diff --git a/src/no_runner.ml b/src/immediate_runner.ml
similarity index 100%
rename from src/no_runner.ml
rename to src/immediate_runner.ml
diff --git a/src/immediate_runner.mli b/src/immediate_runner.mli
new file mode 100644
index 00000000..ed017eba
--- /dev/null
+++ b/src/immediate_runner.mli
@@ -0,0 +1,20 @@
+(** Runner that runs tasks immediately in the caller thread.
+
+    Whenever a task is submitted to this runner via [Runner.run_async r task],
+    the task is run immediately in the caller thread as [task()].
+    There are no background threads, no resource, this is just a trivial
+    implementation of the interface.
+
+    This can be useful when an implementation needs a runner, but there isn't
+    enough work to justify starting an actual full thread pool.
+
+    Another situation is when threads cannot be used at all (e.g. because you
+    plan to call [Unix.fork] later).
+
+    @since NEXT_RELEASE
+*)
+
+include module type of Runner
+
+val runner : t
+(** The trivial runner that actually runs tasks at the calling point. *)
diff --git a/src/moonpool.ml b/src/moonpool.ml
index 498a9fb3..cb82f668 100644
--- a/src/moonpool.ml
+++ b/src/moonpool.ml
@@ -13,7 +13,7 @@ module Fifo_pool = Fifo_pool
 module Fork_join = Fork_join
 module Fut = Fut
 module Lock = Lock
-module No_runner = No_runner
+module Immediate_runner = Immediate_runner
 module Pool = Fifo_pool
 module Runner = Runner
 module Thread_local_storage = Thread_local_storage
diff --git a/src/moonpool.mli b/src/moonpool.mli
index 05b8649c..40b78891 100644
--- a/src/moonpool.mli
+++ b/src/moonpool.mli
@@ -12,7 +12,7 @@
 module Ws_pool = Ws_pool
 module Fifo_pool = Fifo_pool
 module Runner = Runner
-module No_runner = No_runner
+module Immediate_runner = Immediate_runner
 
 module Pool = Fifo_pool
 [@@deprecated "use Fifo_pool or Ws_pool to be more explicit"]
diff --git a/src/no_runner.mli b/src/no_runner.mli
deleted file mode 100644
index 2c295adc..00000000
--- a/src/no_runner.mli
+++ /dev/null
@@ -1,6 +0,0 @@
-(** Runner that runs in the caller, not in the background. *)
-
-include module type of Runner
-
-val runner : t
-(** The trivial runner that actually runs tasks at the calling point. *)