diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index f3d396a..5c14dba 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -14,7 +14,7 @@ env:
   #
   # If updating this value, you probably also want to add a new version to the
   # spec version matrix below.
-  RUBY_VERSION: "3.4"
+  RUBY_VERSION: "4.0"
 
   # A suitable URL for a test database.
   TEST_DATABASE_NAME: river_test
@@ -134,6 +134,7 @@ jobs:
           - "3.2"
           - "3.3"
           - "3.4"
+          - "4.0"
 
     services:
       postgres:
diff --git a/.tool-versions b/.tool-versions
index 380cf51..b77860b 100644
--- a/.tool-versions
+++ b/.tool-versions
@@ -1 +1 @@
-ruby 3.4
+ruby 4.0
diff --git a/Gemfile.lock b/Gemfile.lock
index 5d1e590..23ce27e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -13,64 +13,67 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (8.0.4.1)
+    activesupport (8.1.3)
       base64
-      benchmark (>= 0.3)
       bigdecimal
       concurrent-ruby (~> 1.0, >= 1.3.1)
       connection_pool (>= 2.2.5)
       drb
       i18n (>= 1.6, < 2)
+      json
       logger (>= 1.4.2)
-      minitest (>= 5.1, < 6)
+      minitest (>= 5.1)
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
     ast (2.4.3)
     base64 (0.3.0)
-    benchmark (0.5.0)
-    bigdecimal (4.0.1)
+    bigdecimal (4.1.0)
     concurrent-ruby (1.3.6)
     connection_pool (3.0.2)
     csv (3.3.5)
-    date (3.4.1)
-    debug (1.11.0)
+    date (3.5.1)
+    debug (1.11.1)
       irb (~> 1.10)
       reline (>= 0.3.8)
     diff-lcs (1.6.2)
     docile (1.4.1)
     drb (2.2.3)
-    erb (5.1.1)
-    ffi (1.17.2-arm64-darwin)
-    ffi (1.17.2-x86_64-linux-gnu)
-    fileutils (1.7.3)
+    erb (6.0.2)
+    ffi (1.17.4-arm64-darwin)
+    ffi (1.17.4-x86_64-linux-gnu)
+    fileutils (1.8.0)
     i18n (1.14.8)
       concurrent-ruby (~> 1.0)
-    io-console (0.8.1)
-    irb (1.15.2)
+    io-console (0.8.2)
+    irb (1.17.0)
       pp (>= 0.6.0)
+      prism (>= 1.3.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
-    json (2.15.2.1)
+    json (2.19.3)
     language_server-protocol (3.17.0.5)
     lint_roller (1.1.0)
-    listen (3.9.0)
+    listen (3.10.0)
+      logger
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.7.0)
-    minitest (5.27.0)
+    minitest (6.0.2)
+      drb (~> 2.0)
+      prism (~> 1.5)
     mutex_m (0.3.0)
     parallel (1.27.0)
-    parser (3.3.9.0)
+    parser (3.3.11.1)
       ast (~> 2.4.1)
       racc
-    pg (1.6.2-arm64-darwin)
-    pg (1.6.2-x86_64-linux)
+    pg (1.6.3-arm64-darwin)
+    pg (1.6.3-x86_64-linux)
     pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
-    prism (1.6.0)
-    psych (5.2.6)
+    prism (1.9.0)
+    psych (5.3.1)
       date
       stringio
     racc (1.8.1)
@@ -78,22 +81,23 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rbs (3.9.5)
+    rbs (3.10.4)
       logger
-    rdoc (6.15.0)
+      tsort
+    rdoc (7.2.0)
       erb
       psych (>= 4.0.0)
       tsort
     regexp_parser (2.11.3)
-    reline (0.6.2)
+    reline (0.6.3)
       io-console (~> 0.5)
     rspec-core (3.13.6)
       rspec-support (~> 3.13.0)
     rspec-expectations (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.6)
-    rubocop (1.80.2)
+    rspec-support (3.13.7)
+    rubocop (1.84.2)
       json (~> 2.3)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.1.0)
@@ -101,19 +105,19 @@ GEM
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 2.9.3, < 3.0)
-      rubocop-ast (>= 1.46.0, < 2.0)
+      rubocop-ast (>= 1.49.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 4.0)
-    rubocop-ast (1.47.1)
+    rubocop-ast (1.49.1)
       parser (>= 3.3.7.2)
-      prism (~> 1.4)
-    rubocop-performance (1.25.0)
+      prism (~> 1.7)
+    rubocop-performance (1.26.1)
       lint_roller (~> 1.1)
       rubocop (>= 1.75.0, < 2.0)
-      rubocop-ast (>= 1.38.0, < 2.0)
+      rubocop-ast (>= 1.47.1, < 2.0)
     ruby-progressbar (1.13.0)
     securerandom (0.4.1)
-    sequel (5.97.0)
+    sequel (5.102.0)
       bigdecimal
     simplecov (0.22.0)
       docile (~> 1.1)
@@ -121,18 +125,18 @@ GEM
       simplecov_json_formatter (~> 0.1)
     simplecov-html (0.13.2)
     simplecov_json_formatter (0.1.4)
-    standard (1.51.1)
+    standard (1.54.0)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.0)
-      rubocop (~> 1.80.2)
+      rubocop (~> 1.84.0)
       standard-custom (~> 1.0.0)
       standard-performance (~> 1.8)
     standard-custom (1.0.2)
       lint_roller (~> 1.0)
       rubocop (~> 1.50)
-    standard-performance (1.8.0)
+    standard-performance (1.9.0)
       lint_roller (~> 1.1)
-      rubocop-performance (~> 1.25.0)
+      rubocop-performance (~> 1.26.0)
     steep (1.10.0)
       activesupport (>= 5.1)
       concurrent-ruby (>= 1.1.10)
@@ -150,8 +154,8 @@ GEM
       strscan (>= 1.0.0)
       terminal-table (>= 2, < 5)
       uri (>= 0.12.0)
-    stringio (3.1.7)
-    strscan (3.1.5)
+    stringio (3.2.0)
+    strscan (3.1.7)
     terminal-table (4.0.0)
       unicode-display_width (>= 1.1.1, < 4)
     tsort (0.2.0)
@@ -159,13 +163,11 @@ GEM
       concurrent-ruby (~> 1.0)
     unicode-display_width (3.2.0)
       unicode-emoji (~> 4.1)
-    unicode-emoji (4.1.0)
+    unicode-emoji (4.2.0)
     uri (1.1.1)
 
 PLATFORMS
-  arm64-darwin-22
-  arm64-darwin-23
-  arm64-darwin-24
+  arm64-darwin-25
   x86_64-linux
 
 DEPENDENCIES
diff --git a/driver/riverqueue-activerecord/Gemfile.lock b/driver/riverqueue-activerecord/Gemfile.lock
index 3897ee8..b5b56f1 100644
--- a/driver/riverqueue-activerecord/Gemfile.lock
+++ b/driver/riverqueue-activerecord/Gemfile.lock
@@ -14,13 +14,13 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    activemodel (8.1.2.1)
-      activesupport (= 8.1.2.1)
-    activerecord (8.1.2.1)
-      activemodel (= 8.1.2.1)
-      activesupport (= 8.1.2.1)
+    activemodel (8.1.3)
+      activesupport (= 8.1.3)
+    activerecord (8.1.3)
+      activemodel (= 8.1.3)
+      activesupport (= 8.1.3)
       timeout (>= 0.4.0)
-    activesupport (8.1.2.1)
+    activesupport (8.1.3)
       base64
       bigdecimal
       concurrent-ruby (~> 1.0, >= 1.3.1)
@@ -33,101 +33,115 @@ GEM
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
-    ast (2.4.2)
+    ast (2.4.3)
     base64 (0.3.0)
-    bigdecimal (4.0.1)
+    bigdecimal (4.1.0)
     concurrent-ruby (1.3.6)
     connection_pool (3.0.2)
-    date (3.4.1)
-    debug (1.10.0)
+    date (3.5.1)
+    debug (1.11.1)
       irb (~> 1.10)
       reline (>= 0.3.8)
-    diff-lcs (1.5.1)
+    diff-lcs (1.6.2)
     docile (1.4.1)
     drb (2.2.3)
+    erb (6.0.2)
     i18n (1.14.8)
       concurrent-ruby (~> 1.0)
-    io-console (0.8.0)
-    irb (1.14.3)
+    io-console (0.8.2)
+    irb (1.17.0)
+      pp (>= 0.6.0)
+      prism (>= 1.3.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
-    json (2.19.2)
-    language_server-protocol (3.17.0.3)
+    json (2.19.3)
+    language_server-protocol (3.17.0.5)
     lint_roller (1.1.0)
     logger (1.7.0)
     minitest (6.0.2)
       drb (~> 2.0)
       prism (~> 1.5)
-    parallel (1.26.3)
-    parser (3.3.6.0)
+    parallel (1.27.0)
+    parser (3.3.11.1)
       ast (~> 2.4.1)
       racc
-    pg (1.5.9)
+    pg (1.6.3-arm64-darwin)
+    pg (1.6.3-x86_64-linux)
+    pp (0.6.3)
+      prettyprint
+    prettyprint (0.2.0)
     prism (1.9.0)
-    psych (5.2.2)
+    psych (5.3.1)
       date
       stringio
     racc (1.8.1)
     rainbow (3.1.1)
-    rdoc (6.10.0)
+    rdoc (7.2.0)
+      erb
       psych (>= 4.0.0)
-    regexp_parser (2.10.0)
-    reline (0.6.0)
+      tsort
+    regexp_parser (2.11.3)
+    reline (0.6.3)
       io-console (~> 0.5)
-    rspec-core (3.13.2)
+    rspec-core (3.13.6)
       rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.3)
+    rspec-expectations (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.2)
-    rubocop (1.69.2)
+    rspec-support (3.13.7)
+    rubocop (1.84.2)
       json (~> 2.3)
-      language_server-protocol (>= 3.17.0)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.1.0)
       parallel (~> 1.10)
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 2.9.3, < 3.0)
-      rubocop-ast (>= 1.36.2, < 2.0)
+      rubocop-ast (>= 1.49.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 4.0)
-    rubocop-ast (1.37.0)
-      parser (>= 3.3.1.0)
-    rubocop-performance (1.23.0)
-      rubocop (>= 1.48.1, < 2.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-ast (1.49.1)
+      parser (>= 3.3.7.2)
+      prism (~> 1.7)
+    rubocop-performance (1.26.1)
+      lint_roller (~> 1.1)
+      rubocop (>= 1.75.0, < 2.0)
+      rubocop-ast (>= 1.47.1, < 2.0)
     ruby-progressbar (1.13.0)
     securerandom (0.4.1)
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.13.1)
+    simplecov-html (0.13.2)
     simplecov_json_formatter (0.1.4)
-    standard (1.43.0)
+    standard (1.54.0)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.0)
-      rubocop (~> 1.69.1)
+      rubocop (~> 1.84.0)
       standard-custom (~> 1.0.0)
-      standard-performance (~> 1.6)
+      standard-performance (~> 1.8)
     standard-custom (1.0.2)
       lint_roller (~> 1.0)
       rubocop (~> 1.50)
-    standard-performance (1.6.0)
+    standard-performance (1.9.0)
       lint_roller (~> 1.1)
-      rubocop-performance (~> 1.23.0)
-    stringio (3.1.2)
-    timeout (0.6.0)
+      rubocop-performance (~> 1.26.0)
+    stringio (3.2.0)
+    timeout (0.6.1)
+    tsort (0.2.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    unicode-display_width (3.1.2)
-      unicode-emoji (~> 4.0, >= 4.0.4)
-    unicode-emoji (4.0.4)
+    unicode-display_width (3.2.0)
+      unicode-emoji (~> 4.1)
+    unicode-emoji (4.2.0)
     uri (1.1.1)
 
 PLATFORMS
   arm64-darwin-22
   arm64-darwin-23
   arm64-darwin-24
+  arm64-darwin-25
   x86_64-linux
 
 DEPENDENCIES
diff --git a/driver/riverqueue-sequel/Gemfile.lock b/driver/riverqueue-sequel/Gemfile.lock
index e3e30ff..08a59f3 100644
--- a/driver/riverqueue-sequel/Gemfile.lock
+++ b/driver/riverqueue-sequel/Gemfile.lock
@@ -13,71 +13,77 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    ast (2.4.2)
-    bigdecimal (3.1.9)
-    diff-lcs (1.5.1)
+    ast (2.4.3)
+    bigdecimal (4.1.0)
+    diff-lcs (1.6.2)
     docile (1.4.1)
-    json (2.9.1)
-    language_server-protocol (3.17.0.3)
+    json (2.19.3)
+    language_server-protocol (3.17.0.5)
     lint_roller (1.1.0)
-    parallel (1.26.3)
-    parser (3.3.6.0)
+    parallel (1.27.0)
+    parser (3.3.11.1)
       ast (~> 2.4.1)
       racc
-    pg (1.5.9)
+    pg (1.6.3-arm64-darwin)
+    pg (1.6.3-x86_64-linux)
+    prism (1.9.0)
     racc (1.8.1)
     rainbow (3.1.1)
-    regexp_parser (2.10.0)
-    rspec-core (3.13.2)
+    regexp_parser (2.11.3)
+    rspec-core (3.13.6)
       rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.3)
+    rspec-expectations (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.2)
-    rubocop (1.69.2)
+    rspec-support (3.13.7)
+    rubocop (1.84.2)
       json (~> 2.3)
-      language_server-protocol (>= 3.17.0)
+      language_server-protocol (~> 3.17.0.2)
+      lint_roller (~> 1.1.0)
       parallel (~> 1.10)
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 2.9.3, < 3.0)
-      rubocop-ast (>= 1.36.2, < 2.0)
+      rubocop-ast (>= 1.49.0, < 2.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 2.4.0, < 4.0)
-    rubocop-ast (1.37.0)
-      parser (>= 3.3.1.0)
-    rubocop-performance (1.23.0)
-      rubocop (>= 1.48.1, < 2.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-ast (1.49.1)
+      parser (>= 3.3.7.2)
+      prism (~> 1.7)
+    rubocop-performance (1.26.1)
+      lint_roller (~> 1.1)
+      rubocop (>= 1.75.0, < 2.0)
+      rubocop-ast (>= 1.47.1, < 2.0)
     ruby-progressbar (1.13.0)
-    sequel (5.87.0)
+    sequel (5.102.0)
       bigdecimal
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.13.1)
+    simplecov-html (0.13.2)
     simplecov_json_formatter (0.1.4)
-    standard (1.43.0)
+    standard (1.54.0)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.0)
-      rubocop (~> 1.69.1)
+      rubocop (~> 1.84.0)
       standard-custom (~> 1.0.0)
-      standard-performance (~> 1.6)
+      standard-performance (~> 1.8)
     standard-custom (1.0.2)
       lint_roller (~> 1.0)
       rubocop (~> 1.50)
-    standard-performance (1.6.0)
+    standard-performance (1.9.0)
       lint_roller (~> 1.1)
-      rubocop-performance (~> 1.23.0)
-    unicode-display_width (3.1.2)
-      unicode-emoji (~> 4.0, >= 4.0.4)
-    unicode-emoji (4.0.4)
+      rubocop-performance (~> 1.26.0)
+    unicode-display_width (3.2.0)
+      unicode-emoji (~> 4.1)
+    unicode-emoji (4.2.0)
 
 PLATFORMS
   arm64-darwin-22
   arm64-darwin-23
   arm64-darwin-24
+  arm64-darwin-25
   x86_64-linux
 
 DEPENDENCIES
diff --git a/lib/client.rb b/lib/client.rb
index b5a8949..88de340 100644
--- a/lib/client.rb
+++ b/lib/client.rb
@@ -129,7 +129,7 @@ def insert_many(args)
 
       @driver.job_insert_many(all_params)
         .map do |job, unique_skipped_as_duplicate|
-        InsertResult.new(job, unique_skipped_as_duplicated: unique_skipped_as_duplicate)
+          InsertResult.new(job, unique_skipped_as_duplicated: unique_skipped_as_duplicate)
       end
     end