Christian Sommer

• csom@csail.mit.edu, www.chsommer.com

Software Engineer at Google, Zurich, Switzerland (2025–present)

• Google Maps

Engineering Manager at Apple, Cupertino, CA (2016–2020) and Zurich, Switzerland (2020–2024)

• Apple Maps Traffic (Speed Profiles, Live Traffic, Incidents)
• Fast Map Matching with Vertex-Monotone Frechet Distance (ATMOS 2021)

Software Engineer at Apple, Cupertino, CA (2012–2016)

• Apple Maps Routing (Driving and Walking Directions, Turn-by-Turn Navigation)
• Traffic-Aware Routing in Road Networks (ICDE 2018)
• On Balanced Separators in Road Networks (SEA 2015)

Postdoctoral Fellow at MIT, Cambridge, MA (2010–2012)

• Structured Recursive Separator Decompositions for Planar Graphs in Linear Time (STOC 2013)
• Exact Distance Oracles for Planar Graphs (SODA 2012)
• Teaching: 6.889 Algorithms for Planar Graphs and Beyond (with video lectures)

PhD in Computer Science at the University of Tokyo, Japan (2007–2010)

• Dean's Award for PhD Thesis Approximate Shortest Path and Distance Queries in Networks
• Shortest-Path Queries in Static Networks (ACM Computing Surveys)
• Distance Oracles for Sparse Graphs (FOCS 2009)

MSc in Computer Science at ETH Zurich, Switzerland (2002–2006)