diff --git a/src/data/CCIntMap.mli b/src/data/CCIntMap.mli
index 4caf0d14..cd2afb00 100644
--- a/src/data/CCIntMap.mli
+++ b/src/data/CCIntMap.mli
@@ -24,7 +24,10 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *)
 
-(** {1 Map specialized for Int keys} *)
+(** {1 Map specialized for Int keys}
+
+{b status: unstable}
+@since NEXT_RELEASE *)
 
 type 'a t
 
diff --git a/src/misc/backtrack.mli b/src/misc/backtrack.mli
index 321bb444..1efba86d 100644
--- a/src/misc/backtrack.mli
+++ b/src/misc/backtrack.mli
@@ -1,4 +1,12 @@
 
+(** {1 Experiment with Backtracking Monad}
+
+Playing stuff, don't use (yet?).
+
+{b status: experimental}
+@since NEXT_RELEASE
+*)
+
 module type MONAD = sig
   type 'a t
   val return : 'a -> 'a t
diff --git a/src/unix/CCUnix.mli b/src/unix/CCUnix.mli
index 59c9958a..507cf1ca 100644
--- a/src/unix/CCUnix.mli
+++ b/src/unix/CCUnix.mli
@@ -28,6 +28,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 Some useful functions built on top of Unix.
 
+{b status: unstable}
 @since NEXT_RELEASE *)
 
 type 'a or_error = [`Ok of 'a | `Error of string]