diff --git a/gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp b/gtsam/nonlinear/tests/testIncrementalFixedLagSmoother.cpp
similarity index 100%
rename from gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp
rename to gtsam/nonlinear/tests/testIncrementalFixedLagSmoother.cpp