https://community.dynatrace.com/t5/Developer-Q-A-Forum/Add-isolatedModules/m-p/226861#M587 <P>I'll let the team know about this and then we'll update the docs if necessary.&nbsp;</P> Fri, 27 Oct 2023 13:59:37 GMT imsingh 2023-10-27T13:59:37Z https://community.dynatrace.com/t5/Developer-Q-A-Forum/Add-isolatedModules/m-p/226674#M586 <P>Right now documentation suggest fields like this in the jest.config:&nbsp;<A href="https://developer.dynatrace.com/develop/testing/unit-tests/#handling-style-imports" target="_self">link</A>&nbsp;<BR /><BR /></P><DIV><PRE>transform<SPAN>: </SPAN><SPAN>{<BR /></SPAN> <SPAN>".(css|scss|sass|less)$"</SPAN><SPAN>: </SPAN><SPAN>"&lt;rootDir&gt;/style-mock.ts"</SPAN><SPAN>,</SPAN><SPAN><BR /></SPAN><SPAN>},</SPAN></PRE><P>I suggest to add another transform:</P><DIV><PRE><SPAN>"^.+</SPAN><SPAN>\\</SPAN><SPAN>.(t|j)sx?$"</SPAN><SPAN>: </SPAN><SPAN>[</SPAN><SPAN>"ts-jest"</SPAN><SPAN>, { </SPAN>isolatedModules<SPAN>: true </SPAN><SPAN>}],</SPAN></PRE></DIV></DIV><P>&nbsp;</P><P>&nbsp;</P><P>It might sharply decrease the execution time of jest tests.<BR /><BR />In our case, this change reduces execution time from 20-40s* to 10s (34 test suites, 140 tests on Apple m1 chip)<BR /><BR />* 40s only in case when jest runs tests without starting from the slowest one. Usually it takes 20-25s</P> Thu, 26 Oct 2023 09:14:33 GMT https://community.dynatrace.com/t5/Developer-Q-A-Forum/Add-isolatedModules/m-p/226674#M586 beigert 2023-10-26T09:14:33Z https://community.dynatrace.com/t5/Developer-Q-A-Forum/Add-isolatedModules/m-p/226861#M587 <P>I'll let the team know about this and then we'll update the docs if necessary.&nbsp;</P> Fri, 27 Oct 2023 13:59:37 GMT https://community.dynatrace.com/t5/Developer-Q-A-Forum/Add-isolatedModules/m-p/226861#M587 imsingh 2023-10-27T13:59:37Z