Hi. I am working on SUnit improvements. I open issue 19015 <https://pharo.fogbugz.com/f/cases/19015/Tests-should-never-hang-and-leave-fo...>. Slice is inbox which waits your review and feedback. I was trying to address three problems: *1) Tests should never hang. They should be always executed within time limit.* I give them 10 minutes for now to not change existing behaviour of tests. At next step it should be really reduced to ~100 milliseconds (?). Any TestCase could redefine time limit by method #defaultTimeLimit. Or it could be specified directly in test code by self timeLimit: 10 seconds (could be changed at any time of test execution). To implement this logic special watch dog process is running for given test suite to control execution time of tests. It is single process for full test suite. *2) When test completes all forked processes should be terminated.* If your tested code produced zombie processes SUnit will take care about destroying all such garbage. (it not means that you don't need to clean table in #tearDown but any code could be broken and running tests should not produce dirty system). *3) Any failures inside forked processes should not spawn debugger while running tests.* Only when we debug tests we need debugger on forked failed processes. During normal run SUnit should prevent such "background debuggers" and mark such tests as failed. To implement this behaviour SUnit will handle errors from forked processes by suspending them and collecting them in special collection. I introduce TestFailedByForkedProcess error to signal these kind of problems at the end of tests. This error is resumable and resume will opens debuggers of suspended failures (in fact it will resume suspended processes). So to debug background failures you will need extra Proceed action on debugger when TestFailedByForkedProcess is signalled. But in normal run such tests will be just failed by TestFailedByForkedProcess error. *Now details on how it is done:* I introduce special process specific variable CurrentExecutionEnvironment. It is not installed by default and as default value it returns DefaultExecutionEnvironment instance. This variable is inheritable. If your install concrete environment into process it will be installed to any child process. So value of variable is instance of ExecutionEnvironment subclasses and you can install it by: anYourExecutionEnvironment beActiveDuring: aBlock When block completes previous environment is restored. For default environment there is class side method: DefaultExecutionEnvironment beActiveDuring: aBlock And to reset current environment to default: DefaultExecutionEnvironment beActive. SUnit introduces TestExecutionEnvironment which implements all described behaviour for time limits and forked processes. To activate environment there is new method #runCaseManaged. And submitted slice uses it instead of simple runCase. TestCase>>runCaseManaged CurrentExecutionEnvironment runTestCase: self DefaultExecutionEnvironment will install new TestExecutionEnvironment and delegate processing to it. And if TestExecutionEnvironment is already active it will just process new test case. Now monkey has problem in checking slice (annoying timeout for loading). So I can't see real system impact. But it should not stop you from review :)) I think it is very important features for all our tests. And environment idea will lead to very interesting future. Best regards, Denis