diff --git a/ce2/js/src/main/scala/munit/CatsEffectSuitePlatform.scala b/ce2/js/src/main/scala/munit/CatsEffectSuitePlatform.scala
new file mode 100644
index 0000000..700f522
--- /dev/null
+++ b/ce2/js/src/main/scala/munit/CatsEffectSuitePlatform.scala
@@ -0,0 +1,25 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.IO
+
+private[munit] trait CatsEffectSuitePlatform { self: CatsEffectSuite =>
+
+  private[munit] def unsafeRunSyncOrForget[A](ioa: IO[A]): Unit = ioa.unsafeRunAsyncAndForget()
+
+}
diff --git a/ce2/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala b/ce2/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala
new file mode 100644
index 0000000..f680555
--- /dev/null
+++ b/ce2/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.IO
+
+private[munit] trait CatsEffectSuitePlatform { self: CatsEffectSuite =>
+
+  private[munit] def unsafeRunSyncOrForget[A](ioa: IO[A]): Unit = {
+    ioa.unsafeRunSync()
+    ()
+  }
+
+}
diff --git a/ce2/shared/src/main/scala/munit/CatsEffectSuite.scala b/ce2/shared/src/main/scala/munit/CatsEffectSuite.scala
index 265f80c..cfe21c0 100644
--- a/ce2/shared/src/main/scala/munit/CatsEffectSuite.scala
+++ b/ce2/shared/src/main/scala/munit/CatsEffectSuite.scala
@@ -22,6 +22,7 @@ import scala.concurrent.{Future, ExecutionContext}
 
 abstract class CatsEffectSuite
     extends FunSuite
+    with CatsEffectSuitePlatform
     with CatsEffectAssertions
     with CatsEffectFixtures
     with CatsEffectFunFixtures {
@@ -48,3 +49,8 @@ abstract class CatsEffectSuite
     )
 
 }
+
+object CatsEffectSuite {
+  private[munit] type Deferred[F[_], A] = cats.effect.concurrent.Deferred[F, A]
+  private[munit] val Deferred = cats.effect.concurrent.Deferred
+}
diff --git a/ce3/js/src/main/scala/munit/CatsEffectSuitePlatform.scala b/ce3/js/src/main/scala/munit/CatsEffectSuitePlatform.scala
new file mode 100644
index 0000000..06a7a60
--- /dev/null
+++ b/ce3/js/src/main/scala/munit/CatsEffectSuitePlatform.scala
@@ -0,0 +1,25 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.IO
+
+private[munit] trait CatsEffectSuitePlatform { self: CatsEffectSuite =>
+
+  private[munit] def unsafeRunSyncOrForget[A](ioa: IO[A]): Unit = ioa.unsafeRunAndForget()
+
+}
diff --git a/ce3/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala b/ce3/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala
new file mode 100644
index 0000000..f680555
--- /dev/null
+++ b/ce3/jvm/src/main/scala/munit/CatsEffectSuitePlatform.scala
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.IO
+
+private[munit] trait CatsEffectSuitePlatform { self: CatsEffectSuite =>
+
+  private[munit] def unsafeRunSyncOrForget[A](ioa: IO[A]): Unit = {
+    ioa.unsafeRunSync()
+    ()
+  }
+
+}
diff --git a/ce3/shared/src/main/scala/munit/CatsEffectSuite.scala b/ce3/shared/src/main/scala/munit/CatsEffectSuite.scala
index 46b0c4e..00be20b 100644
--- a/ce3/shared/src/main/scala/munit/CatsEffectSuite.scala
+++ b/ce3/shared/src/main/scala/munit/CatsEffectSuite.scala
@@ -23,6 +23,7 @@ import scala.concurrent.{ExecutionContext, Future}
 
 abstract class CatsEffectSuite
     extends FunSuite
+    with CatsEffectSuitePlatform
     with CatsEffectAssertions
     with CatsEffectFixtures
     with CatsEffectFunFixtures {
@@ -47,3 +48,8 @@ abstract class CatsEffectSuite
     )
 
 }
+
+object CatsEffectSuite {
+  private[munit] type Deferred[F[_], A] = cats.effect.kernel.Deferred[F, A]
+  private[munit] val Deferred = cats.effect.kernel.Deferred
+}
diff --git a/common/js/src/main/scala/munit/CatsEffectFixtures.scala b/common/js/src/main/scala/munit/CatsEffectFixturesPlatform.scala
similarity index 90%
rename from common/js/src/main/scala/munit/CatsEffectFixtures.scala
rename to common/js/src/main/scala/munit/CatsEffectFixturesPlatform.scala
index ba5f5ec..9a21cf3 100644
--- a/common/js/src/main/scala/munit/CatsEffectFixtures.scala
+++ b/common/js/src/main/scala/munit/CatsEffectFixturesPlatform.scala
@@ -16,4 +16,4 @@
 
 package munit
 
-trait CatsEffectFixtures { self: CatsEffectSuite => }
+trait CatsEffectFixturesPlatform { self: CatsEffectSuite => }
diff --git a/common/jvm/src/main/scala/munit/CatsEffectFixtures.scala b/common/jvm/src/main/scala/munit/CatsEffectFixturesPlatform.scala
similarity index 96%
rename from common/jvm/src/main/scala/munit/CatsEffectFixtures.scala
rename to common/jvm/src/main/scala/munit/CatsEffectFixturesPlatform.scala
index 056c776..f3f7330 100644
--- a/common/jvm/src/main/scala/munit/CatsEffectFixtures.scala
+++ b/common/jvm/src/main/scala/munit/CatsEffectFixturesPlatform.scala
@@ -18,7 +18,7 @@ package munit
 
 import cats.effect.{IO, Resource}
 
-trait CatsEffectFixtures { self: CatsEffectSuite =>
+trait CatsEffectFixturesPlatform { self: CatsEffectSuite =>
 
   object ResourceSuiteLocalFixture {
 
diff --git a/common/jvm/src/test/scala/munit/CatsEffectFixturesSpec.scala b/common/jvm/src/test/scala/munit/CatsEffectFixturesPlatformSpec.scala
similarity index 89%
rename from common/jvm/src/test/scala/munit/CatsEffectFixturesSpec.scala
rename to common/jvm/src/test/scala/munit/CatsEffectFixturesPlatformSpec.scala
index 5afc1ed..c66188b 100644
--- a/common/jvm/src/test/scala/munit/CatsEffectFixturesSpec.scala
+++ b/common/jvm/src/test/scala/munit/CatsEffectFixturesPlatformSpec.scala
@@ -17,8 +17,9 @@
 package munit
 
 import cats.effect.{IO, Resource}
+import scala.concurrent.duration._
 
-class CatsEffectFixturesSpec extends CatsEffectSuite with CatsEffectAssertions {
+class CatsEffectFixturesPlatformSpec extends CatsEffectSuite with CatsEffectAssertions {
 
   var acquired: Int = 0
   var released: Int = 0
@@ -26,12 +27,12 @@ class CatsEffectFixturesSpec extends CatsEffectSuite with CatsEffectAssertions {
   val fixture = ResourceSuiteLocalFixture(
     "fixture",
     Resource.make(
-      IO {
+      IO.sleep(1.millis) *> IO {
         acquired += 1
         ()
       }
     )(_ =>
-      IO {
+      IO.sleep(1.millis) *> IO {
         released += 1
         ()
       }
diff --git a/common/shared/src/main/scala/munit/CatsEffectFixtures.scala b/common/shared/src/main/scala/munit/CatsEffectFixtures.scala
new file mode 100644
index 0000000..e81a9e2
--- /dev/null
+++ b/common/shared/src/main/scala/munit/CatsEffectFixtures.scala
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.{IO, Resource}
+
+trait CatsEffectFixtures extends CatsEffectFixturesPlatform { self: CatsEffectSuite =>
+
+  import CatsEffectSuite.Deferred
+
+  /** Similar to `ResourceSuiteLocalFixture`, but supported on both JVM and JS via several caveats.
+    * Instead of directly providing `T` provides a (memoized) `IO[T]` that is backed by a
+    * `Deferred[T]`. It is unsafe because on JS the resource is closed concurrently without
+    * backpressure,
+    * i.e. the suite will complete even while the resource has not closed yet. On JVM it is
+    * semantically equivalent to `ResourceSuiteLocalFixture`. Note also that constructing this
+    * fixture is impure because it unsafely allocates a `Deferred`.
+    */
+  object UnsafeResourceSuiteLocalDeferredFixture {
+
+    def apply[T](name: String, resource: Resource[IO, T]): Fixture[IO[T]] =
+      new Fixture[IO[T]](name) {
+        val value: Deferred[IO, (T, IO[Unit])] = Deferred.unsafe
+
+        def apply(): IO[T] = value.get.map(_._1)
+
+        override def beforeAll(): Unit = {
+          val resourceEffect = resource.allocated.flatMap(value.complete)
+          unsafeRunSyncOrForget(resourceEffect)
+        }
+
+        override def afterAll(): Unit = {
+          unsafeRunSyncOrForget(value.get.flatMap(_._2))
+        }
+      }
+  }
+
+}
diff --git a/common/shared/src/test/scala/munit/CatsEffectFixturesSpec.scala b/common/shared/src/test/scala/munit/CatsEffectFixturesSpec.scala
new file mode 100644
index 0000000..a07e9c1
--- /dev/null
+++ b/common/shared/src/test/scala/munit/CatsEffectFixturesSpec.scala
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2021 Typelevel
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package munit
+
+import cats.effect.{IO, Resource}
+import scala.concurrent.duration._
+
+class CatsEffectFixturesSpec extends CatsEffectSuite with CatsEffectAssertions {
+
+  @volatile var acquired: Int = 0
+  @volatile var released: Int = 0
+
+  val fixture = UnsafeResourceSuiteLocalDeferredFixture(
+    "fixture",
+    Resource.make(
+      IO.sleep(1.millis) *> IO {
+        acquired += 1
+        ()
+      }
+    )(_ =>
+      IO.sleep(1.millis) *> IO {
+        released += 1
+        ()
+      }
+    )
+  )
+
+  override def munitFixtures = List(fixture)
+
+  override def beforeAll(): Unit = {
+    assertEquals(acquired, 0)
+    assertEquals(released, 0)
+  }
+
+  override def afterAll(): Unit = {
+    assertEquals(acquired, 1)
+    // assertEquals(released, 1) // Release is async, no way to check
+  }
+
+  test("first test") {
+    fixture().assertEquals(())
+  }
+
+  test("second test") {
+    fixture().assertEquals(())
+  }
+
+}