diff --git a/README.md b/README.md
index e9637c9..8a070e9 100644
--- a/README.md
+++ b/README.md
@@ -2,21 +2,15 @@
 
 Simple Fluentd Plugin to count number of messages and outputs to log
 
-## Output Plugin Configuration
+## Requirements
 
-    <match foo.bar.**>
-      type flowcounter_simple
-      unit second
-    </match>
-
-This plugin does not emit, just writes counts into the log file as
-
-    plugin:out_flowcounter_simple  count:30  indicator:num  unit:second
+| fluent-plugin-flowcounter-simple  | fluentd | ruby |
+|-------------------|---------|------|
+| >= 0.1.0 | >= v1.0 | >= 2.4 |
+|  < 0.0.4 | >= v0.12.0 | >= 2.1 |
 
 ## Filter Plugin Configuration
 
-Fluentd >= v0.12
-
 ```apache
 <filter foo.bar.**>
   type flowcounter_simple
@@ -28,6 +22,17 @@ This filter plugin pass through records, and writes counts into the log file as
 
     plugin:out_flowcounter_simple  count:30  indicator:num  unit:second
 
+## Output Plugin Configuration
+
+    <match foo.bar.**>
+      type flowcounter_simple
+      unit second
+    </match>
+
+This plugin does not emit, just writes counts into the log file as
+
+    plugin:out_flowcounter_simple  count:30  indicator:num  unit:second
+
 ## Parameters
 
 - unit
diff --git a/fluent-plugin-flowcounter-simple.gemspec b/fluent-plugin-flowcounter-simple.gemspec
index b096460..963bf9d 100644
--- a/fluent-plugin-flowcounter-simple.gemspec
+++ b/fluent-plugin-flowcounter-simple.gemspec
@@ -14,7 +14,7 @@ Gem::Specification.new do |gem|
   gem.test_files    = gem.files.grep(%r{^(test|spec|features)/})
   gem.require_paths = ["lib"]
 
-  gem.add_runtime_dependency "fluentd"
+  gem.add_runtime_dependency "fluentd", [">= 1.0"]
   gem.add_development_dependency "rake"
   gem.add_development_dependency "pry"
   gem.add_development_dependency "pry-nav"