diff --git a/Gemfile.lock b/Gemfile.lock
index 1fcbb37..0155660 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,7 +2,7 @@ PATH
   remote: .
   specs:
     smart_todo (1.7.0)
-      prism
+      prism (~> 0.15)
 
 GEM
   remote: https://rubygems.org/
diff --git a/lib/smart_todo/comment_parser.rb b/lib/smart_todo/comment_parser.rb
index 4a804a1..2c44232 100644
--- a/lib/smart_todo/comment_parser.rb
+++ b/lib/smart_todo/comment_parser.rb
@@ -8,12 +8,22 @@ def initialize
       @todos = []
     end
 
-    def parse(source, filepath = "-e")
-      parse_comments(Prism.parse_comments(source), filepath)
-    end
+    if Prism.respond_to?(:parse_comments)
+      def parse(source, filepath = "-e")
+        parse_comments(Prism.parse_comments(source), filepath)
+      end
+
+      def parse_file(filepath)
+        parse_comments(Prism.parse_file_comments(filepath), filepath)
+      end
+    else
+      def parse(source, filepath = "-e")
+        parse_comments(Prism.parse(source, filepath).comments, filepath)
+      end
 
-    def parse_file(filepath)
-      parse_comments(Prism.parse_file_comments(filepath), filepath)
+      def parse_file(filepath)
+        parse_comments(Prism.parse_file(filepath).comments, filepath)
+      end
     end
 
     class << self
@@ -26,11 +36,21 @@ def parse(source)
 
     private
 
+    if defined?(Prism::InlineComment)
+      def inline?(comment)
+        comment.is_a?(Prism::InlineComment)
+      end
+    else
+      def inline?(comment)
+        comment.type == :inline
+      end
+    end
+
     def parse_comments(comments, filepath)
       current_todo = nil
 
       comments.each do |comment|
-        next unless comment.is_a?(Prism::InlineComment)
+        next unless inline?(comment)
 
         source = comment.location.slice
 
diff --git a/smart_todo.gemspec b/smart_todo.gemspec
index 5ebc21c..77814d3 100644
--- a/smart_todo.gemspec
+++ b/smart_todo.gemspec
@@ -33,7 +33,7 @@ Gem::Specification.new do |spec|
   spec.executables   = ["smart_todo"]
   spec.require_paths = ["lib"]
 
-  spec.add_runtime_dependency("prism")
+  spec.add_runtime_dependency("prism", "~> 0.15")
   spec.add_development_dependency("bundler", ">= 1.17")
   spec.add_development_dependency("minitest", "~> 5.0")
   spec.add_development_dependency("rake", ">= 10.0")