diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 8142b62ef4c0f..4ca1614154b6c 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -117,7 +117,10 @@ jobs:
           tool: cargo-insta
       - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
-        run: cargo insta test --all --all-features --unreferenced reject
+        run: cargo insta test --all --exclude ruff_dev --all-features --unreferenced reject
+      - name: "Run dev tests"
+        # e.g. generating the schema — these should not run with all features enabled
+        run: cargo insta test -p ruff_dev --unreferenced reject
       # Check for broken links in the documentation.
       - run: cargo doc --all --no-deps
         env:
@@ -146,7 +149,7 @@ jobs:
       - name: "Run tests"
         shell: bash
         # We can't reject unreferenced snapshots on windows because flake8_executable can't run on windows
-        run: cargo insta test --all --all-features
+        run: cargo insta test --all --exclude ruff_dev --all-features
 
   cargo-test-wasm:
     name: "cargo test (wasm)"
diff --git a/crates/ruff/Cargo.toml b/crates/ruff/Cargo.toml
index 71d1dce4097ff..0f54993d28da9 100644
--- a/crates/ruff/Cargo.toml
+++ b/crates/ruff/Cargo.toml
@@ -54,6 +54,8 @@ walkdir = { workspace = true }
 wild = { workspace = true }
 
 [dev-dependencies]
+# Enable test rules during development
+ruff_linter = { path = "../ruff_linter", features = ["clap", "test-rules"] }
 assert_cmd = { workspace = true }
 # Avoid writing colored snapshots when running tests from the terminal
 colored = { workspace = true, features = ["no-color"]}
diff --git a/crates/ruff/tests/integration_test.rs b/crates/ruff/tests/integration_test.rs
index 7aed76fee2df3..d21b44aa470f2 100644
--- a/crates/ruff/tests/integration_test.rs
+++ b/crates/ruff/tests/integration_test.rs
@@ -799,15 +799,18 @@ fn show_statistics() {
 
 #[test]
 fn nursery_prefix() {
-    // `--select E` should detect E741, but not E225, which is in the nursery.
-    let mut cmd = RuffCheck::default().args(["--select", "E"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    // Should only detect RUF90X, but not the unstable test rules
+    let mut cmd = RuffCheck::default().args(["--select", "RUF9"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
-    Found 1 error.
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
+    Found 4 errors.
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     "###);
@@ -815,16 +818,19 @@ fn nursery_prefix() {
 
 #[test]
 fn nursery_all() {
-    // `--select ALL` should detect E741, but not E225, which is in the nursery.
+    // Should detect RUF90X, but not the unstable test rules
     let mut cmd = RuffCheck::default().args(["--select", "ALL"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
     -:1:1: D100 Missing docstring in public module
-    Found 2 errors.
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
+    Found 5 errors.
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     warning: `one-blank-line-before-class` (D203) and `no-blank-line-before-class` (D211) are incompatible. Ignoring `one-blank-line-before-class`.
@@ -834,35 +840,32 @@ fn nursery_all() {
 
 #[test]
 fn nursery_direct() {
-    // `--select E225` should detect E225.
-    let mut cmd = RuffCheck::default().args(["--select", "E225"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    // Should warn that the nursery rule is selected without preview flag but still
+    // include the diagnostic
+    let mut cmd = RuffCheck::default().args(["--select", "RUF912"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:2: E225 [*] Missing whitespace around operator
+    -:1:1: RUF912 Hey this is a nursery test rule.
     Found 1 error.
-    [*] 1 fixable with the `--fix` option.
 
     ----- stderr -----
-    warning: Selection of nursery rule `E225` without the `--preview` flag is deprecated.
+    warning: Selection of nursery rule `RUF912` without the `--preview` flag is deprecated.
     "###);
 }
 
 #[test]
 fn nursery_group_selector() {
-    // Only nursery rules should be detected e.g. E225 and a warning should be displayed
+    // Only nursery rules should be detected e.g. RUF912
     let mut cmd = RuffCheck::default().args(["--select", "NURSERY"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
     -:1:1: CPY001 Missing copyright notice at top of file
-    -:1:2: E225 [*] Missing whitespace around operator
+    -:1:1: RUF912 Hey this is a nursery test rule.
     Found 2 errors.
-    [*] 1 fixable with the `--fix` option.
 
     ----- stderr -----
     warning: The `NURSERY` selector has been deprecated. Use the `--preview` flag instead.
@@ -871,12 +874,11 @@ fn nursery_group_selector() {
 
 #[test]
 fn nursery_group_selector_preview_enabled() {
-    // Only nursery rules should be detected e.g. E225 and a warning should be displayed
+    // A warning should be displayed due to deprecated selector usage
     let mut cmd = RuffCheck::default()
         .args(["--select", "NURSERY", "--preview"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 2
     ----- stdout -----
@@ -889,19 +891,22 @@ fn nursery_group_selector_preview_enabled() {
 
 #[test]
 fn preview_enabled_prefix() {
-    // E741 and E225 (preview) should both be detected
+    // All the RUF9XX test rules should be triggered
     let mut cmd = RuffCheck::default()
-        .args(["--select", "E", "--preview"])
+        .args(["--select", "RUF9", "--preview"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
-    -:1:2: E225 [*] Missing whitespace around operator
-    Found 2 errors.
-    [*] 1 fixable with the `--fix` option.
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
+    -:1:1: RUF911 Hey this is a preview test rule.
+    -:1:1: RUF912 Hey this is a nursery test rule.
+    Found 6 errors.
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     "###);
@@ -912,17 +917,20 @@ fn preview_enabled_all() {
     let mut cmd = RuffCheck::default()
         .args(["--select", "ALL", "--preview"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
     -:1:1: D100 Missing docstring in public module
     -:1:1: CPY001 Missing copyright notice at top of file
-    -:1:2: E225 [*] Missing whitespace around operator
-    Found 4 errors.
-    [*] 1 fixable with the `--fix` option.
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
+    -:1:1: RUF911 Hey this is a preview test rule.
+    -:1:1: RUF912 Hey this is a nursery test rule.
+    Found 8 errors.
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     warning: `one-blank-line-before-class` (D203) and `no-blank-line-before-class` (D211) are incompatible. Ignoring `one-blank-line-before-class`.
@@ -932,18 +940,16 @@ fn preview_enabled_all() {
 
 #[test]
 fn preview_enabled_direct() {
-    // E225 should be detected without warning
+    // Should be enabled without warning
     let mut cmd = RuffCheck::default()
-        .args(["--select", "E225", "--preview"])
+        .args(["--select", "RUF911", "--preview"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    assert_cmd_snapshot!(cmd, @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:2: E225 [*] Missing whitespace around operator
+    -:1:1: RUF911 Hey this is a preview test rule.
     Found 1 error.
-    [*] 1 fixable with the `--fix` option.
 
     ----- stderr -----
     "###);
@@ -951,45 +957,40 @@ fn preview_enabled_direct() {
 
 #[test]
 fn preview_disabled_direct() {
-    // FURB145 is preview not nursery so selecting should be empty
-    let mut cmd = RuffCheck::default().args(["--select", "FURB145"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("a = l[:]\n"), @r###"
+    // RUFF911 is preview not nursery so the selection should be empty
+    let mut cmd = RuffCheck::default().args(["--select", "RUF911"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
     success: true
     exit_code: 0
     ----- stdout -----
 
     ----- stderr -----
-    warning: Selection `FURB145` has no effect because the `--preview` flag was not included.
+    warning: Selection `RUF911` has no effect because the `--preview` flag was not included.
     "###);
 }
 
 #[test]
 fn preview_disabled_prefix_empty() {
-    // Warns that the selection is empty since all of the CPY rules are in preview
-    let mut cmd = RuffCheck::default().args(["--select", "CPY"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
+    // Warns that the selection is empty since all of the RUF91 rules are in preview
+    let mut cmd = RuffCheck::default().args(["--select", "RUF91"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
     success: true
     exit_code: 0
     ----- stdout -----
 
     ----- stderr -----
-    warning: Selection `CPY` has no effect because the `--preview` flag was not included.
+    warning: Selection `RUF91` has no effect because the `--preview` flag was not included.
     "###);
 }
 
 #[test]
 fn preview_disabled_does_not_warn_for_empty_ignore_selections() {
     // Does not warn that the selection is empty since the user is not trying to enable the rule
-    let mut cmd = RuffCheck::default().args(["--ignore", "CPY"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
-    success: false
-    exit_code: 1
+    let mut cmd = RuffCheck::default().args(["--ignore", "RUF9"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
+    success: true
+    exit_code: 0
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
-    Found 1 error.
 
     ----- stderr -----
     "###);
@@ -998,14 +999,11 @@ fn preview_disabled_does_not_warn_for_empty_ignore_selections() {
 #[test]
 fn preview_disabled_does_not_warn_for_empty_fixable_selections() {
     // Does not warn that the selection is empty since the user is not trying to enable the rule
-    let mut cmd = RuffCheck::default().args(["--fixable", "CPY"]).build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("I=42\n"), @r###"
-    success: false
-    exit_code: 1
+    let mut cmd = RuffCheck::default().args(["--fixable", "RUF9"]).build();
+    assert_cmd_snapshot!(cmd, @r###"
+    success: true
+    exit_code: 0
     ----- stdout -----
-    -:1:1: E741 Ambiguous variable name: `I`
-    Found 1 error.
 
     ----- stderr -----
     "###);
@@ -1032,20 +1030,25 @@ fn preview_group_selector() {
 
 #[test]
 fn preview_enabled_group_ignore() {
-    // `--select E --ignore PREVIEW` should detect E741 and E225, which is in preview but "E" is more specific.
+    // Should detect stable and unstable rules, RUF9 is more specific than RUF so ignore has no effect
     let mut cmd = RuffCheck::default()
-        .args(["--select", "E", "--ignore", "PREVIEW", "--preview"])
+        .args(["--select", "RUF9", "--ignore", "RUF", "--preview"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("I=42\n"), @r###"
     success: false
-    exit_code: 2
+    exit_code: 1
     ----- stdout -----
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
+    -:1:1: RUF911 Hey this is a preview test rule.
+    -:1:1: RUF912 Hey this is a nursery test rule.
+    Found 6 errors.
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
-    error: invalid value 'PREVIEW' for '--ignore <RULE_CODE>'
-
-    For more information, try '--help'.
     "###);
 }
 
@@ -1150,16 +1153,15 @@ fn check_input_from_argfile() -> Result<()> {
 #[test]
 fn check_hints_hidden_unsafe_fixes() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034"])
+        .args(["--select", "RUF901,RUF902"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
-    -:2:7: UP034 [*] Avoid extraneous parentheses
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
     [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
@@ -1169,14 +1171,14 @@ fn check_hints_hidden_unsafe_fixes() {
 
 #[test]
 fn check_hints_hidden_unsafe_fixes_with_no_safe_fixes() {
-    let mut cmd = RuffCheck::default().args(["--select", "F601"]).build();
+    let mut cmd = RuffCheck::default().args(["--select", "RUF902"]).build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("x = {'a': 1, 'a': 1}\n"),
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 1 error.
     No fixes available (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
@@ -1187,16 +1189,15 @@ fn check_hints_hidden_unsafe_fixes_with_no_safe_fixes() {
 #[test]
 fn check_no_hint_for_hidden_unsafe_fixes_when_disabled() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--no-unsafe-fixes"])
+        .args(["--select", "RUF901,RUF902", "--no-unsafe-fixes"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
-    -:2:7: UP034 [*] Avoid extraneous parentheses
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
     [*] 1 fixable with the --fix option.
 
@@ -1207,7 +1208,7 @@ fn check_no_hint_for_hidden_unsafe_fixes_when_disabled() {
 #[test]
 fn check_no_hint_for_hidden_unsafe_fixes_with_no_safe_fixes_when_disabled() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601", "--no-unsafe-fixes"])
+        .args(["--select", "RUF902", "--no-unsafe-fixes"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("x = {'a': 1, 'a': 1}\n"),
@@ -1215,7 +1216,7 @@ fn check_no_hint_for_hidden_unsafe_fixes_with_no_safe_fixes_when_disabled() {
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 1 error.
 
     ----- stderr -----
@@ -1225,16 +1226,15 @@ fn check_no_hint_for_hidden_unsafe_fixes_with_no_safe_fixes_when_disabled() {
 #[test]
 fn check_shows_unsafe_fixes_with_opt_in() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--unsafe-fixes"])
+        .args(["--select", "RUF901,RUF902", "--unsafe-fixes"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 [*] Dictionary key literal `'a'` repeated
-    -:2:7: UP034 [*] Avoid extraneous parentheses
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 [*] Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
     [*] 2 fixable with the --fix option.
 
@@ -1245,19 +1245,17 @@ fn check_shows_unsafe_fixes_with_opt_in() {
 #[test]
 fn fix_applies_safe_fixes_by_default() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--fix"])
+        .args(["--select", "RUF901,RUF902", "--fix"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    x = {'a': 1, 'a': 1}
-    print('foo')
+    # fix from stable-test-rule-safe-fix
 
     ----- stderr -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 2 errors (1 fixed, 1 remaining).
     No fixes available (1 hidden fix can be enabled with the `--unsafe-fixes` option).
     "###);
@@ -1266,16 +1264,15 @@ fn fix_applies_safe_fixes_by_default() {
 #[test]
 fn fix_applies_unsafe_fixes_with_opt_in() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--fix", "--unsafe-fixes"])
+        .args(["--select", "RUF901,RUF902", "--fix", "--unsafe-fixes"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: true
     exit_code: 0
     ----- stdout -----
-    x = {'a': 1}
-    print('foo')
+    # fix from stable-test-rule-unsafe-fix
+    # fix from stable-test-rule-safe-fix
 
     ----- stderr -----
     Found 2 errors (2 fixed, 0 remaining).
@@ -1285,7 +1282,7 @@ fn fix_applies_unsafe_fixes_with_opt_in() {
 #[test]
 fn fix_does_not_apply_display_only_fixes() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "B006", "--fix"])
+        .args(["--select", "RUF903", "--fix"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("def add_to_list(item, some_list=[]): ..."),
@@ -1295,7 +1292,7 @@ fn fix_does_not_apply_display_only_fixes() {
     ----- stdout -----
     def add_to_list(item, some_list=[]): ...
     ----- stderr -----
-    -:1:33: B006 Do not use mutable data structures for argument defaults
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
     Found 1 error.
     "###);
 }
@@ -1303,7 +1300,7 @@ fn fix_does_not_apply_display_only_fixes() {
 #[test]
 fn fix_does_not_apply_display_only_fixes_with_unsafe_fixes_enabled() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "B006", "--fix", "--unsafe-fixes"])
+        .args(["--select", "RUF903", "--fix", "--unsafe-fixes"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("def add_to_list(item, some_list=[]): ..."),
@@ -1313,7 +1310,7 @@ fn fix_does_not_apply_display_only_fixes_with_unsafe_fixes_enabled() {
     ----- stdout -----
     def add_to_list(item, some_list=[]): ...
     ----- stderr -----
-    -:1:33: B006 Do not use mutable data structures for argument defaults
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
     Found 1 error.
     "###);
 }
@@ -1321,19 +1318,16 @@ fn fix_does_not_apply_display_only_fixes_with_unsafe_fixes_enabled() {
 #[test]
 fn fix_only_unsafe_fixes_available() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601", "--fix"])
+        .args(["--select", "RUF902", "--fix"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    x = {'a': 1, 'a': 1}
-    print(('foo'))
 
     ----- stderr -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 1 error.
     No fixes available (1 hidden fix can be enabled with the `--unsafe-fixes` option).
     "###);
@@ -1342,16 +1336,14 @@ fn fix_only_unsafe_fixes_available() {
 #[test]
 fn fix_only_flag_applies_safe_fixes_by_default() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--fix-only"])
+        .args(["--select", "RUF901,RUF902", "--fix-only"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: true
     exit_code: 0
     ----- stdout -----
-    x = {'a': 1, 'a': 1}
-    print('foo')
+    # fix from stable-test-rule-safe-fix
 
     ----- stderr -----
     Fixed 1 error (1 additional fix available with `--unsafe-fixes`).
@@ -1361,16 +1353,15 @@ fn fix_only_flag_applies_safe_fixes_by_default() {
 #[test]
 fn fix_only_flag_applies_unsafe_fixes_with_opt_in() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--fix-only", "--unsafe-fixes"])
+        .args(["--select", "RUF901,RUF902", "--fix-only", "--unsafe-fixes"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: true
     exit_code: 0
     ----- stdout -----
-    x = {'a': 1}
-    print('foo')
+    # fix from stable-test-rule-unsafe-fix
+    # fix from stable-test-rule-safe-fix
 
     ----- stderr -----
     Fixed 2 errors.
@@ -1380,18 +1371,15 @@ fn fix_only_flag_applies_unsafe_fixes_with_opt_in() {
 #[test]
 fn diff_shows_safe_fixes_by_default() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--diff"])
+        .args(["--select", "RUF901,RUF902", "--diff"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    @@ -1,2 +1,2 @@
-     x = {'a': 1, 'a': 1}
-    -print(('foo'))
-    +print('foo')
+    @@ -0,0 +1 @@
+    +# fix from stable-test-rule-safe-fix
 
 
     ----- stderr -----
@@ -1403,19 +1391,16 @@ fn diff_shows_safe_fixes_by_default() {
 #[test]
 fn diff_shows_unsafe_fixes_with_opt_in() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601,UP034", "--diff", "--unsafe-fixes"])
+        .args(["--select", "RUF901,RUF902", "--diff", "--unsafe-fixes"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    @@ -1,2 +1,2 @@
-    -x = {'a': 1, 'a': 1}
-    -print(('foo'))
-    +x = {'a': 1}
-    +print('foo')
+    @@ -0,0 +1,2 @@
+    +# fix from stable-test-rule-unsafe-fix
+    +# fix from stable-test-rule-safe-fix
 
 
     ----- stderr -----
@@ -1427,7 +1412,7 @@ fn diff_shows_unsafe_fixes_with_opt_in() {
 #[test]
 fn diff_does_not_show_display_only_fixes_with_unsafe_fixes_enabled() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "B006", "--diff", "--unsafe-fixes"])
+        .args(["--select", "RUF903", "--diff", "--unsafe-fixes"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("def add_to_list(item, some_list=[]): ..."),
@@ -1443,10 +1428,9 @@ fn diff_does_not_show_display_only_fixes_with_unsafe_fixes_enabled() {
 #[test]
 fn diff_only_unsafe_fixes_available() {
     let mut cmd = RuffCheck::default()
-        .args(["--select", "F601", "--diff"])
+        .args(["--select", "RUF902", "--diff"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
         @r###"
     success: true
     exit_code: 0
@@ -1466,22 +1450,21 @@ fn check_extend_unsafe_fixes() -> Result<()> {
         &ruff_toml,
         r#"
 [lint]
-extend-unsafe-fixes = ["UP034"]
+extend-unsafe-fixes = ["RUF901"]
 "#,
     )?;
 
     let mut cmd = RuffCheck::default()
         .config(&ruff_toml)
-        .args(["--select", "F601,UP034"])
+        .args(["--select", "RUF901,RUF902"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
             @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
-    -:2:7: UP034 Avoid extraneous parentheses
+    -:1:1: RUF901 Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
     No fixes available (2 hidden fixes can be enabled with the `--unsafe-fixes` option).
 
@@ -1499,22 +1482,21 @@ fn check_extend_safe_fixes() -> Result<()> {
         &ruff_toml,
         r#"
 [lint]
-extend-safe-fixes = ["F601"]
+extend-safe-fixes = ["RUF902"]
 "#,
     )?;
 
     let mut cmd = RuffCheck::default()
         .config(&ruff_toml)
-        .args(["--select", "F601,UP034"])
+        .args(["--select", "RUF901,RUF902"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
             @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 [*] Dictionary key literal `'a'` repeated
-    -:2:7: UP034 [*] Avoid extraneous parentheses
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 [*] Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
     [*] 2 fixable with the `--fix` option.
 
@@ -1533,25 +1515,24 @@ fn check_extend_unsafe_fixes_conflict_with_extend_safe_fixes() -> Result<()> {
         &ruff_toml,
         r#"
 [lint]
-extend-unsafe-fixes = ["UP034"]
-extend-safe-fixes = ["UP034"]
+extend-unsafe-fixes = ["RUF902"]
+extend-safe-fixes = ["RUF902"]
 "#,
     )?;
 
     let mut cmd = RuffCheck::default()
         .config(&ruff_toml)
-        .args(["--select", "F601,UP034"])
+        .args(["--select", "RUF901,RUF902"])
         .build();
-    assert_cmd_snapshot!(cmd
-        .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\n"),
+    assert_cmd_snapshot!(cmd,
             @r###"
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
-    -:2:7: UP034 Avoid extraneous parentheses
+    -:1:1: RUF901 [*] Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 Hey this is a stable test rule with an unsafe fix.
     Found 2 errors.
-    No fixes available (2 hidden fixes can be enabled with the `--unsafe-fixes` option).
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     "###);
@@ -1569,14 +1550,14 @@ fn check_extend_unsafe_fixes_conflict_with_extend_safe_fixes_by_specificity() ->
         r#"
 target-version = "py310"
 [lint]
-extend-unsafe-fixes = ["UP", "UP034"]
-extend-safe-fixes = ["UP03"]
+extend-unsafe-fixes = ["RUF", "RUF901"]
+extend-safe-fixes = ["RUF9"]
 "#,
     )?;
 
     let mut cmd = RuffCheck::default()
         .config(&ruff_toml)
-        .args(["--select", "F601,UP018,UP034,UP038"])
+        .args(["--select", "RUF9"])
         .build();
     assert_cmd_snapshot!(cmd
         .pass_stdin("x = {'a': 1, 'a': 1}\nprint(('foo'))\nprint(str('foo'))\nisinstance(x, (int, str))\n"),
@@ -1584,12 +1565,12 @@ extend-safe-fixes = ["UP03"]
     success: false
     exit_code: 1
     ----- stdout -----
-    -:1:14: F601 Dictionary key literal `'a'` repeated
-    -:2:7: UP034 Avoid extraneous parentheses
-    -:3:7: UP018 Unnecessary `str` call (rewrite as a literal)
-    -:4:1: UP038 [*] Use `X | Y` in `isinstance` call instead of `(X, Y)`
+    -:1:1: RUF900 Hey this is a stable test rule.
+    -:1:1: RUF901 Hey this is a stable test rule with a safe fix.
+    -:1:1: RUF902 [*] Hey this is a stable test rule with an unsafe fix.
+    -:1:1: RUF903 Hey this is a stable test rule with a display only fix.
     Found 4 errors.
-    [*] 1 fixable with the `--fix` option (3 hidden fixes can be enabled with the `--unsafe-fixes` option).
+    [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
     "###);
diff --git a/crates/ruff_linter/Cargo.toml b/crates/ruff_linter/Cargo.toml
index 00f0b3d82a548..4fd4dc77f0f7d 100644
--- a/crates/ruff_linter/Cargo.toml
+++ b/crates/ruff_linter/Cargo.toml
@@ -85,6 +85,8 @@ tempfile = { workspace = true }
 [features]
 default = []
 schemars = ["dep:schemars"]
+# Enables rules for internal integration tests
+test-rules = []
 
 [lints]
 workspace = true
diff --git a/crates/ruff_linter/src/codes.rs b/crates/ruff_linter/src/codes.rs
index ded0fe7eeff7e..5c369809c01dd 100644
--- a/crates/ruff_linter/src/codes.rs
+++ b/crates/ruff_linter/src/codes.rs
@@ -934,6 +934,20 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Ruff, "026") => (RuleGroup::Preview, rules::ruff::rules::DefaultFactoryKwarg),
         (Ruff, "100") => (RuleGroup::Stable, rules::ruff::rules::UnusedNOQA),
         (Ruff, "200") => (RuleGroup::Stable, rules::ruff::rules::InvalidPyprojectToml),
+        #[cfg(feature = "test-rules")]
+        (Ruff, "900") => (RuleGroup::Stable, rules::ruff::rules::StableTestRule),
+        #[cfg(feature = "test-rules")]
+        (Ruff, "901") => (RuleGroup::Stable, rules::ruff::rules::StableTestRuleSafeFix),
+        #[cfg(feature = "test-rules")]
+        (Ruff, "902") => (RuleGroup::Stable, rules::ruff::rules::StableTestRuleUnsafeFix),
+        #[cfg(feature = "test-rules")]
+        (Ruff, "903") => (RuleGroup::Stable, rules::ruff::rules::StableTestRuleDisplayOnlyFix),
+        #[cfg(feature = "test-rules")]
+        (Ruff, "911") => (RuleGroup::Preview, rules::ruff::rules::PreviewTestRule),
+        #[cfg(feature = "test-rules")]
+        #[allow(deprecated)]
+        (Ruff, "912") => (RuleGroup::Nursery, rules::ruff::rules::NurseryTestRule),
+
 
         // flake8-django
         (Flake8Django, "001") => (RuleGroup::Stable, rules::flake8_django::rules::DjangoNullableModelStringField),
diff --git a/crates/ruff_linter/src/linter.rs b/crates/ruff_linter/src/linter.rs
index af7baf4f7d8f9..003edc4446198 100644
--- a/crates/ruff_linter/src/linter.rs
+++ b/crates/ruff_linter/src/linter.rs
@@ -33,6 +33,8 @@ use crate::message::Message;
 use crate::noqa::add_noqa;
 use crate::registry::{AsRule, Rule, RuleSet};
 use crate::rules::pycodestyle;
+#[cfg(feature = "test-rules")]
+use crate::rules::ruff::rules::test_rules::{self, TestRule, TEST_RULES};
 use crate::settings::types::UnsafeFixes;
 use crate::settings::{flags, LinterSettings};
 use crate::source_kind::SourceKind;
@@ -214,6 +216,34 @@ pub fn check_path(
         ));
     }
 
+    // Raise violations for internal test rules
+    #[cfg(feature = "test-rules")]
+    {
+        for test_rule in TEST_RULES {
+            if !settings.rules.enabled(*test_rule) {
+                continue;
+            }
+            let diagnostic = match test_rule {
+                Rule::StableTestRule => test_rules::StableTestRule::diagnostic(locator, indexer),
+                Rule::StableTestRuleSafeFix => {
+                    test_rules::StableTestRuleSafeFix::diagnostic(locator, indexer)
+                }
+                Rule::StableTestRuleUnsafeFix => {
+                    test_rules::StableTestRuleUnsafeFix::diagnostic(locator, indexer)
+                }
+                Rule::StableTestRuleDisplayOnlyFix => {
+                    test_rules::StableTestRuleDisplayOnlyFix::diagnostic(locator, indexer)
+                }
+                Rule::NurseryTestRule => test_rules::NurseryTestRule::diagnostic(locator, indexer),
+                Rule::PreviewTestRule => test_rules::PreviewTestRule::diagnostic(locator, indexer),
+                _ => unreachable!("All test rules must have an implementation"),
+            };
+            if let Some(diagnostic) = diagnostic {
+                diagnostics.push(diagnostic);
+            }
+        }
+    }
+
     // Ignore diagnostics based on per-file-ignores.
     let per_file_ignores = if !diagnostics.is_empty() && !settings.per_file_ignores.is_empty() {
         fs::ignores_from_path(path, &settings.per_file_ignores)
@@ -539,7 +569,7 @@ pub fn lint_fix<'a>(
                 // Increment the iteration count.
                 iterations += 1;
 
-                // Re-run the linter pass (by avoiding the break).
+                // Re-run the linter pass (by avoiding the return).
                 continue;
             }
 
diff --git a/crates/ruff_linter/src/rules/ruff/rules/mod.rs b/crates/ruff_linter/src/rules/ruff/rules/mod.rs
index 7a2f8dc2f7fdc..4d245b5da844a 100644
--- a/crates/ruff_linter/src/rules/ruff/rules/mod.rs
+++ b/crates/ruff_linter/src/rules/ruff/rules/mod.rs
@@ -18,6 +18,8 @@ pub(crate) use quadratic_list_summation::*;
 pub(crate) use sort_dunder_all::*;
 pub(crate) use sort_dunder_slots::*;
 pub(crate) use static_key_dict_comprehension::*;
+#[cfg(feature = "test-rules")]
+pub(crate) use test_rules::*;
 pub(crate) use unnecessary_dict_comprehension_for_iterable::*;
 pub(crate) use unnecessary_iterable_allocation_for_first_element::*;
 pub(crate) use unnecessary_key_check::*;
@@ -45,6 +47,8 @@ mod sequence_sorting;
 mod sort_dunder_all;
 mod sort_dunder_slots;
 mod static_key_dict_comprehension;
+#[cfg(feature = "test-rules")]
+pub(crate) mod test_rules;
 mod unnecessary_dict_comprehension_for_iterable;
 mod unnecessary_iterable_allocation_for_first_element;
 mod unnecessary_key_check;
diff --git a/crates/ruff_linter/src/rules/ruff/rules/test_rules.rs b/crates/ruff_linter/src/rules/ruff/rules/test_rules.rs
new file mode 100644
index 0000000000000..5a78526f663dc
--- /dev/null
+++ b/crates/ruff_linter/src/rules/ruff/rules/test_rules.rs
@@ -0,0 +1,291 @@
+/// Fake rules for testing Ruff's behavior
+///
+/// All of these rules should be assigned to the RUF9XX codes.
+///
+/// Implementing a new test rule involves:
+///
+/// - Writing an empty struct for the rule
+/// - Adding to the rule registry
+/// - Adding to the `TEST_RULES` constant
+/// - Implementing `Violation` for the rule
+/// - Implementing `TestRule` for the rule
+/// - Adding a match arm in `linter::check_path`
+///
+/// Rules that provide a fix _must_ not raise unconditionally or the linter
+/// will not converge.
+use ruff_diagnostics::{Diagnostic, Edit, Fix, FixAvailability, Violation};
+use ruff_macros::{derive_message_formats, violation};
+use ruff_python_index::Indexer;
+use ruff_source_file::Locator;
+use ruff_text_size::TextSize;
+
+use crate::registry::Rule;
+
+/// Check if a comment exists anywhere in a the given file
+fn comment_exists(text: &str, locator: &Locator, indexer: &Indexer) -> bool {
+    for range in indexer.comment_ranges() {
+        let comment_text = locator.slice(range);
+        if text.trim_end() == comment_text {
+            return true;
+        }
+    }
+    false
+}
+
+pub(crate) const TEST_RULES: &[Rule] = &[
+    Rule::StableTestRule,
+    Rule::StableTestRuleSafeFix,
+    Rule::StableTestRuleUnsafeFix,
+    Rule::StableTestRuleDisplayOnlyFix,
+    Rule::PreviewTestRule,
+    Rule::NurseryTestRule,
+];
+
+pub(crate) trait TestRule {
+    fn diagnostic(locator: &Locator, indexer: &Indexer) -> Option<Diagnostic>;
+}
+
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct StableTestRule;
+
+impl Violation for StableTestRule {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::None;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a stable test rule.")
+    }
+}
+
+impl TestRule for StableTestRule {
+    fn diagnostic(_locator: &Locator, _indexer: &Indexer) -> Option<Diagnostic> {
+        Some(Diagnostic::new(
+            StableTestRule,
+            ruff_text_size::TextRange::default(),
+        ))
+    }
+}
+
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct StableTestRuleSafeFix;
+
+impl Violation for StableTestRuleSafeFix {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Always;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a stable test rule with a safe fix.")
+    }
+}
+
+impl TestRule for StableTestRuleSafeFix {
+    fn diagnostic(locator: &Locator, indexer: &Indexer) -> Option<Diagnostic> {
+        let comment = format!("# fix from stable-test-rule-safe-fix\n");
+        if comment_exists(&comment, locator, indexer) {
+            None
+        } else {
+            Some(
+                Diagnostic::new(StableTestRuleSafeFix, ruff_text_size::TextRange::default())
+                    .with_fix(Fix::safe_edit(Edit::insertion(
+                        comment.to_string(),
+                        TextSize::new(0),
+                    ))),
+            )
+        }
+    }
+}
+
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct StableTestRuleUnsafeFix;
+
+impl Violation for StableTestRuleUnsafeFix {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Always;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a stable test rule with an unsafe fix.")
+    }
+}
+
+impl TestRule for StableTestRuleUnsafeFix {
+    fn diagnostic(locator: &Locator, indexer: &Indexer) -> Option<Diagnostic> {
+        let comment = format!("# fix from stable-test-rule-unsafe-fix\n");
+        if comment_exists(&comment, locator, indexer) {
+            None
+        } else {
+            Some(
+                Diagnostic::new(
+                    StableTestRuleUnsafeFix,
+                    ruff_text_size::TextRange::default(),
+                )
+                .with_fix(Fix::unsafe_edit(Edit::insertion(
+                    comment.to_string(),
+                    TextSize::new(0),
+                ))),
+            )
+        }
+    }
+}
+
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct StableTestRuleDisplayOnlyFix;
+
+impl Violation for StableTestRuleDisplayOnlyFix {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Always;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a stable test rule with a display only fix.")
+    }
+}
+
+impl TestRule for StableTestRuleDisplayOnlyFix {
+    fn diagnostic(locator: &Locator, indexer: &Indexer) -> Option<Diagnostic> {
+        let comment = format!("# fix from stable-test-rule-display-only-fix\n");
+        if comment_exists(&comment, locator, indexer) {
+            None
+        } else {
+            Some(
+                Diagnostic::new(
+                    StableTestRuleDisplayOnlyFix,
+                    ruff_text_size::TextRange::default(),
+                )
+                .with_fix(Fix::display_only_edit(Edit::insertion(
+                    comment.to_string(),
+                    TextSize::new(0),
+                ))),
+            )
+        }
+    }
+}
+
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct PreviewTestRule;
+
+impl Violation for PreviewTestRule {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::None;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a preview test rule.")
+    }
+}
+
+impl TestRule for PreviewTestRule {
+    fn diagnostic(_locator: &Locator, _indexer: &Indexer) -> Option<Diagnostic> {
+        Some(Diagnostic::new(
+            PreviewTestRule,
+            ruff_text_size::TextRange::default(),
+        ))
+    }
+}
+/// ## What it does
+/// Fake rule for testing.
+///
+/// ## Why is this bad?
+/// Tests must pass!
+///
+/// ## Example
+/// ```python
+/// foo
+/// ```
+///
+/// Use instead:
+/// ```python
+/// bar
+/// ```
+#[violation]
+pub struct NurseryTestRule;
+
+impl Violation for NurseryTestRule {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::None;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("Hey this is a nursery test rule.")
+    }
+}
+
+impl TestRule for NurseryTestRule {
+    fn diagnostic(_locator: &Locator, _indexer: &Indexer) -> Option<Diagnostic> {
+        Some(Diagnostic::new(
+            NurseryTestRule,
+            ruff_text_size::TextRange::default(),
+        ))
+    }
+}
diff --git a/crates/ruff_macros/src/map_codes.rs b/crates/ruff_macros/src/map_codes.rs
index 3a68af8e25258..e81fac4cdd33e 100644
--- a/crates/ruff_macros/src/map_codes.rs
+++ b/crates/ruff_macros/src/map_codes.rs
@@ -8,7 +8,7 @@ use syn::{
     Ident, ItemFn, LitStr, Pat, Path, Stmt, Token,
 };
 
-use crate::rule_code_prefix::{get_prefix_ident, if_all_same};
+use crate::rule_code_prefix::{get_prefix_ident, intersection_all};
 
 /// A rule entry in the big match statement such a
 /// `(Pycodestyle, "E112") => (RuleGroup::Nursery, rules::pycodestyle::rules::logical_lines::NoIndentedBlock),`
@@ -142,12 +142,13 @@ pub(crate) fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
 
         for (prefix, rules) in &rules_by_prefix {
             let prefix_ident = get_prefix_ident(prefix);
-            let attr = match if_all_same(rules.iter().map(|(.., attrs)| attrs)) {
-                Some(attr) => quote!(#(#attr)*),
-                None => quote!(),
+            let attrs = intersection_all(rules.iter().map(|(.., attrs)| attrs.as_slice()));
+            let attrs = match attrs.as_slice() {
+                [] => quote!(),
+                [..] => quote!(#(#attrs)*),
             };
             all_codes.push(quote! {
-                #attr Self::#linter(#linter::#prefix_ident)
+                #attrs Self::#linter(#linter::#prefix_ident)
             });
         }
 
@@ -159,12 +160,13 @@ pub(crate) fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
                 quote!(#(#attrs)* Rule::#rule_name)
             });
             let prefix_ident = get_prefix_ident(&prefix);
-            let attr = match if_all_same(rules.iter().map(|(.., attrs)| attrs)) {
-                Some(attr) => quote!(#(#attr)*),
-                None => quote!(),
+            let attrs = intersection_all(rules.iter().map(|(.., attrs)| attrs.as_slice()));
+            let attrs = match attrs.as_slice() {
+                [] => quote!(),
+                [..] => quote!(#(#attrs)*),
             };
             prefix_into_iter_match_arms.extend(quote! {
-                #attr #linter::#prefix_ident => vec![#(#rule_paths,)*].into_iter(),
+                #attrs #linter::#prefix_ident => vec![#(#rule_paths,)*].into_iter(),
             });
         }
 
diff --git a/crates/ruff_macros/src/rule_code_prefix.rs b/crates/ruff_macros/src/rule_code_prefix.rs
index 89c7543c5b325..04d9f9b1fa42e 100644
--- a/crates/ruff_macros/src/rule_code_prefix.rs
+++ b/crates/ruff_macros/src/rule_code_prefix.rs
@@ -89,21 +89,30 @@ fn attributes_for_prefix(
     codes: &BTreeSet<String>,
     attributes: &BTreeMap<String, &[Attribute]>,
 ) -> proc_macro2::TokenStream {
-    match if_all_same(codes.iter().map(|code| attributes[code])) {
-        Some(attr) => quote!(#(#attr)*),
-        None => quote!(),
+    let attrs = intersection_all(codes.iter().map(|code| attributes[code]));
+    match attrs.as_slice() {
+        [] => quote!(),
+        [..] => quote!(#(#attrs)*),
     }
 }
 
-/// If all values in an iterator are the same, return that value. Otherwise,
-/// return `None`.
-pub(crate) fn if_all_same<T: PartialEq>(iter: impl Iterator<Item = T>) -> Option<T> {
-    let mut iter = iter.peekable();
-    let first = iter.next()?;
-    if iter.all(|x| x == first) {
-        Some(first)
+/// Collect all the items from an iterable of slices that are present in all slices.
+pub(crate) fn intersection_all<'a, T: PartialEq>(
+    mut slices: impl Iterator<Item = &'a [T]>,
+) -> Vec<&'a T> {
+    if let Some(slice) = slices.next() {
+        // Collect all the items in the first slice
+        let mut intersection = Vec::with_capacity(slice.len());
+        for item in slice {
+            intersection.push(item);
+        }
+        // Then only keep items that are present in each of the remaining slices
+        for slice in slices {
+            intersection.retain(|item| slice.contains(item));
+        }
+        intersection
     } else {
-        None
+        Vec::new()
     }
 }
 
diff --git a/crates/ruff_workspace/Cargo.toml b/crates/ruff_workspace/Cargo.toml
index b7781678bf0b4..809fc227b6df3 100644
--- a/crates/ruff_workspace/Cargo.toml
+++ b/crates/ruff_workspace/Cargo.toml
@@ -42,6 +42,8 @@ strum = { workspace = true }
 toml = { workspace = true }
 
 [dev-dependencies]
+# Enable test rules during development
+ruff_linter = { path = "../ruff_linter", features = ["clap", "test-rules"] }
 tempfile = { workspace = true }
 
 [features]
diff --git a/crates/ruff_workspace/src/configuration.rs b/crates/ruff_workspace/src/configuration.rs
index f759febfccb7a..fbaeec25228ce 100644
--- a/crates/ruff_workspace/src/configuration.rs
+++ b/crates/ruff_workspace/src/configuration.rs
@@ -1184,6 +1184,7 @@ mod tests {
         Rule::DeleteFullSlice,
         Rule::CheckAndRemoveFromSet,
         Rule::QuadraticListSummation,
+        Rule::NurseryTestRule,
     ];
 
     const PREVIEW_RULES: &[Rule] = &[
@@ -1201,6 +1202,7 @@ mod tests {
         Rule::UndocumentedWarn,
         Rule::UnnecessaryEnumerate,
         Rule::MathConstant,
+        Rule::PreviewTestRule,
     ];
 
     #[allow(clippy::needless_pass_by_value)]
diff --git a/python/ruff-ecosystem/ruff_ecosystem/projects.py b/python/ruff-ecosystem/ruff_ecosystem/projects.py
index fc0139c7d1e14..4ed46565d82d7 100644
--- a/python/ruff-ecosystem/ruff_ecosystem/projects.py
+++ b/python/ruff-ecosystem/ruff_ecosystem/projects.py
@@ -206,6 +206,9 @@ def to_ruff_args(self) -> list[str]:
             "check",
             "--no-cache",
             "--exit-zero",
+            # Ignore internal test rules
+            "--ignore",
+            "RUF9",
             f"--{'' if self.preview else 'no-'}preview",
         ]
         if self.select: