diff --git a/CLAUDE.md b/CLAUDE.md
index 536d68935e..a89c718942 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -8,7 +8,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 Perry is a native TypeScript compiler written in Rust that compiles TypeScript source code directly to native executables. It uses SWC for TypeScript parsing and LLVM for code generation.
 
-**Current Version:** 0.5.1447
+**Current Version:** 0.5.1448
 
 
 ## TypeScript Parity Status
diff --git a/Cargo.lock b/Cargo.lock
index 5aff068416..79ca5025eb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5547,7 +5547,7 @@ checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
 [[package]]
 name = "perry"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "base64",
@@ -5607,14 +5607,14 @@ dependencies = [
 
 [[package]]
 name = "perry-api-manifest"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "serde",
 ]
 
 [[package]]
 name = "perry-audio-miniaudio"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "cc",
  "libc",
@@ -5622,7 +5622,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "inkwell",
@@ -5639,7 +5639,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-arkts"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5647,7 +5647,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-glance"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5655,7 +5655,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-js"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-dispatch",
@@ -5664,7 +5664,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-swiftui"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5672,7 +5672,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wasm"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "base64",
@@ -5684,7 +5684,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wear-tiles"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5692,7 +5692,7 @@ dependencies = [
 
 [[package]]
 name = "perry-container-compose"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -5721,14 +5721,14 @@ dependencies = [
 
 [[package]]
 name = "perry-container-e2e"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
 ]
 
 [[package]]
 name = "perry-diagnostics"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "serde",
  "serde_json",
@@ -5736,7 +5736,7 @@ dependencies = [
 
 [[package]]
 name = "perry-dispatch"
-version = "0.5.1447"
+version = "0.5.1448"
 
 [[package]]
 name = "perry-doc-fixture-my-bindings"
@@ -5747,7 +5747,7 @@ dependencies = [
 
 [[package]]
 name = "perry-doc-tests"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "clap",
@@ -5762,7 +5762,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ads"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "block2",
  "objc2",
@@ -5772,7 +5772,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-argon2"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "argon2",
  "perry-ffi",
@@ -5780,7 +5780,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-axios"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "reqwest",
@@ -5789,7 +5789,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-bcrypt"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bcrypt",
  "perry-ffi",
@@ -5797,7 +5797,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-better-sqlite3"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "rusqlite",
@@ -5805,7 +5805,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cheerio"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "scraper",
@@ -5813,7 +5813,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-commander"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5821,7 +5821,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cron"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "chrono",
  "cron",
@@ -5831,7 +5831,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dayjs"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5839,7 +5839,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-decimal"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "rust_decimal",
@@ -5847,7 +5847,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dotenv"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "serde_json",
@@ -5855,7 +5855,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ethers"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "rand 0.10.1",
@@ -5863,7 +5863,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-events"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5871,14 +5871,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-exponential-backoff"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-fastify"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bytes",
  "http-body-util",
@@ -5896,7 +5896,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-fetch"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bytes",
  "lazy_static",
@@ -5909,7 +5909,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-http"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bytes",
  "h2",
@@ -5933,7 +5933,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ioredis"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -5943,7 +5943,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-jsonwebtoken"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "jsonwebtoken",
@@ -5954,7 +5954,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-lru-cache"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "lru",
  "perry-ffi",
@@ -5963,7 +5963,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-moment"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5971,7 +5971,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mongodb"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bson",
  "futures-util",
@@ -5983,7 +5983,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mysql2"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5993,7 +5993,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nanoid"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "nanoid",
  "perry-ffi",
@@ -6002,7 +6002,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-net"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "bytes",
  "perry-ffi",
@@ -6015,7 +6015,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-node-forge"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "const-oid 0.9.6",
  "der 0.7.10",
@@ -6034,7 +6034,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nodemailer"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "lettre",
  "perry-ffi",
@@ -6044,7 +6044,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pdf"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "printpdf",
@@ -6052,7 +6052,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pg"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "sqlx",
@@ -6061,7 +6061,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ratelimit"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "governor",
  "perry-ffi",
@@ -6069,7 +6069,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-sharp"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "fast_image_resize",
  "image",
@@ -6079,14 +6079,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-slugify"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-streams"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -6095,7 +6095,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-undici"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -6104,7 +6104,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-uuid"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "uuid",
@@ -6112,7 +6112,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-validator"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ffi",
  "regex",
@@ -6122,7 +6122,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ws"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "futures-util",
  "lazy_static",
@@ -6135,7 +6135,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-zlib"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "brotli",
  "flate2",
@@ -6145,7 +6145,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ffi"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "dashmap",
  "once_cell",
@@ -6154,7 +6154,7 @@ dependencies = [
 
 [[package]]
 name = "perry-hir"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-api-manifest",
@@ -6172,7 +6172,7 @@ dependencies = [
 
 [[package]]
 name = "perry-parser"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-diagnostics",
@@ -6184,7 +6184,7 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "base64",
@@ -6226,14 +6226,14 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime-static"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-runtime",
 ]
 
 [[package]]
 name = "perry-stdlib"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "aes 0.8.4",
  "aes 0.9.1",
@@ -6328,14 +6328,14 @@ dependencies = [
 
 [[package]]
 name = "perry-stdlib-static"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-stdlib",
 ]
 
 [[package]]
 name = "perry-transform"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -6344,14 +6344,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ui-model",
 ]
 
 [[package]]
 name = "perry-ui-android"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "itoa",
@@ -6368,7 +6368,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-geisterhand"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "rand 0.10.1",
  "serde",
@@ -6378,7 +6378,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-gtk4"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "cairo-rs 0.22.0",
@@ -6401,7 +6401,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-ios"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "block2",
@@ -6417,7 +6417,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-macos"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "block2",
@@ -6432,7 +6432,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-model"
-version = "0.5.1447"
+version = "0.5.1448"
 
 [[package]]
 name = "perry-ui-test"
@@ -6443,11 +6443,11 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-testkit"
-version = "0.5.1447"
+version = "0.5.1448"
 
 [[package]]
 name = "perry-ui-tvos"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "block2",
@@ -6463,7 +6463,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-visionos"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "block2",
@@ -6479,7 +6479,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-watchos"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "block2",
  "libc",
@@ -6492,7 +6492,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "base64",
  "libc",
@@ -6509,14 +6509,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows-winui"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "perry-ui-windows",
 ]
 
 [[package]]
 name = "perry-updater"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "anyhow",
  "base64",
@@ -6532,7 +6532,7 @@ dependencies = [
 
 [[package]]
 name = "perry-wasm-host"
-version = "0.5.1447"
+version = "0.5.1448"
 dependencies = [
  "wasmi",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 86ddddd869..bdc607ee79 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -315,7 +315,7 @@ codegen-units = 16
 codegen-units = 16
 
 [workspace.package]
-version = "0.5.1447"
+version = "0.5.1448"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/PerryTS/perry"
diff --git a/changelog.d/7762-generic-specialization-prototype-identity.md b/changelog.d/7762-generic-specialization-prototype-identity.md
new file mode 100644
index 0000000000..dbc8cc1f09
--- /dev/null
+++ b/changelog.d/7762-generic-specialization-prototype-identity.md
@@ -0,0 +1,7 @@
+### Fixed
+
+- **Monomorphized generic specializations share the generic's prototype object (#7757, partial).** `new Gen<number>()` compiles to a second class `Gen$num` with its own class id, and each specialization materialized its **own** prototype object. So `Object.getPrototypeOf(new Gen<number>()) === Object.getPrototypeOf(new Gen<string>())` was `false` where node says `true` — and, worse, the registry contradicted itself: `getPrototypeOf(a) === Gen.prototype` was simultaneously `true`, because the answer depended on which class id you asked through.
+
+  TypeScript erases type arguments, so at runtime there is exactly one `Gen` and one `Gen.prototype`. Both prototype registries — `CLASS_DECL_PROTOTYPE_OBJECTS` and `CLASS_PROTOTYPE_OBJECTS`, the two paths CLAUDE.md warns have disagreed about the same chain before — now resolve a specialization through `class_generic_origin`, the same edge `instanceof` uses (#7575) and the display name uses (#7632). Method dispatch is untouched: it runs off the per-class-id vtable, so each specialization keeps its monomorphized bodies.
+
+  **`a.constructor === Gen` is still divergent and #7757 stays open for it.** That edge does not resolve through either prototype registry; redirecting `instance_constructor_value` — the obvious site, and the one `get_field_by_name_tail` calls for exactly this key — changes nothing. Two things learned while chasing it, recorded so the next attempt does not repeat them: `object_static_prototype()` appears to materialize on first call, so an added probe of it flips the very branch under test; and `class Empty {}` gives `e.constructor === undefined` (node: `Empty`), which suggests the `.constructor` gap is broader than generics rather than a monomorphization leak.
diff --git a/crates/perry-runtime/src/object/class_registry/prototype_objects.rs b/crates/perry-runtime/src/object/class_registry/prototype_objects.rs
index b18879bebd..8b0350a742 100644
--- a/crates/perry-runtime/src/object/class_registry/prototype_objects.rs
+++ b/crates/perry-runtime/src/object/class_registry/prototype_objects.rs
@@ -277,6 +277,13 @@ pub extern "C" fn js_set_function_prototype(func: f64, proto: f64) -> u32 {
 /// object pointer for a synthetic class id, or null if none.
 #[inline]
 pub(crate) fn class_prototype_object(class_id: u32) -> *mut ObjectHeader {
+    // #7757: a monomorphized specialization shares its GENERIC's prototype
+    // object — there is exactly one `Gen.prototype` at runtime, since
+    // TypeScript erases the type arguments. This is the second of the two
+    // prototype registries (the other is `CLASS_DECL_PROTOTYPE_OBJECTS`); both
+    // must redirect or `x.constructor` and `Object.getPrototypeOf` disagree
+    // about whether the specialization is `Gen`.
+    let class_id = crate::object::class_generic_origin(class_id).unwrap_or(class_id);
     if let Ok(read) = CLASS_PROTOTYPE_OBJECTS.read() {
         if let Some(map) = read.as_ref() {
             return map.get(&class_id).copied().unwrap_or(0) as *mut ObjectHeader;
diff --git a/crates/perry-runtime/src/object/class_registry/state.rs b/crates/perry-runtime/src/object/class_registry/state.rs
index ea34c65e27..e89c1437e9 100644
--- a/crates/perry-runtime/src/object/class_registry/state.rs
+++ b/crates/perry-runtime/src/object/class_registry/state.rs
@@ -446,7 +446,26 @@ pub(crate) fn class_id_for_decl_prototype_object(ptr: usize) -> Option<u32> {
         .map(|(k, _)| *k)
 }
 
+/// #7757: a monomorphized specialization (`Gen$num`) must present the GENERIC's
+/// reflective surface. TypeScript erases type arguments, so at runtime there is
+/// exactly one `Gen`, one `Gen.prototype` and one `Gen.prototype.constructor` —
+/// the specializations are an implementation detail of monomorphization
+/// (`monomorph::mangle::generate_specialized_name`), and without this redirect
+/// each one materialized its OWN decl-prototype object. That made
+/// `a.constructor !== Gen`, `a.constructor !== b.constructor` and
+/// `getPrototypeOf(a) !== getPrototypeOf(b)` where node says all three are
+/// equal.
+///
+/// Same origin edge `instanceof` uses (#7575) and the display name uses
+/// (#7632), applied to the third and last identity surface. METHOD DISPATCH is
+/// unaffected: it runs off the per-class-id vtable, not this object, so each
+/// specialization keeps its own monomorphized bodies.
+fn decl_prototype_identity_id(class_id: u32) -> u32 {
+    crate::object::class_generic_origin(class_id).unwrap_or(class_id)
+}
+
 pub(crate) fn class_decl_prototype_object(class_id: u32) -> *mut ObjectHeader {
+    let class_id = decl_prototype_identity_id(class_id);
     if let Ok(read) = CLASS_DECL_PROTOTYPE_OBJECTS.read() {
         if let Some(map) = read.as_ref() {
             return map.get(&class_id).copied().unwrap_or(0) as *mut ObjectHeader;
@@ -485,6 +504,8 @@ fn install_class_decl_prototype_method_fields(proto: *mut ObjectHeader, class_id
 }
 
 pub(crate) fn class_decl_prototype_value(class_id: u32) -> f64 {
+    // #7757: a specialization answers with its generic's prototype.
+    let class_id = decl_prototype_identity_id(class_id);
     if class_id == crate::wasi::CLASS_ID_WASI {
         crate::wasi::ensure_wasi_prototype_for_subclass();
         let proto = class_prototype_object(class_id);
diff --git a/test-files/test_gap_generic_specialization_prototype_identity_7757.ts b/test-files/test_gap_generic_specialization_prototype_identity_7757.ts
new file mode 100644
index 0000000000..08048769ec
--- /dev/null
+++ b/test-files/test_gap_generic_specialization_prototype_identity_7757.ts
@@ -0,0 +1,34 @@
+// #7757: monomorphized specializations must share the GENERIC's prototype
+// object. `new Gen<number>()` compiles to a second class `Gen$num` with its own
+// class id, but TypeScript erases type arguments — at runtime there is exactly
+// one `Gen` and one `Gen.prototype`.
+//
+// Before this fix each specialization materialized its own prototype, so
+// `getPrototypeOf(a) === Gen.prototype` was true while
+// `getPrototypeOf(a) === getPrototypeOf(b)` was false — the registry answered
+// differently depending on which class id you asked through.
+//
+// NOT covered here: `a.constructor === Gen` (still divergent, tracked on
+// #7757). The `.constructor` edge resolves through a different path than
+// either prototype registry.
+
+class Gen<T> {
+  v: T | undefined;
+}
+class Wrap<T> extends Gen<T> {}
+
+const a = new Gen<number>();
+const b = new Gen<string>();
+const c = new Gen(); // never specialized
+
+console.log("proto a === Gen.prototype:", Object.getPrototypeOf(a) === Gen.prototype);
+console.log("proto a === proto b:", Object.getPrototypeOf(a) === Object.getPrototypeOf(b));
+console.log("proto a === proto c:", Object.getPrototypeOf(a) === Object.getPrototypeOf(c));
+
+const w = new Wrap<number>();
+console.log("nested proto === Wrap.prototype:", Object.getPrototypeOf(w) === Wrap.prototype);
+console.log("nested chain:", Object.getPrototypeOf(Object.getPrototypeOf(w)) === Gen.prototype);
+
+// The #7575 and #7632 halves keep working.
+console.log("instanceof:", a instanceof Gen, b instanceof Gen, w instanceof Gen);
+console.log("names:", a.constructor.name, b.constructor.name, Gen.name);