diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Revision history for digraph
 
+## 0.2.1 -- 2021-06-24
+
+* Build with GHC-9
+
 ## 0.2 -- 2020-05-19
 
 * Fix the `twentyChainGraph` to have diameter 3 and match the respective graph
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,5 +1,3 @@
-[![Build Status](https://travis-ci.org/kadena-io/digraph.svg?branch=master)](https://travis-ci.org/kadena-io/digraph)
-
 Directed graphs in adjacency set representation. The implementation is based
 on `Data.HashMap.Strict` and `Data.HashSet` from the [unordered-containers
 package](https://hackage.haskell.org/package/unordered-containers).
diff --git a/digraph.cabal b/digraph.cabal
--- a/digraph.cabal
+++ b/digraph.cabal
@@ -1,6 +1,6 @@
-cabal-version: 2.2
+cabal-version: 2.4
 name: digraph
-version: 0.2
+version: 0.2.1
 synopsis: Directed Graphs
 description: Directed graphs implementation that is based on unordered-containers
 homepage: https://github.com/kadena-io/digraph
@@ -9,12 +9,12 @@
 license-file: LICENSE
 author: Lars Kuhtz
 maintainer: lars@kadena.io
-copyright: Copyright (c) 2019 - 2020, Kadena LLC
+copyright: Copyright (c) 2019 - 2021, Kadena LLC
 category: Data, Mathematics
 tested-with:
-      GHC==8.10.1
-    , GHC==8.8.3
-    , GHC==8.6.5
+    GHC==9.0.1
+    GHC==8.10.5
+    GHC==8.8.4
 extra-source-files:
     README.md
     CHANGELOG.md
@@ -29,11 +29,11 @@
     ghc-options:
         -Wall
     exposed-modules:
-          Data.DiGraph
-        , Data.DiGraph.FloydWarshall
-        , Data.DiGraph.Random
+        Data.DiGraph
+        Data.DiGraph.FloydWarshall
+        Data.DiGraph.Random
     build-depends:
-          base >=4.10 && <4.15
+        , base >=4.10 && <4.16
         , containers >=0.5
         , deepseq >=1.4
         , hashable >=1.2
@@ -53,15 +53,15 @@
         -threaded
         -with-rtsopts=-N
     other-modules:
-          Data.DiGraph.Test
-        , Data.DiGraph.Random.Test
+        Data.DiGraph.Test
+        Data.DiGraph.Random.Test
     build-depends:
         -- internal
-          digraph
+        , digraph
 
         -- external
         , QuickCheck >=2.11
-        , base >=4.10 && <4.15
+        , base >=4.10 && <4.16
         , fgl >=5.7
         , hashable >=1.2
         , massiv >=0.3
diff --git a/src/Data/DiGraph/Random.hs b/src/Data/DiGraph/Random.hs
--- a/src/Data/DiGraph/Random.hs
+++ b/src/Data/DiGraph/Random.hs
@@ -64,7 +64,9 @@
     :: Natural
     -> Natural
     -> IO (Maybe (DiGraph Int))
-rrgIO n d = MWC.withSystemRandom $ \gen -> rrg @IO (`MWC.uniformR` gen) n d
+rrgIO n d = do
+    gen <- MWC.createSystemRandom
+    rrg @IO (`MWC.uniformR` gen) n d
 
 -- | Undirected, irreflexive random regular graph.
 --