diff --git a/Gemfile b/Gemfile
index 8f5dbf2..65cba2e 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,4 +5,5 @@ gem "octokit"
 group :development do
   gem "pry-byebug"
   gem "rspec"
+  gem "hashie"
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index fdfb294..3de6f47 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -8,6 +8,7 @@ GEM
     diff-lcs (1.4.4)
     faraday (1.0.1)
       multipart-post (>= 1.2, < 3)
+    hashie (5.0.0)
     method_source (1.0.0)
     multipart-post (2.1.1)
     octokit (4.18.0)
@@ -41,6 +42,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  hashie
   octokit
   pry-byebug
   rspec
diff --git a/actions/bubble_merge/git_client.rb b/actions/bubble_merge/git_client.rb
index cd7ff0f..d66c940 100644
--- a/actions/bubble_merge/git_client.rb
+++ b/actions/bubble_merge/git_client.rb
@@ -3,7 +3,7 @@
 
 module Squiddy
   class GitClient
-    attr_reader :client, :event, :pr, :repo
+    attr_reader :client, :event, :pr
 
     CHECK_STATUSES = %w[queued in_progress completed].freeze
     CHECK_CONCLUSIONS = %w[success failure neutral cancelled skipped timed_out action_required stale].freeze
@@ -16,25 +16,56 @@ def initialize
       @client = Octokit::Client.new(access_token: ENV["GITHUB_TOKEN"])
       @event = git_event
       @pr = pull_request
-      @repo = repository
     end
 
     def bubble_merge
       if already_merged?
         client.add_comment(repo_name, pr_number, 'This PR is already merged.')
       else
-        merge_and_close_pr
+        wait_for_pr_to_match_branch do |merge_sha|
+          merge_and_close_pr(merge_sha)
+        end
       end
     end
 
     private
 
+    def wait_for_pr_to_match_branch
+      retry_sleeps = [1, 2, 3, 5, 8]
+
+      loop do
+        expected = branch_head_sha
+        actual = pull_request_head_sha
+
+        if actual == expected
+          puts "PR HEAD #{actual[0..10]} matches #{branch} HEAD #{expected[0..10]}; merging..."
+          yield expected
+          return
+        elsif s = retry_sleeps.shift
+          puts "PR HEAD #{actual[0..10]} did not match #{branch} HEAD #{expected[0..10]}; waiting for #{s}s..."
+          sleep s
+          next
+        else
+          raise "PR HEAD #{actual[0..10]} did not match #{branch} HEAD #{expected[0..10]}; exiting"
+        end
+      end
+    end
+
     def already_merged?
       client.pull_merged?(repo_name, pr_number)
     end
 
-    def merge_and_close_pr
-      merge
+    def merge_and_close_pr(merge_sha)
+      puts "PR ##{pr_number}: merging #{branch}@#{merge_sha} into #{base_branch}"
+      client.merge_pull_request(
+        repo_name,
+        pr_number,
+        commit_message,
+        {
+          merge_method: 'merge',
+          sha: merge_sha
+        }
+      )
       delete_branch
     rescue StandardError => e
       message = <<~MESSAGE
@@ -46,59 +77,31 @@ def merge_and_close_pr
       client.add_comment(repo_name, pr_number, message)
     end
 
-    def merge
-      client.merge(
-        repo_name,
-        base_branch,
-        branch,
-        {
-          merge_method: 'rebase',
-          commit_message: commit_message,
-          sha: main_sha
-        }
-      )
-    end
-
     def delete_branch
-      return if repo.delete_branch_on_merge
+      return if repository.delete_branch_on_merge
 
+      puts "PR ##{pr_number}: deleting #{branch}"
       client.delete_branch(repo_name, branch)
     end
 
-    def main_sha
-      client.list_commits(repo_name).last.sha
-    end
-
     def branch
-      pr[:head][:ref]
+      pr.head.ref
     end
 
     def base_branch
-      pr[:base][:ref]
+      pr.base.ref
     end
 
     def pr_number
       event.dig('issue', 'number')
     end
 
-    def pr_status
-      checks = head_commit_checks[:check_suites]
-
-      if checks.any? { |check| check[:status] != 'completed' }
-        'pending'
-      elsif checks.any? { |check| check[:conclusion] != 'success' }
-        'failure'
-      else
-        'success'
-      end
-    end
-
-    def head_commit_checks
-      client.check_suites_for_ref(repo_name, head_commit_sha)
+    def branch_head_sha
+      client.branch(repo_name, branch).commit.sha
     end
 
-    def head_commit_sha
-      client.pull_request_commits(repo_name, pr_number).last.sha
+    def pull_request_head_sha
+      client.pull_request(repo_name, pr_number).head.sha
     end
 
     def comment_author
diff --git a/lib/squiddy.rb b/lib/squiddy.rb
deleted file mode 100644
index 6c7b62a..0000000
--- a/lib/squiddy.rb
+++ /dev/null
@@ -1,91 +0,0 @@
-require 'trello'
-
-require_relative 'squiddy/event'
-require_relative 'squiddy/pull_request'
-require_relative 'squiddy/trello'
-
-module Squiddy
-  # TrelloPullRequest automatically creates a checklist on a Trello card called
-  # "Pull Requests", and adds the pull request URL as an item.
-  #
-  # If the Pull Request is in a closed state, then it marks the item as
-  # complete
-  class TrelloPullRequest
-    def self.run(pull_request_number:)
-      fail "pull_request_number is nil" if pull_request_number.nil?
-
-      event = Squiddy::Event.new
-
-      return nil unless event.type == "pull_request"
-      pull_request = Squiddy::PullRequest.new(event.repository, pull_request_number)
-
-      trello_regex = /https:\/\/trello\.com\/c\/\w+/
-
-      trello_card = pull_request.body_regex(trello_regex)
-      return nil unless trello_card
-
-      begin
-        trello = Squiddy::Trello::Checklist.new(trello_card)
-
-        item = pull_request.url
-
-        if pull_request.open?
-          puts "#{item} has been opened or edited"
-
-          unless trello.checklist_exist?
-            trello.create_checklist
-            puts "Checklist created"
-          end
-
-          unless trello.item_exist?(item)
-            trello.add_item(item)
-            puts "Added #{item} to checklist"
-          end
-        end
-
-        if pull_request.closed?
-          puts "#{item} has been merged or closed"
-
-          if trello.item_exist?(item)
-            trello.mark_item_as_complete(item)
-            puts "#{item} marked as complete"
-          end
-        end
-      rescue Squiddy::Trello::Checklist::ChecklistNotFound => e
-        e.message
-      end
-    end
-  end
-
-  # TrelloDependabot will create a card on a specific board and list for every
-  # pull request which has a specific label that is configured in dependabot,
-  # with the body and link to the PR
-  class TrelloDependabot
-    def self.run(board_id:,list_create_id:,list_done_id:,github_label:,pull_request_number:)
-      fail "pull_request_number is nil" if pull_request_number.nil?
-
-      event = Squiddy::Event.new
-      return nil unless event.type == "pull_request"
-
-      pull_request = Squiddy::PullRequest.new(event.repository, pull_request_number)
-      return nil unless pull_request.labels.include?(github_label)
-
-      board = ::Trello::Board.find(board_id)
-      card = board.cards.find { |card| card.name == pull_request.title }
-
-      if pull_request.open?
-        return nil if card
-
-        dependabot_label = board.labels.find {|label| label.name == "Dependabot" } || ::Trello::Label.create(board_id: board_id, name: "Dependabot")
-
-        ::Trello::Card.create(list_id: list_create_id, name: pull_request.title, desc: pull_request.url, card_labels: [dependabot_label.id], pos: "bottom")
-      end
-
-      if pull_request.closed?
-        return nil unless card
-
-        card.move_to_list(list_done_id)
-      end
-    end
-  end
-end
diff --git a/spec/actions/bubble_merge/git_client_spec.rb b/spec/actions/bubble_merge/git_client_spec.rb
index bcbc89c..f31767c 100644
--- a/spec/actions/bubble_merge/git_client_spec.rb
+++ b/spec/actions/bubble_merge/git_client_spec.rb
@@ -1,5 +1,6 @@
 require 'spec_helper'
 
+require 'hashie/mash'
 require_relative '../../../actions/bubble_merge/git_client'
 
 RSpec.describe Squiddy::GitClient do
@@ -20,33 +21,47 @@
       }
     }.to_json
   }
-  let(:pr_data) { { base: { ref: 'test-base-branch' }, head: { ref: 'test-branch' } } }
-  let(:octokit_client) { instance_double('Octokit::Client', merge: nil, delete_branch: nil, add_comment: nil) }
-  let(:head_commit_status) do
-    {
-      total_count: '1',
-      check_suites: [
-        {
-          id: '1',
-          status: 'completed',
-          conclusion: 'success'
-        }
-      ]
-    }
-  end
+  let(:pull_request) {
+    Hashie::Mash.new({
+      base: { ref: 'test-base-branch' },
+      head: { ref: 'test-branch', sha: '1234' }
+    })
+  }
+  let(:branch) {
+    Hashie::Mash.new({
+      commit: { sha: '1234' },
+    })
+  }
+  let(:pull_merged?) { false }
+  let(:octokit_client) {
+    instance_double(
+      'Octokit::Client',
+      merge_pull_request: nil,
+      delete_branch: nil,
+      add_comment: nil,
+      pull_merged?: pull_merged?
+    )
+  }
   let(:repository) { double("Repository", delete_branch_on_merge: false) }
 
   before do
     stub_const('ENV', 'GITHUB_EVENT' => event, 'GITHUB_TOKEN' => 'token')
     allow(Octokit::Client).to receive(:new).and_return(octokit_client)
-    allow(octokit_client).to receive(:pull_request).with('test-user/test-repo', 'test-pr-number').and_return(pr_data)
-    allow(octokit_client).to receive_message_chain(:list_commits, :last, :sha).and_return('1234')
-    allow(octokit_client).to receive(:pull_merged?).and_return(false)
-    allow(octokit_client).to receive_message_chain(:pull_request_commits, :last, :sha).and_return('5678')
-    allow(octokit_client).to receive(:check_suites_for_ref).and_return(head_commit_status)
+    allow(octokit_client).to receive(:pull_request).with('test-user/test-repo', 'test-pr-number').and_return(pull_request)
+    allow(octokit_client).to receive(:branch).with('test-user/test-repo', 'test-branch').and_return(branch)
     allow(octokit_client).to receive(:repository).with('test-user/test-repo').and_return(repository)
   end
 
+  around do |example|
+    begin
+      old_stdout = $stdout
+      $stdout = StringIO.new(String.new, 'w')
+      example.call
+    ensure
+      $stdout = old_stdout
+    end
+  end
+
   context '#bubble_merge' do
     let(:commit_message) {
       <<~MESSAGE
@@ -64,13 +79,12 @@
     }
 
     it 'merges successfully' do
-      expect(octokit_client).to receive(:merge).with(
+      expect(octokit_client).to receive(:merge_pull_request).with(
         'test-user/test-repo',
-        'test-base-branch',
-        'test-branch',
+        'test-pr-number',
+        commit_message,
         {
-          commit_message: commit_message,
-          merge_method: 'rebase',
+          merge_method: 'merge',
           sha: '1234'
         }
       )
@@ -93,7 +107,7 @@
       }
 
       before do
-        allow(octokit_client).to receive(:merge).and_raise(Octokit::Conflict.new)
+        allow(octokit_client).to receive(:merge_pull_request).and_raise(Octokit::Conflict.new)
       end
 
       it 'prints an error message' do
@@ -113,7 +127,7 @@
       end
 
       it 'does not attempt to merge again' do
-        expect(octokit_client).not_to receive(:merge)
+        expect(octokit_client).not_to receive(:merge_pull_request)
         subject.bubble_merge
       end
 
@@ -123,6 +137,42 @@
       end
     end
 
+    context 'when the PR branch and PR are out of sync' do
+      let(:pull_request_head) { double(:pull_request_head, ref: 'test-branch') }
+      let(:pull_request) {
+        Hashie::Mash.new({
+          base: { ref: 'test-base-branch' },
+          head: pull_request_head,
+        })
+      }
+      let(:branch) {
+        Hashie::Mash.new({
+          commit: { sha: '1234' },
+        })
+      }
+
+      before do
+        allow(subject).to receive(:sleep)
+      end
+
+      it 'waits 5 times and then fails' do
+        allow(pull_request_head).to receive(:sha).and_return('5678')
+
+        expect {
+          subject.bubble_merge
+        }.to raise_error(/PR HEAD 5678 did not match test-branch HEAD 1234/)
+        expect(subject).to have_received(:sleep).exactly(5).times
+      end
+
+      it 'recovers if the PR updates to match the branch' do
+        allow(pull_request_head).to receive(:sha).and_return('5678', '1234')
+
+        subject.bubble_merge
+
+        expect(subject).to have_received(:sleep).once
+      end
+    end
+
     context 'when the repository auto deletes branches on merge' do
       let(:repository) { double(delete_branch_on_merge: true) }