The City of Boston’s first-ever Chief of Education has left the job, according to Mayor Marty Walsh’s press secretary, Samantha Ormsby. Rahn Dorsey’s last day was Wednesday. Officials haven’t explained the departure.

Walsh created the cabinet-level position soon after he was elected to create a “bridge between City Hall and all facets of education, from colleges and universities, to BPS, to parochial and private schools, to adult continuing education.” The role was independent of the school committee and the superintendent of Boston Public Schools.

Walsh told The Boston Globe at the time that the impetus for the job came during a fight on Beacon Hill to expand charter schools. Advocates wanted Walsh to get involved, and he wanted them to have a contact at City Hall.

Before taking the job in 2014, Dorsey was the evaluation director at the Barr Foundation, a Boston-based philanthropy that funds high school innovation, climate change solutions, and the arts, among other things.

At City Hall, Dorsey worked on some of Walsh’s more ambitious and controversial projects. Dorsey was involved in the Mayor’s attempt to create a one-stop enrollment process for traditional public schools and charters, which didn’t pan out.

Dorsey has worked on delivering Walsh’s campaign promise to provide universal pre-kindergarten in Boston. Dorsey also developed some of the early plans behind Build BPS, Walsh’s project to modernize the city’s schools by closing some buildings, consolidating others, and constructing new ones.