diff --git a/core/tests/BasePageTest.php b/core/tests/BasePageTest.php
index fdec72c1..922bc6a5 100644
--- a/core/tests/BasePageTest.php
+++ b/core/tests/BasePageTest.php
@@ -10,7 +10,7 @@ require_once "core/basepage.php";
 
 class BasePageTest extends TestCase
 {
-    public function test_page()
+    public function test_page(): void
     {
         $page = new BasePage();
         $page->set_mode(PageMode::PAGE);
@@ -20,7 +20,7 @@ class BasePageTest extends TestCase
         $this->assertTrue(true);  // doesn't crash
     }
 
-    public function test_file()
+    public function test_file(): void
     {
         $page = new BasePage();
         $page->set_mode(PageMode::FILE);
@@ -31,7 +31,7 @@ class BasePageTest extends TestCase
         $this->assertTrue(true);  // doesn't crash
     }
 
-    public function test_data()
+    public function test_data(): void
     {
         $page = new BasePage();
         $page->set_mode(PageMode::DATA);
@@ -42,7 +42,7 @@ class BasePageTest extends TestCase
         $this->assertTrue(true);  // doesn't crash
     }
 
-    public function test_redirect()
+    public function test_redirect(): void
     {
         $page = new BasePage();
         $page->set_mode(PageMode::REDIRECT);
diff --git a/core/tests/BlockTest.php b/core/tests/BlockTest.php
index 1051e773..b8ae0b78 100644
--- a/core/tests/BlockTest.php
+++ b/core/tests/BlockTest.php
@@ -10,7 +10,7 @@ require_once "core/block.php";
 
 class BlockTest extends TestCase
 {
-    public function test_basic()
+    public function test_basic(): void
     {
         $b = new Block("head", "body");
         $this->assertEquals(
diff --git a/core/tests/InitTest.php b/core/tests/InitTest.php
index 3fc48857..8cb5965e 100644
--- a/core/tests/InitTest.php
+++ b/core/tests/InitTest.php
@@ -8,13 +8,13 @@ use PHPUnit\Framework\TestCase;
 
 class InitTest extends TestCase
 {
-    public function testInitExt()
+    public function testInitExt(): void
     {
         send_event(new InitExtEvent());
         $this->assertTrue(true);
     }
 
-    public function testDatabaseUpgrade()
+    public function testDatabaseUpgrade(): void
     {
         send_event(new DatabaseUpgradeEvent());
         $this->assertTrue(true);
diff --git a/core/tests/PolyfillsTest.php b/core/tests/PolyfillsTest.php
index fc73a30b..2ca5328f 100644
--- a/core/tests/PolyfillsTest.php
+++ b/core/tests/PolyfillsTest.php
@@ -10,7 +10,7 @@ require_once "core/polyfills.php";
 
 class PolyfillsTest extends TestCase
 {
-    public function test_html_escape()
+    public function test_html_escape(): void
     {
         $this->assertEquals(
             "Foo & <main>",
@@ -26,7 +26,7 @@ class PolyfillsTest extends TestCase
         $this->assertEquals(html_escape(html_unescape($x)), $x);
     }
 
-    public function test_int_escape()
+    public function test_int_escape(): void
     {
         $this->assertEquals(0, int_escape(""));
         $this->assertEquals(1, int_escape("1"));
@@ -35,13 +35,13 @@ class PolyfillsTest extends TestCase
         $this->assertEquals(0, int_escape(null));
     }
 
-    public function test_url_escape()
+    public function test_url_escape(): void
     {
         $this->assertEquals("%5E%5Co%2F%5E", url_escape("^\o/^"));
         $this->assertEquals("", url_escape(null));
     }
 
-    public function test_bool_escape()
+    public function test_bool_escape(): void
     {
         $this->assertTrue(bool_escape(true));
         $this->assertFalse(bool_escape(false));
@@ -71,7 +71,7 @@ class PolyfillsTest extends TestCase
         $this->assertFalse(bool_escape("0"));
     }
 
-    public function test_clamp()
+    public function test_clamp(): void
     {
         $this->assertEquals(5, clamp(0, 5, 10)); // too small
         $this->assertEquals(5, clamp(5, 5, 10)); // lower limit
@@ -83,7 +83,7 @@ class PolyfillsTest extends TestCase
         $this->assertEquals(42, clamp(42, null, null)); // no limit
     }
 
-    public function test_truncate()
+    public function test_truncate(): void
     {
         $this->assertEquals("test words", truncate("test words", 10));
         $this->assertEquals("test...", truncate("test...", 9));
@@ -91,7 +91,7 @@ class PolyfillsTest extends TestCase
         $this->assertEquals("te...", truncate("te...", 2));
     }
 
-    public function test_to_shorthand_int()
+    public function test_to_shorthand_int(): void
     {
         // 0-9 should have 1 decimal place, 10+ should have none
         $this->assertEquals("1.1GB", to_shorthand_int(1231231231));
@@ -100,7 +100,7 @@ class PolyfillsTest extends TestCase
         $this->assertEquals("2", to_shorthand_int(2));
     }
 
-    public function test_parse_shorthand_int()
+    public function test_parse_shorthand_int(): void
     {
         $this->assertEquals(-1, parse_shorthand_int("foo"));
         $this->assertEquals(33554432, parse_shorthand_int("32M"));
@@ -108,21 +108,21 @@ class PolyfillsTest extends TestCase
         $this->assertEquals(1231231231, parse_shorthand_int("1231231231"));
     }
 
-    public function test_format_milliseconds()
+    public function test_format_milliseconds(): void
     {
         $this->assertEquals("", format_milliseconds(5));
         $this->assertEquals("5s", format_milliseconds(5000));
         $this->assertEquals("1y 213d 16h 53m 20s", format_milliseconds(50000000000));
     }
 
-    public function test_parse_to_milliseconds()
+    public function test_parse_to_milliseconds(): void
     {
         $this->assertEquals(10, parse_to_milliseconds("10"));
         $this->assertEquals(5000, parse_to_milliseconds("5s"));
         $this->assertEquals(50000000000, parse_to_milliseconds("1y 213d 16h 53m 20s"));
     }
 
-    public function test_autodate()
+    public function test_autodate(): void
     {
         $this->assertEquals(
             "<time datetime='2012-06-23T16:14:22+00:00'>June 23, 2012; 16:14</time>",
@@ -130,7 +130,7 @@ class PolyfillsTest extends TestCase
         );
     }
 
-    public function test_validate_input()
+    public function test_validate_input(): void
     {
         $_POST = [
             "foo" => " bar ",
@@ -151,7 +151,7 @@ class PolyfillsTest extends TestCase
         );
     }
 
-    public function test_sanitize_path()
+    public function test_sanitize_path(): void
     {
         $this->assertEquals(
             "one",
@@ -194,7 +194,7 @@ class PolyfillsTest extends TestCase
         );
     }
 
-    public function test_join_path()
+    public function test_join_path(): void
     {
         $this->assertEquals(
             "one",
@@ -222,7 +222,7 @@ class PolyfillsTest extends TestCase
         );
     }
 
-    public function test_stringer()
+    public function test_stringer(): void
     {
         $this->assertEquals(
             '["foo"=>"bar", "baz"=>[1, 2, 3], "qux"=>["a"=>"b"]]',
@@ -230,7 +230,7 @@ class PolyfillsTest extends TestCase
         );
     }
 
-    public function test_ip_in_range()
+    public function test_ip_in_range(): void
     {
         $this->assertTrue(ip_in_range("1.2.3.4", "1.2.0.0/16"));
         $this->assertFalse(ip_in_range("4.3.2.1", "1.2.0.0/16"));
@@ -239,7 +239,7 @@ class PolyfillsTest extends TestCase
         $this->assertTrue(ip_in_range("1.2.3.4", "1.2.3.4"));
     }
 
-    public function test_deltree()
+    public function test_deltree(): void
     {
         $tmp = sys_get_temp_dir();
         $dir = "$tmp/test_deltree";
diff --git a/core/tests/SearchTest.php b/core/tests/SearchTest.php
index c95197d7..633610c0 100644
--- a/core/tests/SearchTest.php
+++ b/core/tests/SearchTest.php
@@ -11,7 +11,7 @@ require_once "core/imageboard/search.php";
 
 class SearchTest extends ShimmiePHPUnitTestCase
 {
-    public function testWeirdTags()
+    public function testWeirdTags(): void
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "question? colon:thing exclamation!");
@@ -67,7 +67,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testTTC_Empty()
+    public function testTTC_Empty(): void
     {
         $this->assert_TTC(
             "",
@@ -84,7 +84,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testTTC_Hash()
+    public function testTTC_Hash(): void
     {
         $this->assert_TTC(
             "hash=1234567890",
@@ -102,7 +102,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testTTC_Ratio()
+    public function testTTC_Ratio(): void
     {
         $this->assert_TTC(
             "ratio=42:12345",
@@ -121,7 +121,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testTTC_Order()
+    public function testTTC_Order(): void
     {
         $this->assert_TTC(
             "order=score",
@@ -192,7 +192,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     * No-tag search      *
     * * * * * * * * * * */
     #[Depends('testUpload')]
-    public function testBSQ_NoTags($image_ids)
+    public function testBSQ_NoTags($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -206,7 +206,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     * Fast-path search   *
     * * * * * * * * * * */
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_NoResults($image_ids)
+    public function testBSQ_FastPath_NoResults($image_ids): void
     {
         $this->testUpload();
         $this->assert_BSQ(
@@ -217,7 +217,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_OneResult($image_ids)
+    public function testBSQ_FastPath_OneResult($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -228,7 +228,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_ManyResults($image_ids)
+    public function testBSQ_FastPath_ManyResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -239,7 +239,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_WildNoResults($image_ids)
+    public function testBSQ_FastPath_WildNoResults($image_ids): void
     {
         $this->testUpload();
         $this->assert_BSQ(
@@ -258,7 +258,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
      * https://github.com/shish/shimmie2/issues/547
      */
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_WildOneResult($image_ids)
+    public function testBSQ_FastPath_WildOneResult($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -273,7 +273,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
      * when a wildcard matches one image multiple times.
      */
     #[Depends('testUpload')]
-    public function testBSQ_FastPath_WildManyResults($image_ids)
+    public function testBSQ_FastPath_WildManyResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         // two images match comp* - one matches it once, one matches it twice
@@ -288,7 +288,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     * General search     *
     * * * * * * * * * * */
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_NoResults($image_ids)
+    public function testBSQ_GeneralPath_NoResults($image_ids): void
     {
         $this->testUpload();
         # multiple tags, one of which doesn't exist
@@ -301,7 +301,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_OneResult($image_ids)
+    public function testBSQ_GeneralPath_OneResult($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -320,7 +320,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
      * https://github.com/shish/shimmie2/issues/547
      */
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_WildOneResult($image_ids)
+    public function testBSQ_GeneralPath_WildOneResult($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -331,7 +331,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_ManyResults($image_ids)
+    public function testBSQ_GeneralPath_ManyResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -342,7 +342,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_WildManyResults($image_ids)
+    public function testBSQ_GeneralPath_WildManyResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -353,7 +353,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_SubtractValidFromResults($image_ids)
+    public function testBSQ_GeneralPath_SubtractValidFromResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -364,7 +364,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_SubtractNotValidFromResults($image_ids)
+    public function testBSQ_GeneralPath_SubtractNotValidFromResults($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -375,7 +375,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_SubtractValidFromDefault($image_ids)
+    public function testBSQ_GeneralPath_SubtractValidFromDefault($image_ids): void
     {
         $image_ids = $this->testUpload();
         // negative tag alone, should remove the image with that tag
@@ -387,7 +387,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_SubtractNotValidFromDefault($image_ids)
+    public function testBSQ_GeneralPath_SubtractNotValidFromDefault($image_ids): void
     {
         $image_ids = $this->testUpload();
         // negative that doesn't exist, should return all results
@@ -399,7 +399,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_GeneralPath_SubtractMultipleNotValidFromDefault($image_ids)
+    public function testBSQ_GeneralPath_SubtractMultipleNotValidFromDefault($image_ids): void
     {
         $image_ids = $this->testUpload();
         // multiple negative tags that don't exist, should return all results
@@ -414,7 +414,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     * Meta Search        *
     * * * * * * * * * * */
     #[Depends('testUpload')]
-    public function testBSQ_ImgCond_NoResults($image_ids)
+    public function testBSQ_ImgCond_NoResults($image_ids): void
     {
         $this->testUpload();
         $this->assert_BSQ(
@@ -430,7 +430,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_ImgCond_OneResult($image_ids)
+    public function testBSQ_ImgCond_OneResult($image_ids): void
     {
         $image_ids = $this->testUpload();
         $this->assert_BSQ(
@@ -451,7 +451,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testUpload')]
-    public function testBSQ_ImgCond_ManyResults($image_ids)
+    public function testBSQ_ImgCond_ManyResults($image_ids): void
     {
         $image_ids = $this->testUpload();
 
@@ -476,7 +476,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
     * Mixed              *
     * * * * * * * * * * */
     #[Depends('testUpload')]
-    public function testBSQ_TagCondWithImgCond($image_ids)
+    public function testBSQ_TagCondWithImgCond($image_ids): void
     {
         $image_ids = $this->testUpload();
         // multiple tags, many results
@@ -492,7 +492,7 @@ class SearchTest extends ShimmiePHPUnitTestCase
      * get_images
      */
     #[Depends('testUpload')]
-    public function test_get_images()
+    public function test_get_images(): void
     {
         $image_ids = $this->testUpload();
 
diff --git a/core/tests/TagTest.php b/core/tests/TagTest.php
index de928898..a678e406 100644
--- a/core/tests/TagTest.php
+++ b/core/tests/TagTest.php
@@ -10,7 +10,7 @@ require_once "core/imageboard/tag.php";
 
 class TagTest extends TestCase
 {
-    public function test_compare()
+    public function test_compare(): void
     {
         $this->assertFalse(Tag::compare(["foo"], ["bar"]));
         $this->assertFalse(Tag::compare(["foo"], ["foo", "bar"]));
diff --git a/core/tests/UrlsTest.php b/core/tests/UrlsTest.php
index 2d8c8e10..918d4dbc 100644
--- a/core/tests/UrlsTest.php
+++ b/core/tests/UrlsTest.php
@@ -10,7 +10,7 @@ require_once "core/urls.php";
 
 class UrlsTest extends TestCase
 {
-    public function test_search_link()
+    public function test_search_link(): void
     {
         $this->assertEquals(
             "/test/post/list/bar%20foo/1",
@@ -22,7 +22,7 @@ class UrlsTest extends TestCase
         );
     }
 
-    public function test_make_link()
+    public function test_make_link(): void
     {
         // basic
         $this->assertEquals(
@@ -55,7 +55,7 @@ class UrlsTest extends TestCase
         );
     }
 
-    public function test_make_http()
+    public function test_make_http(): void
     {
         // relative to shimmie install
         $this->assertEquals(
@@ -76,7 +76,7 @@ class UrlsTest extends TestCase
         );
     }
 
-    public function test_modify_url()
+    public function test_modify_url(): void
     {
         $this->assertEquals(
             "/foo/bar?a=3&b=2",
@@ -94,7 +94,7 @@ class UrlsTest extends TestCase
         );
     }
 
-    public function test_referer_or()
+    public function test_referer_or(): void
     {
         unset($_SERVER['HTTP_REFERER']);
         $this->assertEquals(
diff --git a/core/tests/UtilTest.php b/core/tests/UtilTest.php
index e4312307..d622cc2d 100644
--- a/core/tests/UtilTest.php
+++ b/core/tests/UtilTest.php
@@ -10,42 +10,42 @@ require_once "core/util.php";
 
 class UtilTest extends TestCase
 {
-    public function test_get_theme()
+    public function test_get_theme(): void
     {
         $this->assertEquals("default", get_theme());
     }
 
-    public function test_get_memory_limit()
+    public function test_get_memory_limit(): void
     {
         get_memory_limit();
         $this->assertTrue(true);
     }
 
-    public function test_check_gd_version()
+    public function test_check_gd_version(): void
     {
         check_gd_version();
         $this->assertTrue(true);
     }
 
-    public function test_check_im_version()
+    public function test_check_im_version(): void
     {
         check_im_version();
         $this->assertTrue(true);
     }
 
-    public function test_human_filesize()
+    public function test_human_filesize(): void
     {
         $this->assertEquals("123.00B", human_filesize(123));
         $this->assertEquals("123B", human_filesize(123, 0));
         $this->assertEquals("120.56KB", human_filesize(123456));
     }
 
-    public function test_generate_key()
+    public function test_generate_key(): void
     {
         $this->assertEquals(20, strlen(generate_key()));
     }
 
-    public function test_warehouse_path()
+    public function test_warehouse_path(): void
     {
         $hash = "7ac19c10d6859415";
 
@@ -105,7 +105,7 @@ class UtilTest extends TestCase
         );
     }
 
-    public function test_load_balance_url()
+    public function test_load_balance_url(): void
     {
         $hash = "7ac19c10d6859415";
         $ext = "jpg";
@@ -123,7 +123,7 @@ class UtilTest extends TestCase
         );
     }
 
-    public function test_path_to_tags()
+    public function test_path_to_tags(): void
     {
         $this->assertEquals(
             [],
diff --git a/core/util.php b/core/util.php
index e52acf4c..0e6c81c4 100644
--- a/core/util.php
+++ b/core/util.php
@@ -163,7 +163,7 @@ function is_trusted_proxy(): bool
 /**
  * Get real IP if behind a reverse proxy
  */
-function get_real_ip()
+function get_real_ip(): string
 {
     $ip = $_SERVER['REMOTE_ADDR'];
 
@@ -572,7 +572,7 @@ function require_all(array $files): void
     }
 }
 
-function _load_core_files()
+function _load_core_files(): void
 {
     require_all(array_merge(
         zglob("core/*.php"),
@@ -581,14 +581,14 @@ function _load_core_files()
     ));
 }
 
-function _load_extension_files()
+function _load_extension_files(): void
 {
     ExtensionInfo::load_all_extension_info();
     Extension::determine_enabled_extensions();
     require_all(zglob("ext/{".Extension::get_enabled_extensions_as_string()."}/main.php"));
 }
 
-function _load_theme_files()
+function _load_theme_files(): void
 {
     $theme = get_theme();
     require_once('themes/'.$theme.'/page.class.php');
@@ -770,7 +770,7 @@ function make_form(string $target, string $method = "POST", bool $multipart = fa
 }
 
 const BYTE_DENOMINATIONS = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
-function human_filesize(int $bytes, $decimals = 2): string
+function human_filesize(int $bytes, int $decimals = 2): string
 {
     $factor = floor((strlen(strval($bytes)) - 1) / 3);
     return sprintf("%.{$decimals}f", $bytes / pow(1024, $factor)) . @BYTE_DENOMINATIONS[$factor];
diff --git a/ext/admin/test.php b/ext/admin/test.php
index 3b59bf82..6975d1e8 100644
--- a/ext/admin/test.php
+++ b/ext/admin/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class AdminPageTest extends ShimmiePHPUnitTestCase
 {
-    public function testAuth()
+    public function testAuth(): void
     {
         send_event(new UserLoginEvent(User::by_name(self::$anon_name)));
         $page = $this->get_page('admin');
diff --git a/ext/alias_editor/test.php b/ext/alias_editor/test.php
index 78437026..55522cde 100644
--- a/ext/alias_editor/test.php
+++ b/ext/alias_editor/test.php
@@ -6,14 +6,14 @@ namespace Shimmie2;
 
 class AliasEditorTest extends ShimmiePHPUnitTestCase
 {
-    public function testAliasList()
+    public function testAliasList(): void
     {
         $this->get_page('alias/list');
         $this->assert_response(200);
         $this->assert_title("Alias List");
     }
 
-    public function testAliasListReadOnly()
+    public function testAliasListReadOnly(): void
     {
         $this->log_in_as_user();
         $this->get_page('alias/list');
@@ -26,7 +26,7 @@ class AliasEditorTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("Add");
     }
 
-    public function testAliasOneToOne()
+    public function testAliasOneToOne(): void
     {
         $this->log_in_as_admin();
 
@@ -54,7 +54,7 @@ class AliasEditorTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("test1");
     }
 
-    public function testAliasOneToMany()
+    public function testAliasOneToMany(): void
     {
         $this->log_in_as_admin();
 
diff --git a/ext/artists/test.php b/ext/artists/test.php
index 47f312bd..36bdaed8 100644
--- a/ext/artists/test.php
+++ b/ext/artists/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ArtistsTest extends ShimmiePHPUnitTestCase
 {
-    public function testSearch()
+    public function testSearch(): void
     {
         global $user;
         $this->log_in_as_user();
diff --git a/ext/auto_tagger/test.php b/ext/auto_tagger/test.php
index e8ed6293..49ca03fe 100644
--- a/ext/auto_tagger/test.php
+++ b/ext/auto_tagger/test.php
@@ -6,14 +6,14 @@ namespace Shimmie2;
 
 class AutoTaggerTest extends ShimmiePHPUnitTestCase
 {
-    public function testAutoTaggerList()
+    public function testAutoTaggerList(): void
     {
         $this->get_page('auto_tag/list');
         $this->assert_response(200);
         $this->assert_title("Auto-Tag");
     }
 
-    public function testAutoTaggerListReadOnly()
+    public function testAutoTaggerListReadOnly(): void
     {
         $this->log_in_as_user();
         $this->get_page('auto_tag/list');
@@ -26,7 +26,7 @@ class AutoTaggerTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("value=\"Add\"");
     }
 
-    public function testAutoTagger()
+    public function testAutoTagger(): void
     {
         $this->log_in_as_admin();
 
diff --git a/ext/autocomplete/test.php b/ext/autocomplete/test.php
index ff82aa63..6f92370a 100644
--- a/ext/autocomplete/test.php
+++ b/ext/autocomplete/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class AutoCompleteTest extends ShimmiePHPUnitTestCase
 {
-    public function testAuth()
+    public function testAuth(): void
     {
         send_event(new UserLoginEvent(User::by_name(self::$anon_name)));
         $page = $this->get_page('api/internal/autocomplete', ["s" => "not-a-tag"]);
diff --git a/ext/ban_words/test.php b/ext/ban_words/test.php
index a70f6a06..543d1e3b 100644
--- a/ext/ban_words/test.php
+++ b/ext/ban_words/test.php
@@ -17,7 +17,7 @@ class BanWordsTest extends ShimmiePHPUnitTestCase
         }
     }
 
-    public function testWordBan()
+    public function testWordBan(): void
     {
         global $config;
         $config->set_string("banned_words", "viagra\nporn\n\n/http:.*\.cn\//");
diff --git a/ext/bbcode/test.php b/ext/bbcode/test.php
index 20b42b6a..3eb2c761 100644
--- a/ext/bbcode/test.php
+++ b/ext/bbcode/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class BBCodeTest extends ShimmiePHPUnitTestCase
 {
-    public function testBasics()
+    public function testBasics(): void
     {
         $this->assertEquals(
             "<b>bold</b><i>italic</i>",
@@ -14,7 +14,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testStacking()
+    public function testStacking(): void
     {
         $this->assertEquals(
             "<b>B</b><i>I</i><b>B</b>",
@@ -26,7 +26,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testFailure()
+    public function testFailure(): void
     {
         $this->assertEquals(
             "[b]bold[i]italic",
@@ -34,7 +34,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testCode()
+    public function testCode(): void
     {
         $this->assertEquals(
             "<pre class='code'>[b]bold[/b]</pre>",
@@ -42,7 +42,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testNestedList()
+    public function testNestedList(): void
     {
         $this->assertEquals(
             "<ul><li>a<ul><li>a<li>b</ul><li>b</ul>",
@@ -54,7 +54,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testSpoiler()
+    public function testSpoiler(): void
     {
         $this->assertEquals(
             "<span style=\"background-color:#000; color:#000;\">ShishNet</span>",
@@ -69,7 +69,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         #	"[spoiler]ShishNet");
     }
 
-    public function testURL()
+    public function testURL(): void
     {
         $this->assertEquals(
             "<a href=\"https://shishnet.org\">https://shishnet.org</a>",
@@ -85,7 +85,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testEmailURL()
+    public function testEmailURL(): void
     {
         $this->assertEquals(
             "<a href=\"mailto:spam@shishnet.org\">spam@shishnet.org</a>",
@@ -93,7 +93,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testAnchor()
+    public function testAnchor(): void
     {
         $this->assertEquals(
             '<span class="anchor">Rules <a class="alink" href="#bb-rules" name="bb-rules" title="link to this anchor"> ¶ </a></span>',
@@ -113,7 +113,7 @@ class BBCodeTest extends ShimmiePHPUnitTestCase
         return $bb->strip($in);
     }
 
-    public function testSiteLinks()
+    public function testSiteLinks(): void
     {
         $this->assertEquals(
             '<a class="shm-clink" data-clink-sel="" href="/test/post/view/123">&gt;&gt;123</a>',
diff --git a/ext/biography/test.php b/ext/biography/test.php
index 700febc6..746d092f 100644
--- a/ext/biography/test.php
+++ b/ext/biography/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class BiographyTest extends ShimmiePHPUnitTestCase
 {
-    public function testBio()
+    public function testBio(): void
     {
         $this->log_in_as_user();
         $this->post_page("biography", ["biography" => "My bio goes here"]);
diff --git a/ext/blocks/test.php b/ext/blocks/test.php
index 15677c4f..03d3ff1f 100644
--- a/ext/blocks/test.php
+++ b/ext/blocks/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class BlocksTest extends ShimmiePHPUnitTestCase
 {
-    public function testBlocks()
+    public function testBlocks(): void
     {
         $this->log_in_as_admin();
         $this->get_page("blocks/list");
diff --git a/ext/blotter/test.php b/ext/blotter/test.php
index 4bd3cfdb..26797a2a 100644
--- a/ext/blotter/test.php
+++ b/ext/blotter/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class BlotterTest extends ShimmiePHPUnitTestCase
 {
-    public function testDenial()
+    public function testDenial(): void
     {
         $this->get_page("blotter/editor");
         $this->assert_response(403);
@@ -16,7 +16,7 @@ class BlotterTest extends ShimmiePHPUnitTestCase
         $this->assert_response(403);
     }
 
-    public function testAddViewRemove()
+    public function testAddViewRemove(): void
     {
         $this->log_in_as_admin();
 
diff --git a/ext/browser_search/test.php b/ext/browser_search/test.php
index 3ccd045f..c50f0d81 100644
--- a/ext/browser_search/test.php
+++ b/ext/browser_search/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class BrowserSearchTest extends ShimmiePHPUnitTestCase
 {
-    public function testBasic()
+    public function testBasic(): void
     {
         $page = $this->get_page("browser_search.xml");
         $this->assertEquals(200, $page->code);
diff --git a/ext/bulk_add/test.php b/ext/bulk_add/test.php
index da53d4e9..81425c03 100644
--- a/ext/bulk_add/test.php
+++ b/ext/bulk_add/test.php
@@ -6,14 +6,14 @@ namespace Shimmie2;
 
 class BulkAddTest extends ShimmiePHPUnitTestCase
 {
-    public function testInvalidDir()
+    public function testInvalidDir(): void
     {
         send_event(new UserLoginEvent(User::by_name(self::$admin_name)));
         $bae = send_event(new BulkAddEvent('asdf'));
         $this->assertTrue(is_a($bae->results[0], UploadError::class));
     }
 
-    public function testValidDir()
+    public function testValidDir(): void
     {
         send_event(new UserLoginEvent(User::by_name(self::$admin_name)));
         send_event(new BulkAddEvent('tests'));
diff --git a/ext/comment/test.php b/ext/comment/test.php
index 4bafa098..9d7e9fdb 100644
--- a/ext/comment/test.php
+++ b/ext/comment/test.php
@@ -21,7 +21,7 @@ class CommentListTest extends ShimmiePHPUnitTestCase
         parent::tearDown();
     }
 
-    public function testCommentsPage()
+    public function testCommentsPage(): void
     {
         global $user;
 
@@ -90,7 +90,7 @@ class CommentListTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text('ASDFASDF');
     }
 
-    public function testSingleDel()
+    public function testSingleDel(): void
     {
         global $database, $user;
 
diff --git a/ext/danbooru_api/test.php b/ext/danbooru_api/test.php
index 4b98e095..bf72e247 100644
--- a/ext/danbooru_api/test.php
+++ b/ext/danbooru_api/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class DanbooruApiTest extends ShimmiePHPUnitTestCase
 {
-    public function testSearch()
+    public function testSearch(): void
     {
         $this->log_in_as_admin();
 
diff --git a/ext/download/test.php b/ext/download/test.php
index b0ac2949..8b638502 100644
--- a/ext/download/test.php
+++ b/ext/download/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class DownloadTest extends ShimmiePHPUnitTestCase
 {
-    public function testView()
+    public function testView(): void
     {
         global $page;
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
diff --git a/ext/downtime/test.php b/ext/downtime/test.php
index 460567e7..77dfa261 100644
--- a/ext/downtime/test.php
+++ b/ext/downtime/test.php
@@ -13,7 +13,7 @@ class DowntimeTest extends ShimmiePHPUnitTestCase
         parent::tearDown();
     }
 
-    public function testDowntime()
+    public function testDowntime(): void
     {
         global $config;
 
diff --git a/ext/emoticons/test.php b/ext/emoticons/test.php
index 0bcd20ee..9606d9e2 100644
--- a/ext/emoticons/test.php
+++ b/ext/emoticons/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class EmoticonsTest extends ShimmiePHPUnitTestCase
 {
-    public function testEmoticons()
+    public function testEmoticons(): void
     {
         global $user;
 
diff --git a/ext/eokm/test.php b/ext/eokm/test.php
index 6c3d1ff7..dd44fba8 100644
--- a/ext/eokm/test.php
+++ b/ext/eokm/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class EokmTest extends ShimmiePHPUnitTestCase
 {
-    public function testPass()
+    public function testPass(): void
     {
         // no EOKM login details set, so be a no-op
         $this->log_in_as_user();
diff --git a/ext/et/test.php b/ext/et/test.php
index 8e94f525..d5ce1a75 100644
--- a/ext/et/test.php
+++ b/ext/et/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ETTest extends ShimmiePHPUnitTestCase
 {
-    public function testET()
+    public function testET(): void
     {
         $this->log_in_as_admin();
         $this->get_page("system_info");
diff --git a/ext/et_server/test.php b/ext/et_server/test.php
index 9b80e637..6d643d56 100644
--- a/ext/et_server/test.php
+++ b/ext/et_server/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ETServerTest extends ShimmiePHPUnitTestCase
 {
-    public function testView()
+    public function testView(): void
     {
         $this->post_page("register.php", ["data" => "test entry"]);
 
diff --git a/ext/ext_manager/test.php b/ext/ext_manager/test.php
index acb56b77..e1da9dc5 100644
--- a/ext/ext_manager/test.php
+++ b/ext/ext_manager/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ExtManagerTest extends ShimmiePHPUnitTestCase
 {
-    public function testAuth()
+    public function testAuth(): void
     {
         $this->get_page('ext_manager');
         $this->assert_title("Extensions");
diff --git a/ext/favorites/test.php b/ext/favorites/test.php
index ed1247bc..aa24efcc 100644
--- a/ext/favorites/test.php
+++ b/ext/favorites/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class FavoritesTest extends ShimmiePHPUnitTestCase
 {
-    public function testFavorites()
+    public function testFavorites(): void
     {
         global $user;
         $this->log_in_as_user();
diff --git a/ext/featured/test.php b/ext/featured/test.php
index ef0c4119..c0c82eb3 100644
--- a/ext/featured/test.php
+++ b/ext/featured/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class FeaturedTest extends ShimmiePHPUnitTestCase
 {
-    public function testFeatured()
+    public function testFeatured(): void
     {
         global $config;
 
diff --git a/ext/four_oh_four/test.php b/ext/four_oh_four/test.php
index 5c71a839..2e0c0efe 100644
--- a/ext/four_oh_four/test.php
+++ b/ext/four_oh_four/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class FourOhFourTest extends ShimmiePHPUnitTestCase
 {
-    public function test404Handler()
+    public function test404Handler(): void
     {
         $this->get_page('not/a/page');
         // most descriptive error first
diff --git a/ext/graphql/test.php b/ext/graphql/test.php
index db30ca7f..98146745 100644
--- a/ext/graphql/test.php
+++ b/ext/graphql/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class GraphQLTest extends ShimmiePHPUnitTestCase
 {
-    public function testSchema()
+    public function testSchema(): void
     {
         $schema = GraphQL::get_schema();
         $schema->assertValid();
diff --git a/ext/handle_archive/test.php b/ext/handle_archive/test.php
index bea2c0e0..a4582ffa 100644
--- a/ext/handle_archive/test.php
+++ b/ext/handle_archive/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ArchiveFileHandlerTest extends ShimmiePHPUnitTestCase
 {
-    public function testArchiveHander()
+    public function testArchiveHander(): void
     {
         $this->log_in_as_user();
         system("zip -q tests/test.zip tests/pbx_screenshot.jpg tests/favicon.png");
diff --git a/ext/handle_ico/test.php b/ext/handle_ico/test.php
index 9e108112..2a1db252 100644
--- a/ext/handle_ico/test.php
+++ b/ext/handle_ico/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class IcoFileHandlerTest extends ShimmiePHPUnitTestCase
 {
-    public function testIcoHander()
+    public function testIcoHander(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("ext/static_files/static/favicon.ico", "shimmie favicon");
diff --git a/ext/handle_pixel/test.php b/ext/handle_pixel/test.php
index 0b12a459..c83f06d6 100644
--- a/ext/handle_pixel/test.php
+++ b/ext/handle_pixel/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class PixelFileHandlerTest extends ShimmiePHPUnitTestCase
 {
-    public function testPixelHander()
+    public function testPixelHander(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
diff --git a/ext/handle_svg/test.php b/ext/handle_svg/test.php
index 60652ffe..958f4cf1 100644
--- a/ext/handle_svg/test.php
+++ b/ext/handle_svg/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class SVGFileHandlerTest extends ShimmiePHPUnitTestCase
 {
-    public function testSVGHander()
+    public function testSVGHander(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/test.svg", "something");
@@ -18,7 +18,7 @@ class SVGFileHandlerTest extends ShimmiePHPUnitTestCase
         # FIXME: test that it gets displayed properly
     }
 
-    public function testAbusiveSVG()
+    public function testAbusiveSVG(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/alert.svg", "something");
diff --git a/ext/help_pages/test.php b/ext/help_pages/test.php
index 80a5de59..151f7455 100644
--- a/ext/help_pages/test.php
+++ b/ext/help_pages/test.php
@@ -6,13 +6,13 @@ namespace Shimmie2;
 
 class HelpPagesTest extends ShimmiePHPUnitTestCase
 {
-    public function test_list()
+    public function test_list(): void
     {
         send_event(new HelpPageListBuildingEvent());
         $this->assertTrue(true);
     }
 
-    public function test_page()
+    public function test_page(): void
     {
         send_event(new HelpPageBuildingEvent("test"));
         $this->assertTrue(true);
diff --git a/ext/home/test.php b/ext/home/test.php
index 3dece097..b4813cda 100644
--- a/ext/home/test.php
+++ b/ext/home/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class HomeTest extends ShimmiePHPUnitTestCase
 {
-    public function testHomePage()
+    public function testHomePage(): void
     {
         $page = $this->get_page('home');
         $this->assertStringContainsString("Posts", $page->data);
diff --git a/ext/image/test.php b/ext/image/test.php
index 3b5821ab..d2eef83c 100644
--- a/ext/image/test.php
+++ b/ext/image/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ImageIOTest extends ShimmiePHPUnitTestCase
 {
-    public function testUserStats()
+    public function testUserStats(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "test");
@@ -26,7 +26,7 @@ class ImageIOTest extends ShimmiePHPUnitTestCase
         $this->assertEquals(200, $page->code);
     }
 
-    public function testDeleteRequest()
+    public function testDeleteRequest(): void
     {
         $this->log_in_as_admin();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "test");
diff --git a/ext/image_hash_ban/test.php b/ext/image_hash_ban/test.php
index a5d6ff22..9ad35fde 100644
--- a/ext/image_hash_ban/test.php
+++ b/ext/image_hash_ban/test.php
@@ -8,14 +8,14 @@ class ImageBanTest extends ShimmiePHPUnitTestCase
 {
     private string $hash = "feb01bab5698a11dd87416724c7a89e3";
 
-    public function testPages()
+    public function testPages(): void
     {
         $this->log_in_as_admin();
         $page = $this->get_page("image_hash_ban/list");
         $this->assertEquals(200, $page->code);
     }
 
-    public function testBan()
+    public function testBan(): void
     {
         $this->log_in_as_admin();
 
diff --git a/ext/image_view_counter/test.php b/ext/image_view_counter/test.php
index fc6e1c84..61cf0100 100644
--- a/ext/image_view_counter/test.php
+++ b/ext/image_view_counter/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ImageViewCounterTest extends ShimmiePHPUnitTestCase
 {
-    public function testPostView()
+    public function testPostView(): void
     {
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
         $this->log_in_as_admin();
@@ -14,7 +14,7 @@ class ImageViewCounterTest extends ShimmiePHPUnitTestCase
         $this->assert_text("Views");
     }
 
-    public function testPopular()
+    public function testPopular(): void
     {
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
         $this->get_page("post/view/$image_id");
diff --git a/ext/index/test.php b/ext/index/test.php
index ab6d16f9..f5542a2a 100644
--- a/ext/index/test.php
+++ b/ext/index/test.php
@@ -8,7 +8,7 @@ use PHPUnit\Framework\Attributes\Depends;
 
 class IndexTest extends ShimmiePHPUnitTestCase
 {
-    public function testIndexPage()
+    public function testIndexPage(): void
     {
         $this->get_page('post/list');
         $this->assert_title("Welcome to Shimmie");
@@ -51,7 +51,7 @@ class IndexTest extends ShimmiePHPUnitTestCase
 
     // This isn't really an index thing, we just want to test this from
     // SOMEWHERE because the default theme doesn't use them.
-    public function test_nav()
+    public function test_nav(): void
     {
         send_event(new UserLoginEvent(User::by_name(self::$user_name)));
         send_event(new PageNavBuildingEvent());
diff --git a/ext/ipban/test.php b/ext/ipban/test.php
index 6beb6ede..4be3e31d 100644
--- a/ext/ipban/test.php
+++ b/ext/ipban/test.php
@@ -8,14 +8,14 @@ class IPBanTest extends ShimmiePHPUnitTestCase
 {
     # FIXME: test that the IP is actually banned
 
-    public function testAccess()
+    public function testAccess(): void
     {
         $page = $this->get_page('ip_ban/list');
         $this->assertEquals(403, $page->code);
         $this->assertEquals("Permission Denied", $page->title);
     }
 
-    public function testIPBan()
+    public function testIPBan(): void
     {
         global $database;
 
@@ -52,7 +52,7 @@ class IPBanTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function test_all()
+    public function test_all(): void
     {
         // just test it doesn't crash for now
         $this->log_in_as_admin();
diff --git a/ext/link_image/test.php b/ext/link_image/test.php
index 5681bf12..cf4df5ae 100644
--- a/ext/link_image/test.php
+++ b/ext/link_image/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class LinkImageTest extends ShimmiePHPUnitTestCase
 {
-    public function testLinkImage()
+    public function testLinkImage(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pie");
diff --git a/ext/log_db/test.php b/ext/log_db/test.php
index 9dac1ed0..2aa05ff7 100644
--- a/ext/log_db/test.php
+++ b/ext/log_db/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class LogDatabaseTest extends ShimmiePHPUnitTestCase
 {
-    public function testLog()
+    public function testLog(): void
     {
         $this->log_in_as_admin();
         $this->get_page("log/view");
diff --git a/ext/mime/test.php b/ext/mime/test.php
index 1c374a32..788e55f5 100644
--- a/ext/mime/test.php
+++ b/ext/mime/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class MimeSystemTest extends ShimmiePHPUnitTestCase
 {
-    public function testJPEG()
+    public function testJPEG(): void
     {
         $result = MimeType::get_for_file("tests/bedroom_workshop.jpg");
         $this->assertEquals(MimeType::JPEG, $result);
diff --git a/ext/not_a_tag/test.php b/ext/not_a_tag/test.php
index 98202af7..87e40560 100644
--- a/ext/not_a_tag/test.php
+++ b/ext/not_a_tag/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class NotATagTest extends ShimmiePHPUnitTestCase
 {
-    public function testUntags()
+    public function testUntags(): void
     {
         global $database;
         $database->execute("DELETE FROM untags");
diff --git a/ext/numeric_score/test.php b/ext/numeric_score/test.php
index 44662acc..ab8819ed 100644
--- a/ext/numeric_score/test.php
+++ b/ext/numeric_score/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class NumericScoreTest extends ShimmiePHPUnitTestCase
 {
-    public function testNumericScore()
+    public function testNumericScore(): void
     {
         global $user;
 
diff --git a/ext/pm/test.php b/ext/pm/test.php
index 7ad5595d..a0a7069b 100644
--- a/ext/pm/test.php
+++ b/ext/pm/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class PrivMsgTest extends ShimmiePHPUnitTestCase
 {
-    public function testUserReadOwnMessage()
+    public function testUserReadOwnMessage(): void
     {
         // Send from admin to user
         $this->log_in_as_admin();
@@ -37,7 +37,7 @@ class PrivMsgTest extends ShimmiePHPUnitTestCase
         // $this->assert_text("No such PM");
     }
 
-    public function testAdminReadOtherMessage()
+    public function testAdminReadOtherMessage(): void
     {
         // Send from admin to user
         $this->log_in_as_admin();
diff --git a/ext/pools/test.php b/ext/pools/test.php
index a10f4cab..b368a6ac 100644
--- a/ext/pools/test.php
+++ b/ext/pools/test.php
@@ -20,7 +20,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
         }
     }
 
-    public function testAnon()
+    public function testAnon(): void
     {
         $this->log_out();
 
@@ -53,7 +53,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testOnViewImage($args)
+    public function testOnViewImage($args): void
     {
         [$pool_id, $image_ids] = $this->testCreate();
 
@@ -67,7 +67,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testSearch($args)
+    public function testSearch($args): void
     {
         [$pool_id, $image_ids] = $this->testCreate();
 
@@ -79,7 +79,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testList($args)
+    public function testList($args): void
     {
         $this->testCreate();
         $this->get_page("pool/list");
@@ -87,7 +87,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testView($args)
+    public function testView($args): void
     {
         [$pool_id, $image_ids] = $this->testCreate();
 
@@ -96,7 +96,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testHistory($args)
+    public function testHistory($args): void
     {
         [$pool_id, $image_ids] = $this->testCreate();
 
@@ -105,7 +105,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testCreate')]
-    public function testImport($args)
+    public function testImport($args): void
     {
         [$pool_id, $image_ids] = $this->testCreate();
 
@@ -131,7 +131,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testRemovePosts')]
-    public function testAddPosts($args)
+    public function testAddPosts($args): void
     {
         [$pool_id, $image_ids] = $this->testRemovePosts(null);
 
@@ -156,7 +156,7 @@ class PoolsTest extends ShimmiePHPUnitTestCase
         return [$pool_id, $image_ids];
     }
 
-    public function testNuke()
+    public function testNuke(): void
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "pbx");
diff --git a/ext/random_image/test.php b/ext/random_image/test.php
index d39391e6..44a00077 100644
--- a/ext/random_image/test.php
+++ b/ext/random_image/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class RandomImageTest extends ShimmiePHPUnitTestCase
 {
-    public function testRandom()
+    public function testRandom(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "test");
@@ -23,7 +23,7 @@ class RandomImageTest extends ShimmiePHPUnitTestCase
         # FIXME: assert($raw == file(blah.jpg))
     }
 
-    public function testPostListBlock()
+    public function testPostListBlock(): void
     {
         global $config;
 
diff --git a/ext/rating/test.php b/ext/rating/test.php
index 9f5ff724..7d4f744d 100644
--- a/ext/rating/test.php
+++ b/ext/rating/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class RatingsTest extends ShimmiePHPUnitTestCase
 {
-    public function testRatingSafe()
+    public function testRatingSafe(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx");
@@ -25,7 +25,7 @@ class RatingsTest extends ShimmiePHPUnitTestCase
         $this->assert_search_results(["rating=q"], []);
     }
 
-    public function testRatingExplicit()
+    public function testRatingExplicit(): void
     {
         global $config;
         $config->set_array("ext_rating_anonymous_privs", ["s", "q"]);
@@ -39,7 +39,7 @@ class RatingsTest extends ShimmiePHPUnitTestCase
         $this->assert_search_results(["pbx"], []);
     }
 
-    public function testUserConfig()
+    public function testUserConfig(): void
     {
         global $config, $user_config;
 
diff --git a/ext/regen_thumb/test.php b/ext/regen_thumb/test.php
index 0e84b818..2eef060c 100644
--- a/ext/regen_thumb/test.php
+++ b/ext/regen_thumb/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class RegenThumbTest extends ShimmiePHPUnitTestCase
 {
-    public function testRegenThumb()
+    public function testRegenThumb(): void
     {
         $this->log_in_as_admin();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
diff --git a/ext/relationships/test.php b/ext/relationships/test.php
index 61bd8336..6e310817 100644
--- a/ext/relationships/test.php
+++ b/ext/relationships/test.php
@@ -78,7 +78,7 @@ class RelationshipsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testSetParent')]
-    public function testSearch($imgs)
+    public function testSearch($imgs): void
     {
         [$image_1, $image_2, $image_3] = $this->testSetParent(null);
 
@@ -91,7 +91,7 @@ class RelationshipsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testChangeParent')]
-    public function testRemoveParent($imgs)
+    public function testRemoveParent($imgs): void
     {
         [$image_1, $image_2, $image_3] = $this->testChangeParent(null);
 
@@ -187,7 +187,7 @@ class RelationshipsTest extends ShimmiePHPUnitTestCase
     }
 
     #[Depends('testSetChildByTag')]
-    public function testRemoveParentByTag($imgs)
+    public function testRemoveParentByTag($imgs): void
     {
         [$image_1, $image_2, $image_3] = $this->testSetChildByTag(null);
         assert(!is_null($image_3));
diff --git a/ext/replace_file/test.php b/ext/replace_file/test.php
index 2b537dce..adadbabf 100644
--- a/ext/replace_file/test.php
+++ b/ext/replace_file/test.php
@@ -6,14 +6,14 @@ namespace Shimmie2;
 
 class ReplaceFileTest extends ShimmiePHPUnitTestCase
 {
-    public function testReplacePage()
+    public function testReplacePage(): void
     {
         $this->log_in_as_admin();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
         $this->get_page("replace/$image_id");
         $this->assert_title("Replace File");
     }
-    public function testReplace()
+    public function testReplace(): void
     {
         global $database;
         $this->log_in_as_admin();
diff --git a/ext/report_image/test.php b/ext/report_image/test.php
index 57996eaf..4d3f7d03 100644
--- a/ext/report_image/test.php
+++ b/ext/report_image/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ReportImageTest extends ShimmiePHPUnitTestCase
 {
-    public function testReportImage()
+    public function testReportImage(): void
     {
         global $config, $database, $user;
 
diff --git a/ext/res_limit/test.php b/ext/res_limit/test.php
index d8a51de4..618a15ff 100644
--- a/ext/res_limit/test.php
+++ b/ext/res_limit/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class ResolutionLimitTest extends ShimmiePHPUnitTestCase
 {
-    public function testResLimitOK()
+    public function testResLimitOK(): void
     {
         global $config;
         $config->set_int("upload_min_height", 0);
@@ -23,7 +23,7 @@ class ResolutionLimitTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("ratio");
     }
 
-    public function testResLimitSmall()
+    public function testResLimitSmall(): void
     {
         global $config;
         $config->set_int("upload_min_height", 900);
@@ -39,7 +39,7 @@ class ResolutionLimitTest extends ShimmiePHPUnitTestCase
         $this->assertEquals("Post too small", $e->getMessage());
     }
 
-    public function testResLimitLarge()
+    public function testResLimitLarge(): void
     {
         global $config;
         $config->set_int("upload_min_height", 0);
@@ -54,7 +54,7 @@ class ResolutionLimitTest extends ShimmiePHPUnitTestCase
         $this->assertEquals("Post too large", $e->getMessage());
     }
 
-    public function testResLimitRatio()
+    public function testResLimitRatio(): void
     {
         global $config;
         $config->set_int("upload_min_height", -1);
diff --git a/ext/rss_comments/test.php b/ext/rss_comments/test.php
index c3ce163e..868f143c 100644
--- a/ext/rss_comments/test.php
+++ b/ext/rss_comments/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class RSSCommentsTest extends ShimmiePHPUnitTestCase
 {
-    public function testImageFeed()
+    public function testImageFeed(): void
     {
         global $user;
         $this->log_in_as_user();
diff --git a/ext/rss_images/test.php b/ext/rss_images/test.php
index 89dc8acc..e23c40a4 100644
--- a/ext/rss_images/test.php
+++ b/ext/rss_images/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class RSSImagesTest extends ShimmiePHPUnitTestCase
 {
-    public function testImageFeed()
+    public function testImageFeed(): void
     {
         $this->log_in_as_user();
         $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
diff --git a/ext/setup/test.php b/ext/setup/test.php
index e7eb169d..f732efb7 100644
--- a/ext/setup/test.php
+++ b/ext/setup/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class SetupTest extends ShimmiePHPUnitTestCase
 {
-    public function testNiceUrlsTest()
+    public function testNiceUrlsTest(): void
     {
         # XXX: this only checks that the text is "ok", to check
         # for a bug where it was coming out as "\nok"; it doesn't
@@ -16,14 +16,14 @@ class SetupTest extends ShimmiePHPUnitTestCase
         $this->assert_no_content("\n");
     }
 
-    public function testAuthAnon()
+    public function testAuthAnon(): void
     {
         $this->get_page('setup');
         $this->assert_response(403);
         $this->assert_title("Permission Denied");
     }
 
-    public function testAuthUser()
+    public function testAuthUser(): void
     {
         $this->log_in_as_user();
         $this->get_page('setup');
@@ -31,7 +31,7 @@ class SetupTest extends ShimmiePHPUnitTestCase
         $this->assert_title("Permission Denied");
     }
 
-    public function testAuthAdmin()
+    public function testAuthAdmin(): void
     {
         $this->log_in_as_admin();
         $this->get_page('setup');
@@ -39,7 +39,7 @@ class SetupTest extends ShimmiePHPUnitTestCase
         $this->assert_text("General");
     }
 
-    public function testAdvanced()
+    public function testAdvanced(): void
     {
         $this->log_in_as_admin();
         $this->get_page('setup/advanced');
diff --git a/ext/site_description/test.php b/ext/site_description/test.php
index 8d07917f..b2af0dbf 100644
--- a/ext/site_description/test.php
+++ b/ext/site_description/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class SiteDescriptionTest extends ShimmiePHPUnitTestCase
 {
-    public function testSiteDescription()
+    public function testSiteDescription(): void
     {
         global $config, $page;
         $config->set_string("site_description", "A Shimmie testbed");
@@ -17,7 +17,7 @@ class SiteDescriptionTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testSiteKeywords()
+    public function testSiteKeywords(): void
     {
         global $config, $page;
         $config->set_string("site_keywords", "foo,bar,baz");
diff --git a/ext/sitemap/test.php b/ext/sitemap/test.php
index b36e5a9c..ad5c0e03 100644
--- a/ext/sitemap/test.php
+++ b/ext/sitemap/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class XMLSitemapTest extends ShimmiePHPUnitTestCase
 {
-    public function testBasic()
+    public function testBasic(): void
     {
         $page = $this->get_page('sitemap.xml');
         $this->assertEquals(200, $page->code);
diff --git a/ext/static_files/test.php b/ext/static_files/test.php
index e26288b9..2255b0e0 100644
--- a/ext/static_files/test.php
+++ b/ext/static_files/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class StaticFilesTest extends ShimmiePHPUnitTestCase
 {
-    public function testStaticHandler()
+    public function testStaticHandler(): void
     {
         $this->get_page('favicon.ico');
         $this->assert_response(200);
diff --git a/ext/system/test.php b/ext/system/test.php
index 170d3b08..3b259679 100644
--- a/ext/system/test.php
+++ b/ext/system/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class SystemTest extends ShimmiePHPUnitTestCase
 {
-    public function testView()
+    public function testView(): void
     {
         global $page;
         $this->get_page("system");
diff --git a/ext/tag_edit/test.php b/ext/tag_edit/test.php
index cd0f97a3..8a1034dd 100644
--- a/ext/tag_edit/test.php
+++ b/ext/tag_edit/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class TagEditTest extends ShimmiePHPUnitTestCase
 {
-    public function testValidChange()
+    public function testValidChange(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx");
@@ -22,7 +22,7 @@ class TagEditTest extends ShimmiePHPUnitTestCase
         $this->assert_title("Post $image_id: new");
     }
 
-    public function testInvalidChange()
+    public function testInvalidChange(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx");
@@ -39,7 +39,7 @@ class TagEditTest extends ShimmiePHPUnitTestCase
         $this->assertEquals("Can't set a tag which contains a wildcard (*)", $e->getMessage());
     }
 
-    public function testTagEdit_tooLong()
+    public function testTagEdit_tooLong(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", str_repeat("a", 500));
@@ -47,7 +47,7 @@ class TagEditTest extends ShimmiePHPUnitTestCase
         $this->assert_title("Post $image_id: tagme");
     }
 
-    public function testSourceEdit()
+    public function testSourceEdit(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx");
diff --git a/ext/tag_history/test.php b/ext/tag_history/test.php
index e94f2900..4c3fc084 100644
--- a/ext/tag_history/test.php
+++ b/ext/tag_history/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class TagHistoryTest extends ShimmiePHPUnitTestCase
 {
-    public function testTagHistory()
+    public function testTagHistory(): void
     {
         $this->log_in_as_admin();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "old_tag");
diff --git a/ext/tag_list/test.php b/ext/tag_list/test.php
index 1f04f98a..8d27af0a 100644
--- a/ext/tag_list/test.php
+++ b/ext/tag_list/test.php
@@ -8,7 +8,7 @@ class TagListTest extends ShimmiePHPUnitTestCase
 {
     private array $pages = ["map", "alphabetic", "popularity", "categories"];
 
-    public function testTagList()
+    public function testTagList(): void
     {
         $this->get_page('tags/map');
         $this->assert_title('Tag List');
@@ -25,7 +25,7 @@ class TagListTest extends ShimmiePHPUnitTestCase
         # FIXME: test that these show the right stuff
     }
 
-    public function testMinCount()
+    public function testMinCount(): void
     {
         foreach ($this->pages as $page) {
             $this->get_page("tags/$page", ["mincount" => 999999]);
diff --git a/ext/tag_tools/test.php b/ext/tag_tools/test.php
index 8d7cc505..41e88715 100644
--- a/ext/tag_tools/test.php
+++ b/ext/tag_tools/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class TagToolsTest extends ShimmiePHPUnitTestCase
 {
-    public function testLowercaseAndSetCase()
+    public function testLowercaseAndSetCase(): void
     {
         // Create a problem
         $ts = time(); // we need a tag that hasn't been used before
@@ -34,7 +34,7 @@ class TagToolsTest extends ShimmiePHPUnitTestCase
     }
 
     # FIXME: make sure the admin tools actually work
-    public function testRecount()
+    public function testRecount(): void
     {
         global $database;
 
diff --git a/ext/tips/test.php b/ext/tips/test.php
index 4a3d22dc..737da52f 100644
--- a/ext/tips/test.php
+++ b/ext/tips/test.php
@@ -14,7 +14,7 @@ class TipsTest extends ShimmiePHPUnitTestCase
         $database->execute("DELETE FROM tips");
     }
 
-    public function testImageless()
+    public function testImageless(): void
     {
         global $database;
         $this->log_in_as_admin();
@@ -32,7 +32,7 @@ class TipsTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("a postless tip");
     }
 
-    public function testImaged()
+    public function testImaged(): void
     {
         global $database;
         $this->log_in_as_admin();
@@ -50,7 +50,7 @@ class TipsTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("a postless tip");
     }
 
-    public function testDisabled()
+    public function testDisabled(): void
     {
         global $database;
         $this->log_in_as_admin();
diff --git a/ext/upload/test.php b/ext/upload/test.php
index 85ab424c..bdfb650b 100644
--- a/ext/upload/test.php
+++ b/ext/upload/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class UploadTest extends ShimmiePHPUnitTestCase
 {
-    public function testUploadPage()
+    public function testUploadPage(): void
     {
         $this->log_in_as_user();
 
@@ -15,7 +15,7 @@ class UploadTest extends ShimmiePHPUnitTestCase
     }
 
     // Because $this->post_image() sends the event directly
-    public function testRawUpload()
+    public function testRawUpload(): void
     {
         global $database;
 
@@ -50,7 +50,7 @@ class UploadTest extends ShimmiePHPUnitTestCase
         $this->assertEquals(4, $database->get_one("SELECT COUNT(*) FROM images"));
     }
 
-    public function testUpload()
+    public function testUpload(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
@@ -60,7 +60,7 @@ class UploadTest extends ShimmiePHPUnitTestCase
         $this->assert_title("Post $image_id: computer pbx screenshot");
     }
 
-    public function testRejectDupe()
+    public function testRejectDupe(): void
     {
         $this->post_image("tests/pbx_screenshot.jpg", "pbx computer screenshot");
 
@@ -70,13 +70,13 @@ class UploadTest extends ShimmiePHPUnitTestCase
         $this->assertStringContainsString("already has hash", $e->getMessage());
     }
 
-    public function testRejectUnknownFiletype()
+    public function testRejectUnknownFiletype(): void
     {
         $this->expectException(\Exception::class);
         $this->post_image("index.php", "test");
     }
 
-    public function testRejectHuge()
+    public function testRejectHuge(): void
     {
         // FIXME: huge.dat is rejected for other reasons; manual testing shows that this works
         file_put_contents("data/huge.jpg", file_get_contents("tests/pbx_screenshot.jpg") . str_repeat("U", 1024 * 1024 * 3));
diff --git a/ext/user/test.php b/ext/user/test.php
index 0761ecc8..2aa53d8e 100644
--- a/ext/user/test.php
+++ b/ext/user/test.php
@@ -6,7 +6,7 @@ namespace Shimmie2;
 
 class UserPageTest extends ShimmiePHPUnitTestCase
 {
-    public function testUserPage()
+    public function testUserPage(): void
     {
         $this->get_page('user');
         $this->assert_title("Not Logged In");
@@ -42,19 +42,19 @@ class UserPageTest extends ShimmiePHPUnitTestCase
     # FIXME: test user creation
     # FIXME: test adminifying
     # FIXME: test password reset
-    public function testUserList()
+    public function testUserList(): void
     {
         $this->get_page('user_admin/list');
         $this->assert_text("demo");
     }
 
-    public function testUserClasses()
+    public function testUserClasses(): void
     {
         $this->get_page('user_admin/classes');
         $this->assert_text("admin");
     }
 
-    public function testCreateOther()
+    public function testCreateOther(): void
     {
         global $page;
 
diff --git a/ext/user_config/test.php b/ext/user_config/test.php
index 5e12abbc..29d984e3 100644
--- a/ext/user_config/test.php
+++ b/ext/user_config/test.php
@@ -8,7 +8,7 @@ class UserConfigTest extends ShimmiePHPUnitTestCase
 {
     private const OPTIONS_BLOCK_TITLE = "User Options";
 
-    public function testUserConfigPage()
+    public function testUserConfigPage(): void
     {
         $this->get_page('user_config');
         $this->assert_title("Permission Denied");
diff --git a/ext/view/test.php b/ext/view/test.php
index 37bdd2dc..cbb1e3c0 100644
--- a/ext/view/test.php
+++ b/ext/view/test.php
@@ -12,7 +12,7 @@ class ViewPostTest extends ShimmiePHPUnitTestCase
         // FIXME: upload images
     }
 
-    public function testViewPage()
+    public function testViewPage(): void
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "test");
@@ -21,7 +21,7 @@ class ViewPostTest extends ShimmiePHPUnitTestCase
         $this->assert_title("Post $image_id_1: test");
     }
 
-    public function testViewInfo()
+    public function testViewInfo(): void
     {
         global $config;
 
@@ -33,7 +33,7 @@ class ViewPostTest extends ShimmiePHPUnitTestCase
         $this->assert_text("640x480 // 19KB // jpg");
     }
 
-    public function testPrevNext()
+    public function testPrevNext(): void
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/pbx_screenshot.jpg", "test");
@@ -66,7 +66,7 @@ class ViewPostTest extends ShimmiePHPUnitTestCase
         $this->assertEquals(404, $page->code);
     }
 
-    public function testPrevNextDisabledWhenOrdered()
+    public function testPrevNextDisabledWhenOrdered(): void
     {
         $this->log_in_as_user();
         $image_id = $this->post_image("tests/pbx_screenshot.jpg", "test");
@@ -84,7 +84,7 @@ class ViewPostTest extends ShimmiePHPUnitTestCase
         $this->assert_no_text("Prev");
     }
 
-    public function testView404()
+    public function testView404(): void
     {
         $this->log_in_as_user();
         $image_id_1 = $this->post_image("tests/favicon.png", "test");
diff --git a/ext/wiki/test.php b/ext/wiki/test.php
index 52da9b00..86ef0f61 100644
--- a/ext/wiki/test.php
+++ b/ext/wiki/test.php
@@ -6,14 +6,14 @@ namespace Shimmie2;
 
 class WikiTest extends ShimmiePHPUnitTestCase
 {
-    public function testIndex()
+    public function testIndex(): void
     {
         $this->get_page("wiki");
         $this->assert_title("Index");
         $this->assert_text("This is a default page");
     }
 
-    public function testAccess()
+    public function testAccess(): void
     {
         global $config;
         foreach (["anon", "user", "admin"] as $user) {
@@ -53,7 +53,7 @@ class WikiTest extends ShimmiePHPUnitTestCase
         }
     }
 
-    public function testDefault()
+    public function testDefault(): void
     {
         global $user;
         $this->log_in_as_admin();
@@ -82,7 +82,7 @@ class WikiTest extends ShimmiePHPUnitTestCase
         $this->assert_text("This is a default page");
     }
 
-    public function testRevisions()
+    public function testRevisions(): void
     {
         global $user;
         $this->log_in_as_admin();
diff --git a/ext/word_filter/test.php b/ext/word_filter/test.php
index a5ba62c2..6786b192 100644
--- a/ext/word_filter/test.php
+++ b/ext/word_filter/test.php
@@ -23,7 +23,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         $this->assert_text($out);
     }
 
-    public function testRegular()
+    public function testRegular(): void
     {
         $this->_doThings(
             "posted by a whore",
@@ -31,7 +31,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testReplaceAll()
+    public function testReplaceAll(): void
     {
         $this->_doThings(
             "a whore is a whore is a whore",
@@ -39,7 +39,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testMixedCase()
+    public function testMixedCase(): void
     {
         $this->_doThings(
             "monkey WhorE",
@@ -47,7 +47,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testOnlyWholeWords()
+    public function testOnlyWholeWords(): void
     {
         $this->_doThings(
             "my name is whoretta",
@@ -55,7 +55,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testMultipleWords()
+    public function testMultipleWords(): void
     {
         $this->_doThings(
             "I would like a duck",
@@ -63,7 +63,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testWhitespace()
+    public function testWhitespace(): void
     {
         $this->_doThings(
             "A colour is white",
@@ -71,7 +71,7 @@ class WordFilterTest extends ShimmiePHPUnitTestCase
         );
     }
 
-    public function testIgnoreInvalid()
+    public function testIgnoreInvalid(): void
     {
         $this->_doThings(
             "The word was invalid",