, while the memories were still fresh.