The Indianapolis Colts have made a number of changes to their coaching staff in the past week, as they have already hired a new defensive coordinator and are looking for a new safeties coach, secondary coach, linebackers coach, tight ends coach, running backs coach, and strength and conditioning coach. According to FOX Sports, they have also been looking for a new offensive line coach, as it appears one of the coaches has an expiring contract and will not be retained (it's unknown which one, and FOX's Mike Garafolo noted that the other might be fired anyway).
FOX Sports' Alex Marvez noted a few days ago that the Colts were interviewing three people for the opening, and it appears they have decided on one of them: according to Marvez, the Colts have offered Chris Foerster their offensive line coach position.
That's all the details that we have at the moment, as it remains unclear whether Foerster will accept the offer or not, as well as what the Colts will do regarding other people currently at the position (Joe Gilbert and Hal Hunter handled the duties in 2015). So there's nothing official yet, but Marvez is reporting that the Colts have offered the job to Foerster after interviewing him.
Foerster spent the 2015 season as the offensive line coach of the San Francisco 49ers under Jim Tomsula, but with the head coach fired the staff will also likely be out. He has plenty of coaching experience, however, as before his time in San Francisco he was the offensive line coach for the Washington Redskins for five seasons (2010-2014), the San Francisco 49ers for two seasons (2008-2009), and the Ravens for three seasons (2005-2007). In 2004, he was the offensive coordinator for the Miami Dolphins, while before that he served under Tony Dungy's staff for eight seasons: first as the offensive line coach for the Tampa Bay Buccaneers (1996-2001) and then as the tight ends coach for the Indianapolis Colts (2002-2003). Before that, he was the assistant offensive line coach and the tight ends coach for the Minnesota Vikings for three seasons (1994-1995).