- Director, The Ben-Zvi Institute for the Study of Jewish Communities in the East
- Head The Center for the Study of Jewish Languages and Literatures, The Hebrew University
- Founding co-Editor-in-Chief, Journal of Jewish Languages, Brill Academic Publishers
- Co-editor, Massorot: Studies in Language Traditions and Jewish Languages
- Editor (Languages and Linguistics),Encyclopedia of Jews in the Islamic World (Chief editor: N. A. Stillman), Brill Academic Publishers, 2nd edition
- Full Member, and a member of the Executive Committee, The Academy of the Hebrew Language
Rabbinic Hebrew in Karaite writings; North-African Judeo-Arabic; Judeo-Arabic translations of the Bible and of post-biblical literature; Medieval Hebrew; Hebrew in Algeria in the 19th-20th centuries; The contact between Hebrew and Arabic in the Middle Ages.
B.A Summa Cum Laude, The Hebrew University of Jerusalem, Hebrew language & Arabic language and literature.
M.A Summa Cum Laude, The Hebrew University of Jerusalem, Jewish Languages (Thesis: "The Phonology and Topics in the Morphology of a Judeo-Arabic Translation of the Book of Psalms from Constantine (Algeria)").
PhD, The Hebrew University of Jerusalem, Hebrew Language (Thesis: "Rabbinic Hebrew Handed-Down in Karaite Literature")
Post-doctorate, Harvard University, Cambridge, MA, The Center for Jewish Studies.
Post-doctorate, The Hebrew University, Eliezer Ben Yehuda Fellow for the History of Hebrew
2005 - Shelomo Dov Goitein Prize for Genizah Studies
2011 - Michelle and Robert Asaraf Prize by the Academy of Hebrew Langauge
2013 - Ben-Zvi Award for Resaerch of Jewish Communities in the East
2013 - Polonsky Prize for Creativity and Originality in the Humanistic Disciplines (first prize)