During August 2025, Qian Tankle worked on the scala/scala3 repository, focusing on improving code completion within the Scala 3 presentation compiler. Addressing a nuanced bug, Qian refined the completion logic for derives clauses so that only the type name is suggested, preventing the erroneous addition of square brackets when a type name is followed by @@ after derives. This targeted fix involved a precise update to the compiler’s code completion mechanism and the addition of a regression test to ensure ongoing correctness. Qian’s work demonstrated proficiency in Scala, compiler development, and test-driven engineering, delivering a focused, low-risk improvement.