diff --git a/.circleci/config.yml b/.circleci/config.yml
index 803997f..f296eb2 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1,6 +1,6 @@
 version: 2.1
 orbs:
-  ruby: circleci/ruby@1.1.2
+  ruby: circleci/ruby@1.2.0
 references:
   unit: &unit
     run:
@@ -45,6 +45,17 @@ jobs:
       - ruby/install-deps
       - <<: *unit
 
+  "ruby-3-1":
+    docker:
+      - image: 'cimg/base:stable'
+    steps:
+      - checkout
+      - ruby/install:
+          version: '3.1.0-preview1'
+      - run: ruby -v
+      - ruby/install-deps
+      - <<: *unit
+
   "lint":
     docker:
       - image: circleci/ruby:3.0
@@ -61,4 +72,5 @@ workflows:
       - "ruby-2-6"
       - "ruby-2-7"
       - "ruby-3-0"
+      - "ruby-3-1"
       - "lint"
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ac88977..64b3821 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## HEAD (unreleased)
 
+- Add support for Ruby 3.1 by updating `require_relative` logic (https://github.com/zombocom/dead_end/pull/120)
 - Requiring `dead_end/auto` is now deprecated please require `dead_end` instead (https://github.com/zombocom/dead_end/pull/119)
 - Requiring `dead_end/api` now loads code without monkeypatching core extensions (https://github.com/zombocom/dead_end/pull/119)
 - The interface `DeadEnd.handle_error` is declared public and stable (https://github.com/zombocom/dead_end/pull/119)
diff --git a/lib/dead_end/core_ext.rb b/lib/dead_end/core_ext.rb
index c89abd5..2886785 100644
--- a/lib/dead_end/core_ext.rb
+++ b/lib/dead_end/core_ext.rb
@@ -25,7 +25,9 @@ def require_relative(file)
     if Pathname.new(file).absolute?
       dead_end_original_require file
     else
-      dead_end_original_require File.expand_path("../#{file}", Kernel.caller_locations(1, 1)[0].absolute_path)
+      relative_from = caller_locations(1..1).first
+      relative_from_path = relative_from.absolute_path || relative_from.path
+      dead_end_original_require File.expand_path("../#{file}", relative_from_path)
     end
   rescue SyntaxError => e
     DeadEnd.handle_error(e)
diff --git a/spec/integration/ruby_command_line_spec.rb b/spec/integration/ruby_command_line_spec.rb
index df82dca..e124287 100644
--- a/spec/integration/ruby_command_line_spec.rb
+++ b/spec/integration/ruby_command_line_spec.rb
@@ -24,15 +24,22 @@ module DeadEnd
         Process.wait(d_pid)
         Process.wait(r_pid)
 
-        dead_end_methods_array = dead_end_methods_file.read.strip.lines.map(&:strip)
         kernel_methods_array = kernel_methods_file.read.strip.lines.map(&:strip)
+        dead_end_methods_array = dead_end_methods_file.read.strip.lines.map(&:strip)
         api_only_methods_array = api_only_methods_file.read.strip.lines.map(&:strip)
 
+        # In ruby 3.1.0-preview1 the `timeout` file is already required
+        # we can remove it if it exists to normalize the output for
+        # all ruby versions
+        [dead_end_methods_array, kernel_methods_array, api_only_methods_array].each do |array|
+          array.delete("timeout")
+        end
+
         methods = (dead_end_methods_array - kernel_methods_array).sort
-        expect(methods).to eq(["dead_end_original_load", "dead_end_original_require", "dead_end_original_require_relative", "timeout"])
+        expect(methods).to eq(["dead_end_original_load", "dead_end_original_require", "dead_end_original_require_relative"])
 
         methods = (api_only_methods_array - kernel_methods_array).sort
-        expect(methods).to eq(["timeout"])
+        expect(methods).to eq([])
       end
     end