In [[software engineering]], '''continuous integration''' ('''CI''') is the practice of merging all developers' working copies to a shared [[Trunk (software)|mainline]] several times a day andthat triggers automated build with testing.<ref name="martinfowler" /> [[Grady Booch]] first proposed the term CI in [[Booch method|his 1991 method]],<ref>{{Cite book |last=Booch |first=Grady |url=https://books.google.com/books?id=w5VQAAAAMAAJ&q=continuous+integration+inauthor:grady+inauthor:booch |title=Object Oriented Design: With Applications |publisher=[[Benjamin Cummings]] |year=1991 |isbn=9780805300918 |page=209 |author-link=Grady Booch |access-date=18 August 2014}}</ref> although he did not advocate integrating several times a day. [[Extreme programming]] (XP) adopted the concept of CI and did advocate integrating more than once per day – perhaps as many as tens of times per day.<ref>{{Cite journal |last=Beck |first=K. |date=1999 |title=Embracing change with extreme programming |journal=Computer |volume=32 |issue=10 |pages=70–77 |doi=10.1109/2.796139 |issn=0018-9162}}</ref>
