The test execution is noticeably slower after upgrade

Updated on Jan 27, 2026

Environment

Product	Version
Progress® Telerik® JustMock	2023.3.1011.155

Description

Tests that reference a lot of 3rd party libraries may experience degraded performance after upgrading to JustMock 2023.3.1011.155.

Solution

Set an environment variable called JUSTMOCK_NEWOBJ_INTERCEPTION_ON_OVERWRITE_ENABLED to 0 before test execution. The easiest way to set this environment variable is to use runsettings. Here is an example:

xml

<RunSettings>
    <RunConfiguration>
        <EnvironmentVariables>
        <JUSTMOCK_NEWOBJ_INTERCEPTION_ON_OVERWRITE_ENABLED>0</JUSTMOCK_NEWOBJ_INTERCEPTION_ON_OVERWRITE_ENABLED>
        </EnvironmentVariables>
    </RunConfiguration>
</RunSettings>