Additions

• Lwt.both (#668, Brendan Long, Jeremy Yallop).
• ppx_let support with open Lwt.Infix (#667, Brendan Long).
• Lwt_stream.of_seq (#646, Hezekiah Carty).
• Lwt_io.is_closed (#635, Andreas Garnaes).
• Lwt_unix.IO_vectors.byte_count (#645, Raphaël Proust).
• Support for higher baud rates in Lwt_unix.tcgetattr and Lwt_unix.tcsetattr (#678, Frédéric Fortier).
• Replacement functions in Lwt_main for deprecated functions based on Lwt_sequence (#660).

Bugs fixed

• OCaml 4.08 compatibility (#658).
• Stack overflow in Lwt_stream.iter_p (#432, Varun Kohli).
• Incorrect bounds check in Lwt_bytes.mincore (#627, Cédric Le Moigne).
• Lwt_bytes.mincore will not be available in future releases of OpenBSD (#663, Kenneth Westerback).
• Missing header in the Android build (#652, Justus Matthiesen).
• Build broken on MSVC (98303de, 85535f7, Dmitry Bely).
• Build broken on OpenBSD (#672, Christopher Zimmermann).
• Lwt_io.of_bytes produces a channel with inaccurate positions (#636, Nathan Rebours).
• Lwt_io._.read_int behaves incorrectly on 32-bit systems (#671, reported Dmitry Bely).
• Inaccurate locations for errors related to ;%lwt (#602, @kandu).
• (_ : t) not recognized as a catch-all pattern by the PPX (#640, Florian Angeletti).
• Race condition in Lwt_react.E.limit (#606, Avni Fatehpuria).
• Premature deallocation in Lwt_react.E.with_finaliser and Lwt_react.S.with_finaliser (#626, El-Hassan Wanas).

Miscellaneous

• New tests for Lwt_bytes, portions of Lwt_unix (#619, #621, #628, #630, #673, Cédric Le Moigne, Anurag Soni).
• Test suite improvements (#656, Dave Parfitt).
• Clarifications for documentation of Lwt.try_bind, Lwt.pick (#648, #650, Bikal Lem).
• Fixed documentation of Lwt_io.read_line (#657, Yoni Levy).
• Fixed some typos (#611, #613, Rich Neswold).