diff --git a/README.md b/README.md
index fcc27f4..31778d6 100644
--- a/README.md
+++ b/README.md
@@ -139,7 +139,7 @@ allow_write = ["/tmp/build"]
 pass_env = ["NODE_ENV", "DEBUG"]
 ```
 
-Custom profiles go in `~/.config/sx/profiles/name.toml`.
+Custom profiles go in `~/.config/sx/profiles/name.toml`. They support filesystem paths, env vars, exec sugid, and raw seatbelt rules for advanced sandbox operations. See [docs/PROFILES.md](docs/PROFILES.md).
 
 ## Usage
 
diff --git a/docs/CONFIGURATION.md b/docs/CONFIGURATION.md
index ba0ddc9..322f862 100644
--- a/docs/CONFIGURATION.md
+++ b/docs/CONFIGURATION.md
@@ -80,6 +80,22 @@ pass_env = ["MYPROJECT_TOKEN"]
 
 Use with `sx myproject -- command`.
 
+Custom profiles also support raw seatbelt rules for advanced sandbox operations (IOKit, Mach services, app bundles):
+
+```toml
+# ~/.config/sx/profiles/playwright.toml
+network_mode = "online"
+
+[seatbelt]
+raw = """
+(allow iokit-open-user-client
+  (iokit-user-client-class "RootDomainUserClient"))
+(allow iokit-get-properties)
+"""
+```
+
+Raw rules from all active profiles are concatenated in order. See [PROFILES.md](PROFILES.md) for details.
+
 ## Setuid/Setgid Execution
 
 Some binaries like `/bin/ps` are setuid/setgid. Seatbelt blocks these by default with `forbidden-exec-sugid`. Use `allow_exec_sugid` to opt in.
diff --git a/docs/PROFILES.md b/docs/PROFILES.md
index bfeda1d..a14170a 100644
--- a/docs/PROFILES.md
+++ b/docs/PROFILES.md
@@ -116,6 +116,40 @@ Use it:
 sx mycompany -- ./run.sh
 ```
 
+### Raw Seatbelt Rules
+
+For advanced use cases (IOKit, Mach services, app bundles), custom profiles support raw seatbelt rules:
+
+```toml
+# ~/.config/sx/profiles/playwright.toml
+network_mode = "online"
+
+[seatbelt]
+raw = """
+(allow iokit-open-user-client
+  (iokit-user-client-class "RootDomainUserClient")
+  (iokit-user-client-class "AGXDeviceUserClient")
+  (iokit-user-client-class "IOSurfaceRootUserClient"))
+(allow iokit-get-properties)
+(allow file-issue-extension)
+"""
+
+[filesystem]
+allow_read = ["~/Library/Caches/ms-playwright/"]
+allow_write = ["~/Library/Caches/ms-playwright/"]
+```
+
+Raw rules are appended verbatim to the generated seatbelt profile. Use `sx --dry-run myprofile` to verify the output.
+
+### Profile Resolution Order
+
+When you specify a profile name, `sx` searches in this order:
+
+1. **Built-in profiles** (embedded in the binary)
+2. **Project custom directory** (if configured)
+3. **`~/.config/sx/profiles/{name}.toml`**
+4. **Fallback** to `online` with a warning if not found
+
 ## Project Profiles
 
 In `.sandbox.toml`:
@@ -131,3 +165,4 @@ profiles = ["rust", "localhost"]
 2. **Filesystem paths:** union (no duplicates)
 3. **Env vars:** union of pass/deny lists
 4. **Exec sugid:** path lists are unioned; mixing paths and booleans → last wins
+5. **Seatbelt raw rules:** concatenated from all profiles in order
diff --git a/src/config/profile.rs b/src/config/profile.rs
index c9f0972..fb55fd5 100644
--- a/src/config/profile.rs
+++ b/src/config/profile.rs
@@ -207,10 +207,11 @@ pub fn load_profiles(names: &[String], custom_dir: Option<&Path>) -> Vec<Profile
                 }
             }
 
-            // Try global profile directory
-            if let Some(config_dir) = dirs::config_dir() {
-                let path = config_dir
-                    .join("sx/profiles")
+            // Try global profile directory (~/.config/sx/profiles/)
+            // Uses ~/.config to match global config path (global.rs)
+            if let Some(home) = dirs::home_dir() {
+                let path = home
+                    .join(".config/sx/profiles")
                     .join(format!("{}.toml", name));
                 if path.exists() {
                     match load_profile(&path) {
@@ -297,6 +298,20 @@ pub fn compose_profiles(profiles: &[Profile]) -> Profile {
                 }
             }
         }
+
+        // Seatbelt: concatenate raw rules from all profiles
+        if let Some(seatbelt) = &profile.seatbelt {
+            if let Some(raw) = &seatbelt.raw {
+                let existing = result.seatbelt.get_or_insert_with(ProfileSeatbelt::default);
+                match &mut existing.raw {
+                    Some(current) => {
+                        current.push('\n');
+                        current.push_str(raw);
+                    }
+                    None => existing.raw = Some(raw.clone()),
+                }
+            }
+        }
     }
 
     result
diff --git a/tests/profile_test.rs b/tests/profile_test.rs
index ad78d65..4f1fc7c 100644
--- a/tests/profile_test.rs
+++ b/tests/profile_test.rs
@@ -1,4 +1,6 @@
-use sx::config::profile::{compose_profiles, load_profile, load_profiles, BuiltinProfile, Profile};
+use sx::config::profile::{
+    compose_profiles, load_profile, load_profiles, BuiltinProfile, Profile, ProfileSeatbelt,
+};
 use sx::config::schema::{ExecSugid, NetworkMode};
 use tempfile::TempDir;
 
@@ -327,3 +329,55 @@ fn test_compose_profiles_exec_sugid_bool_overrides_paths() {
     let composed = compose_profiles(&[p1, p2]);
     assert_eq!(composed.allow_exec_sugid, Some(ExecSugid::Allow(true)));
 }
+
+// === Seatbelt Profile Compose Tests ===
+
+#[test]
+fn test_compose_profiles_seatbelt_single() {
+    let p = Profile {
+        seatbelt: Some(ProfileSeatbelt {
+            raw: Some("(allow iokit-get-properties)".into()),
+        }),
+        ..Default::default()
+    };
+    let composed = compose_profiles(&[p]);
+    let raw = composed.seatbelt.unwrap().raw.unwrap();
+    assert_eq!(raw, "(allow iokit-get-properties)");
+}
+
+#[test]
+fn test_compose_profiles_seatbelt_concatenation() {
+    let p1 = Profile {
+        seatbelt: Some(ProfileSeatbelt {
+            raw: Some("(allow iokit-get-properties)".into()),
+        }),
+        ..Default::default()
+    };
+    let p2 = Profile {
+        seatbelt: Some(ProfileSeatbelt {
+            raw: Some("(allow file-issue-extension)".into()),
+        }),
+        ..Default::default()
+    };
+    let composed = compose_profiles(&[p1, p2]);
+    let raw = composed.seatbelt.unwrap().raw.unwrap();
+    assert!(raw.contains("(allow iokit-get-properties)"));
+    assert!(raw.contains("(allow file-issue-extension)"));
+}
+
+#[test]
+fn test_compose_profiles_seatbelt_none_skipped() {
+    let p1 = Profile {
+        seatbelt: Some(ProfileSeatbelt {
+            raw: Some("(allow iokit-get-properties)".into()),
+        }),
+        ..Default::default()
+    };
+    let p2 = Profile {
+        seatbelt: None,
+        ..Default::default()
+    };
+    let composed = compose_profiles(&[p1, p2]);
+    let raw = composed.seatbelt.unwrap().raw.unwrap();
+    assert_eq!(raw, "(allow iokit-get-properties)");
+}