diff --git a/examples/user-repositories-compare-commits-async.php b/examples/user-repositories-compare-commits-async.php
new file mode 100644
index 0000000000..ce08c4289b
--- /dev/null
+++ b/examples/user-repositories-compare-commits-async.php
@@ -0,0 +1,33 @@
+<?php declare(strict_types=1);
+use ApiClients\Client\Github\AsyncClient;
+use ApiClients\Client\Github\Resource\Async\Repository;
+use ApiClients\Client\Github\Resource\Async\User;
+use function ApiClients\Foundation\resource_pretty_print;
+use React\EventLoop\Factory;
+use function React\Promise\all;
+
+require \dirname(__DIR__) . \DIRECTORY_SEPARATOR . 'vendor/autoload.php';
+
+$loop = Factory::create();
+
+$client = AsyncClient::create($loop, require 'resolve_token.php');
+
+$client->user($argv[1] ?? 'php-api-clients')->then(function (User $user) use ($argv) {
+    resource_pretty_print($user);
+
+    return $user->repository($argv[2] ?? 'github');
+})->then(function (Repository $repository) {
+    resource_pretty_print($repository, 1, true);
+    $repository->compareCommits($argv[3] ?? '1434d8af925bc7f487005595a791d2554102862e', $argv[4] ?? 'HEAD')->then(function (Repository\Compare $compare) {
+        resource_pretty_print($compare, 2, true);
+        $compare->refresh()->then(function (Repository\Compare $compare) {
+            resource_pretty_print($compare, 2, true);
+        })->done(null, 'display_throwable');
+    }, function ($error) {
+        echo (string)$error;
+    });
+})->done(null, 'display_throwable');
+
+$loop->run();
+
+displayState($client->getRateLimitState());
diff --git a/src/CommandBus/Command/Repository/CompareCommitsCommand.php b/src/CommandBus/Command/Repository/CompareCommitsCommand.php
new file mode 100644
index 0000000000..837a384671
--- /dev/null
+++ b/src/CommandBus/Command/Repository/CompareCommitsCommand.php
@@ -0,0 +1,54 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\CommandBus\Command\Repository;
+
+use ApiClients\Client\Github\Resource\RepositoryInterface;
+use WyriHaximus\Tactician\CommandHandler\Annotations\Handler;
+
+/**
+ * @Handler("ApiClients\Client\Github\CommandBus\Handler\Repository\CompareCommitsHandler")
+ */
+final class CompareCommitsCommand
+{
+    /**
+     * @var RepositoryInterface
+     */
+    private $repository;
+
+    /**
+     * @var string
+     */
+    private $base;
+
+    /**
+     * @var string
+     */
+    private $head;
+
+    /**
+     * @param RepositoryInterface $repository
+     * @param string $base
+     * @param string $head
+     */
+    public function __construct(RepositoryInterface $repository, string $base, string $head)
+    {
+        $this->repository = $repository;
+        $this->base = $base;
+        $this->head = $head;
+    }
+
+    public function getRepository(): RepositoryInterface
+    {
+        return $this->repository;
+    }
+
+    public function getBase(): string
+    {
+        return $this->base;
+    }
+
+    public function getHead(): string
+    {
+        return $this->head;
+    }
+}
diff --git a/src/CommandBus/Handler/Repository/CompareCommitsHandler.php b/src/CommandBus/Handler/Repository/CompareCommitsHandler.php
new file mode 100644
index 0000000000..8520791cfd
--- /dev/null
+++ b/src/CommandBus/Handler/Repository/CompareCommitsHandler.php
@@ -0,0 +1,39 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\CommandBus\Handler\Repository;
+
+use ApiClients\Client\Github\CommandBus\Command\Repository\CompareCommitsCommand;
+use ApiClients\Client\Github\Resource\Repository\CompareInterface;
+use ApiClients\Tools\Services\Client\FetchAndHydrateService;
+use React\Promise\PromiseInterface;
+
+final class CompareCommitsHandler
+{
+    /**
+     * @var FetchAndHydrateService
+     */
+    private $service;
+
+    /**
+     * @param FetchAndHydrateService $service
+     */
+    public function __construct(FetchAndHydrateService $service)
+    {
+        $this->service = $service;
+    }
+
+    /**
+     * Fetch the given repository and hydrate it.
+     *
+     * @param  CompareCommitsCommand $command
+     * @return PromiseInterface
+     */
+    public function handle(CompareCommitsCommand $command): PromiseInterface
+    {
+        return $this->service->fetch(
+            'repos/' . $command->getRepository()->fullName() . '/compare/' . $command->getBase() . '...' . $command->getHead(),
+            '',
+            CompareInterface::HYDRATE_CLASS
+        );
+    }
+}
diff --git a/src/Resource/Async/Repository.php b/src/Resource/Async/Repository.php
index b9a6804992..f29d0a2c58 100644
--- a/src/Resource/Async/Repository.php
+++ b/src/Resource/Async/Repository.php
@@ -11,6 +11,7 @@
 use ApiClients\Client\Github\CommandBus\Command\Repository\CommitCommand;
 use ApiClients\Client\Github\CommandBus\Command\Repository\CommitsCommand;
 use ApiClients\Client\Github\CommandBus\Command\Repository\CommunityHealthCommand;
+use ApiClients\Client\Github\CommandBus\Command\Repository\CompareCommitsCommand;
 use ApiClients\Client\Github\CommandBus\Command\Repository\Contents\FileUploadCommand;
 use ApiClients\Client\Github\CommandBus\Command\Repository\ContentsCommand;
 use ApiClients\Client\Github\CommandBus\Command\Repository\DetailedCommitCommand;
@@ -146,6 +147,11 @@ public function pullRequests(): ObservableInterface
         ));
     }
 
+    public function compareCommits(string $base, string $head): PromiseInterface
+    {
+        return $this->handleCommand(new CompareCommitsCommand($this, $base, $head));
+    }
+
     public function addWebHook(
         string $name,
         array $config,
diff --git a/src/Resource/Async/Repository/Compare.php b/src/Resource/Async/Repository/Compare.php
new file mode 100644
index 0000000000..3f35576540
--- /dev/null
+++ b/src/Resource/Async/Repository/Compare.php
@@ -0,0 +1,15 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Async\Repository;
+
+use ApiClients\Client\Github\CommandBus\Command\RefreshCommand;
+use ApiClients\Client\Github\Resource\Repository\Compare as BaseCompare;
+use React\Promise\PromiseInterface;
+
+class Compare extends BaseCompare
+{
+    public function refresh(): PromiseInterface
+    {
+        return $this->handleCommand(new RefreshCommand($this));
+    }
+}
diff --git a/src/Resource/Async/Repository/EmptyCompare.php b/src/Resource/Async/Repository/EmptyCompare.php
new file mode 100644
index 0000000000..ce670b4f45
--- /dev/null
+++ b/src/Resource/Async/Repository/EmptyCompare.php
@@ -0,0 +1,9 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Async\Repository;
+
+use ApiClients\Client\Github\Resource\Repository\EmptyCompare as BaseEmptyCompare;
+
+class EmptyCompare extends BaseEmptyCompare
+{
+}
diff --git a/src/Resource/Repository/Compare.php b/src/Resource/Repository/Compare.php
new file mode 100644
index 0000000000..4784698634
--- /dev/null
+++ b/src/Resource/Repository/Compare.php
@@ -0,0 +1,139 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Repository;
+
+use ApiClients\Foundation\Hydrator\Annotation\Collection;
+use ApiClients\Foundation\Hydrator\Annotation\EmptyResource;
+use ApiClients\Foundation\Hydrator\Annotation\Nested;
+use ApiClients\Foundation\Resource\AbstractResource;
+
+/**
+ * @Collection(
+ *     commits="Repository\Commit",
+ *     files="Repository\Commit\File"
+ * )
+ * @Nested(
+ *     base_commit="Repository\Commit",
+ *     merge_base_commit="Repository\Commit"
+ * )
+ * @EmptyResource("Repository\EmptyCompare")
+ */
+abstract class Compare extends AbstractResource implements CompareInterface
+{
+    /**
+     * @var string
+     */
+    protected $url;
+
+    /**
+     * @var Repository\Commit
+     */
+    protected $base_commit;
+
+    /**
+     * @var Repository\Commit
+     */
+    protected $merge_base_commit;
+
+    /**
+     * @var string
+     */
+    protected $status;
+
+    /**
+     * @var int
+     */
+    protected $ahead_by;
+
+    /**
+     * @var int
+     */
+    protected $behind_by;
+
+    /**
+     * @var int
+     */
+    protected $total_commits;
+
+    /**
+     * @var Repository\Commit
+     */
+    protected $commits;
+
+    /**
+     * @var Repository\Commit\File
+     */
+    protected $files;
+
+    /**
+     * @return string
+     */
+    public function url(): string
+    {
+        return $this->url;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function baseCommit(): Repository\Commit
+    {
+        return $this->base_commit;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function mergeBaseCommit(): Repository\Commit
+    {
+        return $this->merge_base_commit;
+    }
+
+    /**
+     * @return string
+     */
+    public function status(): string
+    {
+        return $this->status;
+    }
+
+    /**
+     * @return int
+     */
+    public function aheadBy(): int
+    {
+        return $this->ahead_by;
+    }
+
+    /**
+     * @return int
+     */
+    public function behindBy(): int
+    {
+        return $this->behind_by;
+    }
+
+    /**
+     * @return int
+     */
+    public function totalCommits(): int
+    {
+        return $this->total_commits;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function commits(): Repository\Commit
+    {
+        return $this->commits;
+    }
+
+    /**
+     * @return Repository\Commit\File
+     */
+    public function files(): Repository\Commit\File
+    {
+        return $this->files;
+    }
+}
diff --git a/src/Resource/Repository/CompareInterface.php b/src/Resource/Repository/CompareInterface.php
new file mode 100644
index 0000000000..f4e71cc5bf
--- /dev/null
+++ b/src/Resource/Repository/CompareInterface.php
@@ -0,0 +1,55 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Repository;
+
+use ApiClients\Foundation\Resource\ResourceInterface;
+
+interface CompareInterface extends ResourceInterface
+{
+    const HYDRATE_CLASS = 'Repository\\Compare';
+
+    /**
+     * @return string
+     */
+    public function url(): string;
+
+    /**
+     * @return Repository\Commit
+     */
+    public function baseCommit(): Repository\Commit;
+
+    /**
+     * @return Repository\Commit
+     */
+    public function mergeBaseCommit(): Repository\Commit;
+
+    /**
+     * @return string
+     */
+    public function status(): string;
+
+    /**
+     * @return int
+     */
+    public function aheadBy(): int;
+
+    /**
+     * @return int
+     */
+    public function behindBy(): int;
+
+    /**
+     * @return int
+     */
+    public function totalCommits(): int;
+
+    /**
+     * @return Repository\Commit
+     */
+    public function commits(): Repository\Commit;
+
+    /**
+     * @return Repository\Commit\File
+     */
+    public function files(): Repository\Commit\File;
+}
diff --git a/src/Resource/Repository/EmptyCompare.php b/src/Resource/Repository/EmptyCompare.php
new file mode 100644
index 0000000000..6a3e2b0631
--- /dev/null
+++ b/src/Resource/Repository/EmptyCompare.php
@@ -0,0 +1,80 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Repository;
+
+use ApiClients\Foundation\Resource\EmptyResourceInterface;
+
+abstract class EmptyCompare implements CompareInterface, EmptyResourceInterface
+{
+    /**
+     * @return string
+     */
+    public function url(): string
+    {
+        return null;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function baseCommit(): Repository\Commit
+    {
+        return null;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function mergeBaseCommit(): Repository\Commit
+    {
+        return null;
+    }
+
+    /**
+     * @return string
+     */
+    public function status(): string
+    {
+        return null;
+    }
+
+    /**
+     * @return int
+     */
+    public function aheadBy(): int
+    {
+        return null;
+    }
+
+    /**
+     * @return int
+     */
+    public function behindBy(): int
+    {
+        return null;
+    }
+
+    /**
+     * @return int
+     */
+    public function totalCommits(): int
+    {
+        return null;
+    }
+
+    /**
+     * @return Repository\Commit
+     */
+    public function commits(): Repository\Commit
+    {
+        return null;
+    }
+
+    /**
+     * @return Repository\Commit\File
+     */
+    public function files(): Repository\Commit\File
+    {
+        return null;
+    }
+}
diff --git a/src/Resource/Sync/Repository/Compare.php b/src/Resource/Sync/Repository/Compare.php
new file mode 100644
index 0000000000..87f26d498d
--- /dev/null
+++ b/src/Resource/Sync/Repository/Compare.php
@@ -0,0 +1,17 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Sync\Repository;
+
+use ApiClients\Client\Github\Resource\Repository\Compare as BaseCompare;
+use ApiClients\Client\Github\Resource\Repository\CompareInterface;
+use ApiClients\Foundation\Hydrator\CommandBus\Command\BuildAsyncFromSyncCommand;
+
+class Compare extends BaseCompare
+{
+    public function refresh(): Compare
+    {
+        return $this->wait($this->handleCommand(new BuildAsyncFromSyncCommand(self::HYDRATE_CLASS, $this))->then(function (CompareInterface $compare) {
+            return $compare->refresh();
+        }));
+    }
+}
diff --git a/src/Resource/Sync/Repository/EmptyCompare.php b/src/Resource/Sync/Repository/EmptyCompare.php
new file mode 100644
index 0000000000..2bba6f48bc
--- /dev/null
+++ b/src/Resource/Sync/Repository/EmptyCompare.php
@@ -0,0 +1,9 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Client\Github\Resource\Sync\Repository;
+
+use ApiClients\Client\Github\Resource\Repository\EmptyCompare as BaseEmptyCompare;
+
+class EmptyCompare extends BaseEmptyCompare
+{
+}
diff --git a/tests/Resource/Async/Repository/CompareTest.php b/tests/Resource/Async/Repository/CompareTest.php
new file mode 100644
index 0000000000..a78fbe9739
--- /dev/null
+++ b/tests/Resource/Async/Repository/CompareTest.php
@@ -0,0 +1,25 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Tests\Client\Github\Resource\Async\Repository;
+
+use ApiClients\Client\Github\ApiSettings;
+use ApiClients\Client\Github\Resource\Repository\Compare;
+use ApiClients\Tools\ResourceTestUtilities\AbstractResourceTest;
+
+class CompareTest extends AbstractResourceTest
+{
+    public function getSyncAsync(): string
+    {
+        return 'Async';
+    }
+
+    public function getClass(): string
+    {
+        return Compare::class;
+    }
+
+    public function getNamespace(): string
+    {
+        return ApiSettings::NAMESPACE;
+    }
+}
diff --git a/tests/Resource/Async/Repository/EmptyCompareTest.php b/tests/Resource/Async/Repository/EmptyCompareTest.php
new file mode 100644
index 0000000000..63c95ba650
--- /dev/null
+++ b/tests/Resource/Async/Repository/EmptyCompareTest.php
@@ -0,0 +1,19 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Tests\Client\Github\Resource\Async\Repository;
+
+use ApiClients\Client\Github\Resource\Async\Repository\EmptyCompare;
+use ApiClients\Tools\ResourceTestUtilities\AbstractEmptyResourceTest;
+
+final class EmptyCompareTest extends AbstractEmptyResourceTest
+{
+    public function getSyncAsync(): string
+    {
+        return 'Async';
+    }
+
+    public function getClass(): string
+    {
+        return EmptyCompare::class;
+    }
+}
diff --git a/tests/Resource/Sync/Repository/CompareTest.php b/tests/Resource/Sync/Repository/CompareTest.php
new file mode 100644
index 0000000000..63a5aee9f6
--- /dev/null
+++ b/tests/Resource/Sync/Repository/CompareTest.php
@@ -0,0 +1,25 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Tests\Client\Github\Resource\Sync\Repository;
+
+use ApiClients\Client\Github\ApiSettings;
+use ApiClients\Client\Github\Resource\Repository\Compare;
+use ApiClients\Tools\ResourceTestUtilities\AbstractResourceTest;
+
+class CompareTest extends AbstractResourceTest
+{
+    public function getSyncAsync(): string
+    {
+        return 'Sync';
+    }
+
+    public function getClass(): string
+    {
+        return Compare::class;
+    }
+
+    public function getNamespace(): string
+    {
+        return ApiSettings::NAMESPACE;
+    }
+}
diff --git a/tests/Resource/Sync/Repository/EmptyCompareTest.php b/tests/Resource/Sync/Repository/EmptyCompareTest.php
new file mode 100644
index 0000000000..55e7b2cb79
--- /dev/null
+++ b/tests/Resource/Sync/Repository/EmptyCompareTest.php
@@ -0,0 +1,19 @@
+<?php declare(strict_types=1);
+
+namespace ApiClients\Tests\Client\Github\Resource\Sync\Repository;
+
+use ApiClients\Client\Github\Resource\Sync\Repository\EmptyCompare;
+use ApiClients\Tools\ResourceTestUtilities\AbstractEmptyResourceTest;
+
+final class EmptyCompareTest extends AbstractEmptyResourceTest
+{
+    public function getSyncAsync(): string
+    {
+        return 'Sync';
+    }
+
+    public function getClass(): string
+    {
+        return EmptyCompare::class;
+    }
+}
diff --git a/yaml/repository-compare.yml b/yaml/repository-compare.yml
new file mode 100644
index 0000000000..4eb665ae80
--- /dev/null
+++ b/yaml/repository-compare.yml
@@ -0,0 +1,23 @@
+class: Repository\Compare
+properties:
+  url: string
+  base_commit:
+      type: Repository\Commit
+      annotations:
+          nested: Repository\Commit
+  merge_base_commit:
+      type: Repository\Commit
+      annotations:
+          nested: Repository\Commit
+  status: string
+  ahead_by: int
+  behind_by: int
+  total_commits: int
+  commits:
+      type: Repository\Commit
+      annotations:
+          collection: Repository\Commit
+  files:
+      type: Repository\Commit\File
+      annotations:
+          collection: Repository\Commit\File