Add poolboy and retry effects

Author: Kleidukos

content/ecosystem/concurrency.md

@@ -17,3 +17,19 @@ title = "Concurrency"
     </dt>
     <dd> Structured concurrency for the effectful ecosystem.</dd>
 </dl>
+
+<dl>
+    <dt>
+        <a href="https://github.com/blackheaven/poolboy-effectful#readme"><code>blackheaven/poolboy-effectful</code></a>
+        <img src="https://img.shields.io/hackage/v/poolboy-effectful.svg" alt="Hackage" data-canonical-src="https://img.shields.io/hackage/v/poolboy-effectful.svg" style="max-width: 100%;">
+    </dt>
+    <dd> Simple work queue for bounded concurrency (effectful wrapper).</dd>
+</dl>
+
+<dl>
+    <dt>
+        <a href="https://github.com/change-metrics/retry-effectful#readme"><code>change-metrics/retry-effectful</code></a>
+        <img src="https://img.shields.io/hackage/v/retry-effectful.svg" alt="Hackage" data-canonical-src="https://img.shields.io/hackage/v/retry-effectful.svg" style="max-width: 100%;">
+    </dt>
+    <dd> Adaptation of the retry library for the effectful ecosystem..</dd>
+</dl>