The following pseudocode works well before 0.3.3.0. But it will hang in the method pykd.attachProcess since 0.3.3.0.

pykd.initialize()
pykd.attachProcess(pid)

# do some work such as executing pykd.dbgCommand(cmd)

pykd.detachProcess(pid)

The issue can be fixed by adding the initial break in the function attachProcess in dbgeng.cpp as below

ULONG opt;
hres = g_dbgMgr->control->GetEngineOptions(&opt);
if (FAILED(hres))
    throw DbgEngException(L"IDebugControl::GetEngineOptions", hres);

opt |= DEBUG_ENGOPT_INITIAL_BREAK;
hres = g_dbgMgr->control->SetEngineOptions(opt);
if (FAILED(hres))
    throw DbgEngException(L"IDebugControl::SetEngineOptions", hres);