diff --git a/Makefile.am b/Makefile.am
index 5dccd82b..2d5c7691 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,5 @@
 # Makefile.am - top level
-# Copyright (C) 2018, 2019, 2020 Michael L. Gran
+# Copyright (C) 2018, 2019, 2020, 2021 Michael L. Gran
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -373,6 +373,7 @@ TESTS = \
   test/oop.scm \
   test/value.scm \
   test/flags.scm \
+  test/task.scm \
   test/type.scm \
   test/signals.scm \
   test/logging.scm \
diff --git a/test/task.scm b/test/task.scm
new file mode 100644
index 00000000..3d140d03
--- /dev/null
+++ b/test/task.scm
@@ -0,0 +1,125 @@
+(use-modules (gi) (gi types) (gi repository)
+             (oop goops)
+             (system foreign)
+             (ice-9 format)
+             (srfi srfi-64))
+
+(use-typelibs ("GLib" "2.0") ("Gio" "2.0"))
+
+(test-begin "task")
+
+(define loop #f)
+
+(test-assert "new MainLoop"
+  (begin (set! loop (main-loop:new #f #t))
+         (is-a? loop <GMainLoop>)))
+
+(test-assert "create a task"
+  (let ((T (task:new)))
+    (task:is-valid? T)))
+
+(test-assert "create a task acting on an object"
+  (let* ((obj (make <GObject>))
+         (T (task:new obj)))
+    (task:is-valid? T obj)))
+
+(test-assert "create a task with a Cancellable"
+  (let* ((kancel (cancellable:new))
+         (T (task:new #f kancel)))
+    (task:is-valid? T)))
+
+(test-equal "return pointer from a task"
+  #x1234
+  (let ((T (task:new)))
+    (idle-add PRIORITY_DEFAULT
+              (lambda (data)
+                (return-pointer T (make-pointer #x1234))
+                (quit loop)
+                #f))
+    (main-loop:run loop)
+    (pointer-address (propagate-pointer T))))
+
+(test-equal "return pointer from a task via its callback"
+  #x1234
+  (let* ((return-value #f)
+         (iter 0)
+         (T (task:new
+             #f
+             #f
+             (lambda (source task data)
+               (set! return-value (pointer-address (propagate-pointer task)))))))
+    (idle-add PRIORITY_DEFAULT
+              (lambda (data)
+                (when (zero? iter)
+                  (return-pointer T (make-pointer #x1234)))
+                (set! iter (1+ iter))
+                (if return-value
+                    (begin
+                      (quit loop)
+                      #f)
+                    ;; else
+                    #t)))
+    (main-loop:run loop)
+    return-value))
+
+(test-equal "return pointer from a task run in thread"
+  #x1234
+  (let ((T (task:new (make <GObject>))))
+    (run-in-thread T
+                   (lambda (task source data kancel)
+                     (return-pointer T (make-pointer #x1234))))
+    (idle-add PRIORITY_DEFAULT
+              (lambda (data)
+                (if (get-completed? T)
+                    (begin
+                      (quit loop)
+                      #f)
+                    ;; else
+                    #t)))
+    (main-loop:run loop)
+    (pointer-address (propagate-pointer T))))
+
+(test-assert "cancel task and check cancellable"
+  (let* ((kancel (cancellable:new))
+         (T (task:new #f kancel)))
+    (idle-add PRIORITY_DEFAULT
+              (lambda (data)
+                (cancel kancel)
+                (quit loop)
+                #f))
+    (main-loop:run loop)
+    (is-cancelled? kancel)))
+
+(test-assert "cancel task and check task was cancelled"
+  (let* ((kancel (cancellable:new))
+         (T (task:new #f kancel)))
+    (idle-add PRIORITY_DEFAULT
+              (lambda (data)
+                (cancel kancel)
+                (quit loop)
+                #f))
+    (main-loop:run loop)
+    (return-error-if-cancelled? T)))
+
+
+(test-equal "attach pointer to a task and retrieve"
+      #xBEEF
+      (let ((T (task:new)))
+        (set-task-data T (make-pointer #xBEEF))
+        (pointer-address (get-task-data T))))
+
+(test-assert "attach pointer and DestroyNotify to a task"
+  (let ((T (task:new))
+        (destroyed #f))
+    ;; Add some data, plus a lambda to be called when the data
+    ;; is overwritten.
+    (set-task-data T
+                   (make-pointer #xFACE)
+                   (lambda (ptr)
+                     (set! destroyed #t)))
+    ;; Overwrite the data.
+    (set-task-data T
+                   (make-pointer #xD00D))
+    destroyed))
+
+(test-end "task")