diff --git a/changelog.d/10210-static-getter-call-path.md b/changelog.d/10210-static-getter-call-path.md
new file mode 100644
index 0000000000..30ed28f824
--- /dev/null
+++ b/changelog.d/10210-static-getter-call-path.md
@@ -0,0 +1,12 @@
+Fix method calls inside static getters of classes that extend a call expression
+(effect v4 `class Svc extends Context.Service<Svc, Shape>()(id) {}` and
+OpenCode's `ConfigService.Service` wrapper). `this.of(x)` in such a getter threw
+"of is not a function" although reading `this.of` returned the function: the
+dynamic method-call dispatcher resolved only the static-method vtable for a
+per-evaluation class object, and the class-ref read path looked for the
+function-valued parent only on the receiver's own class. The class-object call
+arm now resolves the name exactly as the read path does (static accessors, the
+parent class object's statics, the ancestor function's swapped prototype) and
+calls the closure with `this` bound to the receiver; string- and symbol-keyed
+static reads walk the class chain for the function-valued ancestor. This
+unblocks OpenCode v1.18.30's runtime bootstrap (#10210).
diff --git a/crates/perry-runtime/src/object/field_get_set/get_field_by_name.rs b/crates/perry-runtime/src/object/field_get_set/get_field_by_name.rs
index 55910e1fd6..721af36d12 100644
--- a/crates/perry-runtime/src/object/field_get_set/get_field_by_name.rs
+++ b/crates/perry-runtime/src/object/field_get_set/get_field_by_name.rs
@@ -1461,8 +1461,13 @@ pub extern "C" fn js_object_get_field_by_name(
                     // named static off the parent closure — its OWN props
                     // (`Svc.key` → "Svc") plus, via the closure getter, its
                     // static prototype (`Svc._op` → "Tag" on TagProto).
+                    // #10210: the edge is keyed by the class that directly
+                    // `extends <function>`, which may be an ANCESTOR of this
+                    // class (`class Flags extends ConfigTag {}` where
+                    // `ConfigTag extends Context.Service()(id)`), so walk the
+                    // parent chain like `super()` dispatch does.
                     if let Some(closure_ptr) =
-                        super::super::class_registry::class_parent_closure(class_id)
+                        super::super::class_registry::parent_closure_in_chain(class_id)
                     {
                         let v = crate::closure::closure_get_dynamic_prop(closure_ptr, name);
                         let vb = JSValue::from_bits(v.to_bits());
diff --git a/crates/perry-runtime/src/object/native_call_method/primitive_methods.rs b/crates/perry-runtime/src/object/native_call_method/primitive_methods.rs
index 25f6984852..5b5a174680 100644
--- a/crates/perry-runtime/src/object/native_call_method/primitive_methods.rs
+++ b/crates/perry-runtime/src/object/native_call_method/primitive_methods.rs
@@ -359,6 +359,45 @@ pub(super) unsafe fn dispatch_primitive(
                 ));
             }
         }
+        // #10210: the name may resolve where the static-method vtable cannot
+        // see it — a static ACCESSOR whose getter returns a function
+        // (`static get layer()`), a static of a per-evaluation parent class
+        // object, or the swapped prototype of a FUNCTION-valued ancestor
+        // (effect v4 `Context.Service<..>()(id)` is `function KeyClass(){}`
+        // + `Object.setPrototypeOf(KeyClass, ServiceProto)`, and a static
+        // getter on a subclass calls `this.of(x)` with `this` = this class
+        // object). The read path already resolves all of these, so mirror
+        // the class-ref arm (#5437): read the property exactly as
+        // `const f = C.of; f.call(C, x)` would, then call it with `this`
+        // bound to the receiver. Only a closure is dispatched here; anything
+        // else keeps falling through to the generic scan and the normal
+        // not-a-function error.
+        if class_id != 0 && !method_name_ptr.is_null() && method_name_len > 0 {
+            let key = crate::string::js_string_from_bytes(
+                method_name_ptr as *const u8,
+                method_name_len as u32,
+            );
+            let receiver = JSValue::from_bits(object_handle.get_nanbox_f64().to_bits())
+                .as_pointer::<ObjectHeader>();
+            let method = js_object_get_field_by_name(receiver, key);
+            if method.is_pointer()
+                && crate::closure::is_closure_ptr(crate::value::js_nanbox_get_pointer(
+                    f64::from_bits(method.bits()),
+                ) as usize)
+            {
+                let method = root_scope.root_nanbox_u64(method.bits());
+                let receiver = object_handle.get_nanbox_f64();
+                let bound =
+                    crate::closure::clone_closure_rebind_this(method.get_nanbox_u64(), receiver);
+                let _this = ImplicitThisScope::bind(receiver);
+                let args = refreshed_args();
+                return Some(crate::closure::js_native_call_value(
+                    f64::from_bits(bound),
+                    args.as_ptr(),
+                    args.len(),
+                ));
+            }
+        }
     }
 
     // #5142: a promise can carry user-attached own expando methods.
diff --git a/crates/perry-runtime/src/symbol/get.rs b/crates/perry-runtime/src/symbol/get.rs
index 0762d90c02..1fa3794a4d 100644
--- a/crates/perry-runtime/src/symbol/get.rs
+++ b/crates/perry-runtime/src/symbol/get.rs
@@ -648,8 +648,9 @@ pub unsafe extern "C" fn js_object_get_symbol_property(obj_f64: f64, sym_f64: f6
         // the parent closure — own symbol props plus, via the closure symbol
         // getter, its static prototype (`Svc[TagTypeId]`/`Svc[EffectTypeId]`
         // live on TagProto). Recurse into the closure-aware getter so its proto
-        // walk fires.
-        if let Some(closure_ptr) = crate::object::class_parent_closure(class_id) {
+        // walk fires. #10210: the edge may sit on an ancestor class — walk
+        // the chain.
+        if let Some(closure_ptr) = crate::object::parent_closure_in_chain(class_id) {
             let closure_f64 =
                 f64::from_bits(crate::value::js_nanbox_pointer(closure_ptr as i64).to_bits());
             let v = js_object_get_symbol_property(closure_f64, sym_f64);
diff --git a/crates/perry/tests/issue_10210_static_getter_call.rs b/crates/perry/tests/issue_10210_static_getter_call.rs
new file mode 100644
index 0000000000..f156f77a80
--- /dev/null
+++ b/crates/perry/tests/issue_10210_static_getter_call.rs
@@ -0,0 +1,147 @@
+//! Regression for #10210: a static getter on a class whose `extends` clause is a
+//! call expression (effect v4's `Context.Service<..>()(id)` returns a plain
+//! `function KeyClass(){}` whose `[[Prototype]]` was swapped with
+//! `Object.setPrototypeOf`) must be able to call `this.of(x)` — the CALL path
+//! has to resolve the name wherever the READ path does (static accessors,
+//! per-evaluation parent class objects, and the function-valued ancestor's
+//! swapped prototype), and the closure-parent edge must be found on an
+//! ancestor of the receiver's class, not only on the class itself.
+
+use std::path::PathBuf;
+use std::process::Command;
+use std::sync::Once;
+
+fn perry_bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_perry"))
+}
+
+fn workspace_root() -> PathBuf {
+    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .join("../..")
+        .canonicalize()
+        .expect("canonicalize workspace root")
+}
+
+fn runtime_dir() -> PathBuf {
+    static BUILD_RUNTIME: Once = Once::new();
+    BUILD_RUNTIME.call_once(|| {
+        let cargo = std::env::var_os("CARGO").unwrap_or_else(|| "cargo".into());
+        let build = Command::new(cargo)
+            .current_dir(workspace_root())
+            .arg("build")
+            .arg("-p")
+            .arg("perry-runtime-static")
+            .arg("-p")
+            .arg("perry-stdlib-static")
+            .output()
+            .expect("build static runtime archives");
+        assert!(
+            build.status.success(),
+            "static runtime build failed\nstdout:\n{}\nstderr:\n{}",
+            String::from_utf8_lossy(&build.stdout),
+            String::from_utf8_lossy(&build.stderr)
+        );
+    });
+    let target = std::env::var_os("CARGO_TARGET_DIR")
+        .map(PathBuf::from)
+        .unwrap_or_else(|| workspace_root().join("target"));
+    target.join("debug")
+}
+
+const SOURCE: &str = r#"
+const Proto: any = { of(self: any) { return self } }
+const Key = function () {
+  function K() {}
+  Object.setPrototypeOf(K, Proto)
+  ;(K as any).isK = true
+  return function (key: string) { (K as any).key = key; return K }
+}
+const t = (name: string, f: () => any) => {
+  try { console.log(name, JSON.stringify(f())) } catch (e: any) { console.log(name, "THROW", e.message) }
+}
+// nested class + subclass, static getter calls this.of(x)
+const mk1 = (id: string) => { class T extends (Key as any)()(id) { static get g() { return (this as any).of({ n: 1 }) } }; return T as any }
+class S1 extends mk1("S1") {}
+t("N1", () => S1.g)
+// same receiver, read first then call
+const mk2 = (id: string) => { class T extends (Key as any)()(id) { static get g() { const f = (this as any).of; return [typeof f, f.call(this, { n: 2 })] } }; return T as any }
+class S2 extends mk2("S2") {}
+t("N2", () => S2.g)
+// alias `this` into a local first (opencode's `const tag = this`)
+const mk4 = (id: string) => { class T extends (Key as any)()(id) { static get g() { const tag = this as any; return tag.of({ n: 4 }) } }; return T as any }
+class S4 extends mk4("S4") {}
+t("N4", () => S4.g)
+// nested, no subclass
+t("N5", () => mk1("T5").g)
+// top-level + subclass
+class T6 extends (Key as any)()("T6") { static get g() { return (this as any).of({ n: 6 }) } }
+class S6 extends T6 {}
+t("N6", () => S6.g)
+// top-level, no subclass
+t("N7", () => T6.g)
+// the closure-parent edge sits on an ancestor: inherited reads on a grandchild
+class T8 extends (Key as any)()("T8") {}
+class S8 extends T8 {}
+t("N8", () => [S8.key, (S8 as any).isK, typeof (S8 as any).of])
+// static METHOD with the same body
+const mk10 = (id: string) => { class T extends (Key as any)()(id) { static m() { return (this as any).of({ n: 10 }) } }; return T as any }
+class S10 extends mk10("S10") {}
+t("N10", () => S10.m())
+// calling the function a static getter returns, on a class extending a call expression
+const mk11 = (id: string) => { class T extends (Key as any)()(id) { static get g() { return () => 11 } }; return T as any }
+t("M1", () => mk11("T11").g())
+// the closure returned by a static getter calls tag.of (config-service.ts shape)
+const mk12 = (id: string) => { class T extends (Key as any)()(id) { static get layer() { const tag = this as any; return () => tag.of({ n: 12 }) } }; return T as any }
+class S12 extends mk12("S12") {}
+t("M2", () => { const thunk = S12.layer; return thunk() })
+"#;
+
+const EXPECTED: &str = "N1 {\"n\":1}
+N2 [\"function\",{\"n\":2}]
+N4 {\"n\":4}
+N5 {\"n\":1}
+N6 {\"n\":6}
+N7 {\"n\":6}
+N8 [\"T8\",true,\"function\"]
+N10 {\"n\":10}
+M1 11
+M2 {\"n\":12}
+";
+
+#[test]
+fn static_getter_calls_this_of_on_call_expression_heritage() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let entry = dir.path().join("main.ts");
+    let output = dir.path().join("main_bin");
+    std::fs::write(&entry, SOURCE).expect("write entry");
+
+    let compile = Command::new(perry_bin())
+        .current_dir(dir.path())
+        .arg("compile")
+        .arg(&entry)
+        .arg("-o")
+        .arg(&output)
+        .arg("--no-cache")
+        .env("PERRY_NO_AUTO_OPTIMIZE", "1")
+        .env("PERRY_RUNTIME_DIR", runtime_dir())
+        .output()
+        .expect("run perry compile");
+    assert!(
+        compile.status.success(),
+        "perry compile failed\nstdout:\n{}\nstderr:\n{}",
+        String::from_utf8_lossy(&compile.stdout),
+        String::from_utf8_lossy(&compile.stderr)
+    );
+
+    let run = Command::new(&output)
+        .current_dir(dir.path())
+        .output()
+        .expect("run compiled binary");
+    assert!(
+        run.status.success(),
+        "compiled binary failed\nstdout:\n{}\nstderr:\n{}",
+        String::from_utf8_lossy(&run.stdout),
+        String::from_utf8_lossy(&run.stderr)
+    );
+    assert_eq!(String::from_utf8_lossy(&run.stdout), EXPECTED);
+}