• [File] Allow :raw option in File.exists?/2, File.regular?/2 and File.dir?/2
• [Kernel] Do not propagate counters to variables in quote inside another quote
• [List] Add List.myers_difference/3
• [Registry] Allow associating a value on :via tuple
• [String] Add String.bag_distance/2

• [ExUnit.Assertions] Show last n messages from mailbox on assert_receive fail

• [mix compile.protocols] Reconsolidate protocols if local deps is stale
• [mix deps] Mark dependencies with different :system_env as diverged

• [ExUnit.Assertions] Consistently expand patterns and guards in assertions

• [Enum] Passing a non-empty list to Enum.into/2 was inconsistent with maps and is deprecated in favor of Kernel.++/2 or Keyword.merge/2
• [Inspect.Algebra] surround/3 is deprecated in favor of Inspect.Algebra.concat/2 and Inspect.Algebra.nest/2
• [Inspect.Algebra] surround_many/6 is deprecated in favor of container_doc/6
• [Kernel] Passing a non-empty list as :into in for comprehensions was inconsistent with maps and is deprecated in favor of Kernel.++/2 or Keyword.merge/2
• [Kernel.ParallelCompiler] files/2 is deprecated in favor of compile/2
• [Kernel.ParallelCompiler] files_to_path/2 is deprecated in favor of compile_to_path/2
• [Kernel.ParallelRequire] files/2 is deprecated in favor of Kernel.ParallelCompiler.require/2
• [System] :seconds, :milliseconds, etc as time units is deprecated in favor of :second, :millisecond, etc

• [mix compile.erlang] Returning {:ok, contents} or :error as the callback in Mix.Compilers.Erlang.compile/6 is deprecated in favor of returning {:ok, contents, warnings} or {:error, errors, warnings}

The CHANGELOG for v1.7 releases can be found in the v1.7 branch.