diff --git a/steps/discover-repos.rb b/steps/discover-repos.rb
index 20ab5146..44688421 100755
--- a/steps/discover-repos.rb
+++ b/steps/discover-repos.rb
@@ -121,7 +121,7 @@ def cooldown(opts, found)
       size: i[:size],
       open_issues_count: i[:open_issues_count],
       description: "\"#{i[:description]}\"",
-      topics: i[:topics].join('')
+      topics: i[:topics].join(' ')
     }
     puts "Found #{i[:full_name].inspect} GitHub repo ##{found.count} \
 (#{i[:forks_count]} forks, #{i[:stargazers_count]} stars) with license: #{i[:license][:key]}"