diff --git a/Gemfile b/Gemfile
index 8d9cf9d..fc7dae5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
 source 'https://rubygems.org'
 
-gem 'asciidoctor-revealjs' # latest released version
+gem 'asciidoctor-revealjs', "5.0.0.rc1" # latest released version
 gem 'asciidoctor-diagram'
diff --git a/Gemfile.lock b/Gemfile.lock
index 93bcc16..d445e9b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,20 +9,16 @@ GEM
       rexml
     asciidoctor-diagram-ditaamini (1.0.1)
     asciidoctor-diagram-plantuml (1.2021.8)
-    asciidoctor-revealjs (4.1.0)
+    asciidoctor-revealjs (5.0.0.rc1)
       asciidoctor (>= 2.0.0, < 3.0.0)
-      concurrent-ruby (~> 1.0)
-      thread_safe (~> 0.3.5)
-    concurrent-ruby (1.1.9)
     rexml (3.2.5)
-    thread_safe (0.3.6)
 
 PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
   asciidoctor-diagram
-  asciidoctor-revealjs
+  asciidoctor-revealjs (= 5.0.0.rc1)
 
 BUNDLED WITH
    2.2.24
diff --git a/default.nix b/default.nix
index 1682da4..8732f72 100644
--- a/default.nix
+++ b/default.nix
@@ -10,8 +10,8 @@ let
   revealjs = fetchFromGitHub {
     owner = "hakimel";
     repo = "reveal.js";
-    rev = "3.9.2";
-    sha256 = "1xaqgrib3m8ijnphph3aiz6d98w2mm1hlz643dargd12h4kx1lll";
+    rev = "4.1.2";
+    sha256 = "0z42q4wv6ji1vrkbdx52g2jj5qnxv155il2wly70q0vjphdk0kgh";
   };
 
 in derivation {
diff --git a/gemset.nix b/gemset.nix
index 69d794e..70527c4 100644
--- a/gemset.nix
+++ b/gemset.nix
@@ -41,25 +41,15 @@
     version = "1.2021.8";
   };
   asciidoctor-revealjs = {
-    dependencies = ["asciidoctor" "concurrent-ruby" "thread_safe"];
+    dependencies = ["asciidoctor"];
     groups = ["default"];
     platforms = [];
     source = {
       remotes = ["https://rubygems.org"];
-      sha256 = "03vmbcc3x059h17ry4qwk1p0yar9wgh87l2qssi307gy45cjw2mq";
+      sha256 = "1j7a0yadv458bnkfwczmjzkvirwlahpay3j2slsxd7j2jj93lbn0";
       type = "gem";
     };
-    version = "4.1.0";
-  };
-  concurrent-ruby = {
-    groups = ["default"];
-    platforms = [];
-    source = {
-      remotes = ["https://rubygems.org"];
-      sha256 = "0nwad3211p7yv9sda31jmbyw6sdafzmdi2i2niaz6f0wk5nq9h0f";
-      type = "gem";
-    };
-    version = "1.1.9";
+    version = "5.0.0.rc1";
   };
   rexml = {
     groups = ["default"];
@@ -71,14 +61,4 @@
     };
     version = "3.2.5";
   };
-  thread_safe = {
-    groups = ["default"];
-    platforms = [];
-    source = {
-      remotes = ["https://rubygems.org"];
-      sha256 = "0nmhcgq6cgz44srylra07bmaw99f5271l0dpsvl5f75m44l0gmwy";
-      type = "gem";
-    };
-    version = "0.3.6";
-  };
 }