diff --git a/CLAUDE.md b/CLAUDE.md
index 636e685f20..c0163e3043 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:** 0.5.1309
+**Current Version:** 0.5.1310
 
 
 ## TypeScript Parity Status
diff --git a/Cargo.lock b/Cargo.lock
index 7eac6d952b..3e9d9864c2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5547,7 +5547,7 @@ checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
 [[package]]
 name = "perry"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "base64",
@@ -5607,14 +5607,14 @@ dependencies = [
 
 [[package]]
 name = "perry-api-manifest"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "serde",
 ]
 
 [[package]]
 name = "perry-audio-miniaudio"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "cc",
  "libc",
@@ -5622,7 +5622,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "inkwell",
@@ -5639,7 +5639,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-arkts"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5647,7 +5647,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-glance"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5655,7 +5655,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-js"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-dispatch",
@@ -5664,7 +5664,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-swiftui"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5672,7 +5672,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wasm"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "base64",
@@ -5684,7 +5684,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wear-tiles"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5692,7 +5692,7 @@ dependencies = [
 
 [[package]]
 name = "perry-container-compose"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -5721,14 +5721,14 @@ dependencies = [
 
 [[package]]
 name = "perry-container-e2e"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
 ]
 
 [[package]]
 name = "perry-diagnostics"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "serde",
  "serde_json",
@@ -5736,7 +5736,7 @@ dependencies = [
 
 [[package]]
 name = "perry-dispatch"
-version = "0.5.1309"
+version = "0.5.1310"
 
 [[package]]
 name = "perry-doc-fixture-my-bindings"
@@ -5747,7 +5747,7 @@ dependencies = [
 
 [[package]]
 name = "perry-doc-tests"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "clap",
@@ -5762,7 +5762,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ads"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "block2",
  "objc2",
@@ -5772,7 +5772,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-argon2"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "argon2",
  "perry-ffi",
@@ -5780,7 +5780,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-axios"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "reqwest",
@@ -5789,7 +5789,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-bcrypt"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bcrypt",
  "perry-ffi",
@@ -5797,7 +5797,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-better-sqlite3"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "rusqlite",
@@ -5805,7 +5805,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cheerio"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "scraper",
@@ -5813,7 +5813,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-commander"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5821,7 +5821,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cron"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "chrono",
  "cron",
@@ -5831,7 +5831,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dayjs"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5839,7 +5839,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-decimal"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "rust_decimal",
@@ -5847,7 +5847,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dotenv"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "serde_json",
@@ -5855,7 +5855,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ethers"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "rand 0.10.1",
@@ -5863,7 +5863,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-events"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5871,14 +5871,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-exponential-backoff"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-fastify"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bytes",
  "http-body-util",
@@ -5896,7 +5896,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-fetch"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bytes",
  "lazy_static",
@@ -5909,7 +5909,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-http"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bytes",
  "h2",
@@ -5933,7 +5933,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ioredis"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -5943,7 +5943,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-jsonwebtoken"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "jsonwebtoken",
@@ -5954,7 +5954,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-lru-cache"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "lru",
  "perry-ffi",
@@ -5963,7 +5963,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-moment"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5971,7 +5971,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mongodb"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bson",
  "futures-util",
@@ -5983,7 +5983,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mysql2"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5993,7 +5993,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nanoid"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "nanoid",
  "perry-ffi",
@@ -6002,7 +6002,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-net"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "bytes",
  "perry-ffi",
@@ -6015,7 +6015,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-node-forge"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "const-oid 0.9.6",
  "der 0.7.10",
@@ -6034,7 +6034,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nodemailer"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "lettre",
  "perry-ffi",
@@ -6044,7 +6044,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pdf"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "printpdf",
@@ -6052,7 +6052,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pg"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "sqlx",
@@ -6061,7 +6061,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ratelimit"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "governor",
  "perry-ffi",
@@ -6069,7 +6069,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-sharp"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "fast_image_resize",
  "image",
@@ -6079,14 +6079,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-slugify"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-streams"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -6095,7 +6095,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-undici"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -6104,7 +6104,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-uuid"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "uuid",
@@ -6112,7 +6112,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-validator"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ffi",
  "regex",
@@ -6122,7 +6122,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ws"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "futures-util",
  "lazy_static",
@@ -6135,7 +6135,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-zlib"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "brotli",
  "flate2",
@@ -6145,7 +6145,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ffi"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "dashmap",
  "once_cell",
@@ -6154,7 +6154,7 @@ dependencies = [
 
 [[package]]
 name = "perry-hir"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-api-manifest",
@@ -6172,7 +6172,7 @@ dependencies = [
 
 [[package]]
 name = "perry-parser"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-diagnostics",
@@ -6184,7 +6184,7 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "base64",
@@ -6226,14 +6226,14 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime-static"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-runtime",
 ]
 
 [[package]]
 name = "perry-stdlib"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "aes 0.8.4",
  "aes 0.9.1",
@@ -6328,14 +6328,14 @@ dependencies = [
 
 [[package]]
 name = "perry-stdlib-static"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-stdlib",
 ]
 
 [[package]]
 name = "perry-transform"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -6344,14 +6344,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ui-model",
 ]
 
 [[package]]
 name = "perry-ui-android"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "itoa",
@@ -6368,7 +6368,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-geisterhand"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "rand 0.10.1",
  "serde",
@@ -6378,7 +6378,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-gtk4"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "cairo-rs 0.22.0",
@@ -6401,7 +6401,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-ios"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "block2",
@@ -6417,7 +6417,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-macos"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "block2",
@@ -6432,7 +6432,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-model"
-version = "0.5.1309"
+version = "0.5.1310"
 
 [[package]]
 name = "perry-ui-test"
@@ -6443,11 +6443,11 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-testkit"
-version = "0.5.1309"
+version = "0.5.1310"
 
 [[package]]
 name = "perry-ui-tvos"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "block2",
@@ -6463,7 +6463,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-visionos"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "block2",
@@ -6479,7 +6479,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-watchos"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "block2",
  "libc",
@@ -6492,7 +6492,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "base64",
  "libc",
@@ -6509,14 +6509,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows-winui"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "perry-ui-windows",
 ]
 
 [[package]]
 name = "perry-updater"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "anyhow",
  "base64",
@@ -6532,7 +6532,7 @@ dependencies = [
 
 [[package]]
 name = "perry-wasm-host"
-version = "0.5.1309"
+version = "0.5.1310"
 dependencies = [
  "wasmi",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 5a21b29397..32f8478d57 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -315,7 +315,7 @@ codegen-units = 16
 codegen-units = 16
 
 [workspace.package]
-version = "0.5.1309"
+version = "0.5.1310"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/PerryTS/perry"
diff --git a/changelog.d/7549-cache-oldgen-liveness-assertion.md b/changelog.d/7549-cache-oldgen-liveness-assertion.md
new file mode 100644
index 0000000000..98a2fd7442
--- /dev/null
+++ b/changelog.d/7549-cache-oldgen-liveness-assertion.md
@@ -0,0 +1,16 @@
+### Tests: assert the sparse cache is old-gen before testing the containment branch
+
+#7546's external-edge test asserted that the lazy array's sparse cache and its
+header land on different pages, but never that the cache block is **old-gen**.
+
+`slot_is_external_to` short-circuits to `true` on generation *before* it
+reaches the containment test. So if an allocator change ever moved a 32 KiB
+sparse cache into the nursery, the containment branch this test exists to cover
+would quietly stop running — and the test would still pass. That is CLAUDE.md's
+"a gate must assert its subject was live" hazard, applied to a test that was
+itself written to close a coverage hole of exactly that kind (#7500's
+`test_dirty_lazy_array_external_cache_scan_marks_bitmap_selected_child` was
+green for its whole life because no producer ever wrote a real entry).
+
+Adds the missing precondition. Raised by CodeRabbit on #7546; applied here
+because the reviewing agent's worktree was removed before it could.
diff --git a/crates/perry-runtime/src/gc/tests/runtime_roots/callback_scanners.rs b/crates/perry-runtime/src/gc/tests/runtime_roots/callback_scanners.rs
index 3dc4707636..bf098d1360 100644
--- a/crates/perry-runtime/src/gc/tests/runtime_roots/callback_scanners.rs
+++ b/crates/perry-runtime/src/gc/tests/runtime_roots/callback_scanners.rs
@@ -369,6 +369,19 @@ fn test_json_tape_lazy_get_records_its_cache_store_as_an_external_edge() {
             header_from_user_ptr(hdr as *const u8) as usize,
         )
     };
+    // #7549: assert the cache block is OLD-GEN before asserting anything about
+    // pages. `slot_is_external_to` short-circuits to `true` on generation
+    // BEFORE it reaches the containment test — so if an allocator change ever
+    // moved a 32 KiB sparse cache into the nursery, the containment branch this
+    // test exists to cover would quietly stop running and the test would still
+    // pass. That is the "a gate must assert its subject was live" hazard
+    // (CLAUDE.md) applied to this test itself. Raised by CodeRabbit on #7546.
+    assert!(
+        crate::arena::pointer_in_old_gen(cache_slot),
+        "the sparse cache must be born old, or `slot_is_external_to` \
+         short-circuits on generation and the containment branch under test \
+         never runs"
+    );
     assert_ne!(
         crate::arena::generation_page_for_addr(cache_slot),
         crate::arena::generation_page_for_addr(hdr as usize),