"project lead" is a possibility, but that would more be a person.

"main contractor" is used also in software development, a "contractor" could be operating in any sector.

1. b) Hiring contractor/s:
The development of a new system requires a significant investment of time, effort, and money. It is in the best interests of UNESCO that its personnel should ensure that proper systems are developed, the use of the Organisation assets are controlled, and the system achieves its design objectives.
Depending on the scope of the project to be developed, it would initially be advisable for UNESCO to carry out a preliminary feasibility study. This study may be carried out in-house by qualified personnel in the Information Technology field (which would not require writing a contract) or by an external reliable consulting firm, here called main contractor, with proven experience in business management as well as being technically conversant with Information Technology matters. The objective of this preliminary study would be the following:
(a) To advise/indicate the purchase of a commercial software package available in
the market to do the work needed - Or,
(b) To prepare a master plan regarding the project to be developed;
(c) To provide an accurate estimate of the full cost of the project;
(d) To assure that adequate resources and funding are available to develop and
implement the project;
(e) To obtain both Management commitment and approval.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c... page 10

Nothing wrong with "contractor" used outside of the construction industry.