diff --git a/CHANGELOG.md b/CHANGELOG.md
index 24bb51d095..ff609c7b36 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,12 @@
+## v0.5.1230 — class-capture snapshot P0 pair: resolved-name re-registration + same-body assignment tracking
+
+Two defects in the decl-site class-capture snapshot (`js_class_register_capture_values`), both extracted from the #5437 Next.js branch:
+
+1. **End-of-body re-registration used the SOURCE class name while the body was compiled under the RENAMED one.** When a function-nested class collides with another declaration (`class_renames` in play), the end-of-body capture re-registration ran after the rename map was restored, so it registered under the wrong name and the refresh never reached the renamed class's id. Re-registration now happens before the `class_renames` restore and goes through `resolve_class_name`. (`crates/perry-hir/src/lower_decl/block.rs`, `crates/perry-hir/src/lower/expr_function.rs`)
+2. **The snapshot only refreshed before `return` statements — a captured local ASSIGNED after the class decl in the same body kept its stale decl-time value.** `insert_class_capture_refresh_after_assignments` now re-snapshots after every top-level assignment/update of a captured local that follows the class declaration in the same body (companion to the existing before-returns refresh).
+
+Salvages the stranded `issue_5437_incremental_cache_get_chain` e2e from the probe branch and adds `capture_rereg_renamed_class` (4 tests). Verified: parity vs the 2026-07-03 baseline shows 0 real newly-failing (one fs-fd flake ruled out by 6/6 local matches) and 6 newly-passing.
+
 ## v0.5.1229 — write-path hardening slice 2: transition_fast tags, structuredClone band, rejection printer (#5948)
 
 Continuation of #5943 (2026-07-02 audit §6). js_object_set_field_by_name_transition_fast — the first thing every generic `obj.field = v` hits until any defineProperty runs — admitted SSO strings/tag remnants via a `top16 >= 0x7FF8` catch-all then deref'd a bare GcHeader floor (a 2–5-char SSO payload lands in the 2–5.5TB range and passes the macOS heap floor — the write-side #5429 twin); now POINTER-tag-only, full handle band, try_read_gc_header, with return-0 deferring to the full dynamic path. structuredClone deref'd any POINTER payload ≥0x10000 as GcHeader bytes after the registry probes (fetch/zlib registry ids crashed); full-band gate + validated header probe, pass-through unchanged for non-probeables. The unhandled-rejection printer deref'd POINTER-tagged reasons with a bare ≥0x10000 (a thrown fetch Response id crashed instead of printing); is_plausible_heap_addr gate. e2e: write_path_band_slice2.rs.
diff --git a/CLAUDE.md b/CLAUDE.md
index a9f8181a85..9810e0ce2c 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:** 0.5.1229
+**Current Version:** 0.5.1230
 
 
 ## TypeScript Parity Status
diff --git a/Cargo.lock b/Cargo.lock
index 6b47ad6f5e..45dc2198f4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5338,7 +5338,7 @@ checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
 [[package]]
 name = "perry"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "base64",
@@ -5395,14 +5395,14 @@ dependencies = [
 
 [[package]]
 name = "perry-api-manifest"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "serde",
 ]
 
 [[package]]
 name = "perry-audio-miniaudio"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "cc",
  "libc",
@@ -5410,7 +5410,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "log",
@@ -5425,7 +5425,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-arkts"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5434,7 +5434,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-glance"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5442,7 +5442,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-js"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-dispatch",
@@ -5452,7 +5452,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-swiftui"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5461,7 +5461,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wasm"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "base64",
@@ -5474,7 +5474,7 @@ dependencies = [
 
 [[package]]
 name = "perry-codegen-wear-tiles"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -5482,7 +5482,7 @@ dependencies = [
 
 [[package]]
 name = "perry-container-compose"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -5511,14 +5511,14 @@ dependencies = [
 
 [[package]]
 name = "perry-container-e2e"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
 ]
 
 [[package]]
 name = "perry-diagnostics"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "serde",
  "serde_json",
@@ -5526,7 +5526,7 @@ dependencies = [
 
 [[package]]
 name = "perry-dispatch"
-version = "0.5.1229"
+version = "0.5.1230"
 
 [[package]]
 name = "perry-doc-fixture-my-bindings"
@@ -5537,7 +5537,7 @@ dependencies = [
 
 [[package]]
 name = "perry-doc-tests"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "clap",
@@ -5552,7 +5552,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ads"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "block2",
  "objc2",
@@ -5562,7 +5562,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-argon2"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "argon2",
  "perry-ffi",
@@ -5570,7 +5570,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-axios"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "reqwest",
@@ -5579,7 +5579,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-bcrypt"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bcrypt",
  "perry-ffi",
@@ -5587,7 +5587,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-better-sqlite3"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "rusqlite",
@@ -5595,7 +5595,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cheerio"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "scraper",
@@ -5603,7 +5603,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-commander"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5611,7 +5611,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-cron"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "chrono",
  "cron",
@@ -5621,7 +5621,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dayjs"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5629,7 +5629,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-decimal"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "rust_decimal",
@@ -5637,7 +5637,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-dotenv"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "serde_json",
@@ -5645,7 +5645,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ethers"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "rand 0.8.6",
@@ -5653,7 +5653,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-events"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "perry-runtime",
@@ -5661,14 +5661,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-exponential-backoff"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-fastify"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bytes",
  "http-body-util",
@@ -5686,7 +5686,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-fetch"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bytes",
  "lazy_static",
@@ -5699,7 +5699,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-http"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bytes",
  "lazy_static",
@@ -5713,7 +5713,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-http-server"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bytes",
  "h2",
@@ -5736,7 +5736,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ioredis"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -5746,7 +5746,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-jsonwebtoken"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "jsonwebtoken",
@@ -5757,7 +5757,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-lru-cache"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "lru",
  "perry-ffi",
@@ -5765,7 +5765,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-moment"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5773,7 +5773,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mongodb"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bson",
  "futures-util",
@@ -5785,7 +5785,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-mysql2"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "chrono",
  "perry-ffi",
@@ -5795,7 +5795,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nanoid"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "nanoid",
  "perry-ffi",
@@ -5804,7 +5804,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-net"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "bytes",
  "perry-ffi",
@@ -5817,7 +5817,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-nodemailer"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "lettre",
  "perry-ffi",
@@ -5827,7 +5827,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pdf"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "printpdf",
@@ -5835,7 +5835,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-pg"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "sqlx",
@@ -5844,7 +5844,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ratelimit"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "governor",
  "perry-ffi",
@@ -5852,7 +5852,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-sharp"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "fast_image_resize",
  "image",
@@ -5862,14 +5862,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-slugify"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
 ]
 
 [[package]]
 name = "perry-ext-streams"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "lazy_static",
  "perry-ffi",
@@ -5878,7 +5878,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-uuid"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "uuid",
@@ -5886,7 +5886,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-validator"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ffi",
  "regex",
@@ -5896,7 +5896,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-ws"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "futures-util",
  "lazy_static",
@@ -5908,7 +5908,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ext-zlib"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "brotli",
  "flate2",
@@ -5917,7 +5917,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ffi"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "dashmap",
  "once_cell",
@@ -5926,7 +5926,7 @@ dependencies = [
 
 [[package]]
 name = "perry-hir"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-api-manifest",
@@ -5944,7 +5944,7 @@ dependencies = [
 
 [[package]]
 name = "perry-parser"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-diagnostics",
@@ -5956,7 +5956,7 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "base64",
@@ -5989,14 +5989,14 @@ dependencies = [
 
 [[package]]
 name = "perry-runtime-static"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-runtime",
 ]
 
 [[package]]
 name = "perry-stdlib"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "aes 0.8.4",
  "aes-gcm",
@@ -6089,14 +6089,14 @@ dependencies = [
 
 [[package]]
 name = "perry-stdlib-static"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-stdlib",
 ]
 
 [[package]]
 name = "perry-transform"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "perry-hir",
@@ -6106,7 +6106,7 @@ dependencies = [
 
 [[package]]
 name = "perry-types"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "anyhow",
  "thiserror 1.0.69",
@@ -6114,14 +6114,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ui-model",
 ]
 
 [[package]]
 name = "perry-ui-android"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "itoa",
@@ -6138,7 +6138,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-geisterhand"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "rand 0.8.6",
  "serde",
@@ -6148,7 +6148,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-gtk4"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "cairo-rs 0.22.0",
@@ -6171,7 +6171,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-ios"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "block2",
@@ -6187,7 +6187,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-macos"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "block2",
@@ -6202,7 +6202,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-model"
-version = "0.5.1229"
+version = "0.5.1230"
 
 [[package]]
 name = "perry-ui-test"
@@ -6210,11 +6210,11 @@ version = "0.1.0"
 
 [[package]]
 name = "perry-ui-testkit"
-version = "0.5.1229"
+version = "0.5.1230"
 
 [[package]]
 name = "perry-ui-tvos"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "block2",
@@ -6230,7 +6230,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-visionos"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "block2",
@@ -6246,7 +6246,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-watchos"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "block2",
  "libc",
@@ -6259,7 +6259,7 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "libc",
@@ -6276,14 +6276,14 @@ dependencies = [
 
 [[package]]
 name = "perry-ui-windows-winui"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "perry-ui-windows",
 ]
 
 [[package]]
 name = "perry-updater"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "base64",
  "ed25519-dalek",
@@ -6297,7 +6297,7 @@ dependencies = [
 
 [[package]]
 name = "perry-wasm-host"
-version = "0.5.1229"
+version = "0.5.1230"
 dependencies = [
  "wasmi",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 49ef952f28..bc7126a756 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -301,7 +301,7 @@ strip = false
 codegen-units = 16
 
 [workspace.package]
-version = "0.5.1229"
+version = "0.5.1230"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/PerryTS/perry"
diff --git a/crates/perry-hir/src/lower/expr_function.rs b/crates/perry-hir/src/lower/expr_function.rs
index 55cf433c4c..e69f4993cb 100644
--- a/crates/perry-hir/src/lower/expr_function.rs
+++ b/crates/perry-hir/src/lower/expr_function.rs
@@ -1144,6 +1144,7 @@ fn lower_fn_expr_anon(ctx: &mut LoweringContext, fn_expr: &ast::FnExpr) -> Resul
     // trailing `return`).
     if let Some(ref block) = fn_expr.function.body {
         let mut re_regs: Vec<Stmt> = Vec::new();
+        let mut re_reg_capsets: Vec<(Stmt, std::collections::HashSet<LocalId>)> = Vec::new();
         for stmt in &block.stmts {
             if let ast::Stmt::Decl(ast::Decl::Class(class_decl)) = stmt {
                 // A colliding `class X` may have been renamed during body
@@ -1159,15 +1160,21 @@ fn lower_fn_expr_anon(ctx: &mut LoweringContext, fn_expr: &ast::FnExpr) -> Resul
                         for s in body.iter_mut() {
                             crate::lower_decl::append_new_args_stmt(s, &cname, &cap_args, true);
                         }
-                        re_regs.push(Stmt::Expr(Expr::RegisterClassCaptures {
+                        let re_reg = Stmt::Expr(Expr::RegisterClassCaptures {
                             class_name: cname,
                             captures,
-                        }));
+                        });
+                        re_reg_capsets.push((re_reg.clone(), captured.iter().copied().collect()));
+                        re_regs.push(re_reg);
                     }
                 }
             }
         }
         if !re_regs.is_empty() {
+            // Audit P0-B twin of the block-body path: refresh after every
+            // same-body assignment to a captured local so mid-body constructs
+            // read the live value through the authoritative snapshot.
+            insert_class_capture_refresh_after_assignments(&mut body, &re_reg_capsets);
             // Refresh the snapshot before EVERY reachable `return` in the body
             // (not only a trailing one): an EARLY `return <class>` after the
             // captured locals are assigned would otherwise return a class with
@@ -1262,7 +1269,7 @@ fn lower_fn_expr_anon(ctx: &mut LoweringContext, fn_expr: &ast::FnExpr) -> Resul
 /// — a closure's `return` exits a different function and must keep its own
 /// snapshot. Each return path then records the live capture values at that
 /// point. See the call site in `lower_fn_expr_anon` (CodeRabbit #5739).
-fn insert_class_capture_refresh_before_returns(stmts: &mut Vec<Stmt>, re_regs: &[Stmt]) {
+pub(crate) fn insert_class_capture_refresh_before_returns(stmts: &mut Vec<Stmt>, re_regs: &[Stmt]) {
     let mut i = 0;
     while i < stmts.len() {
         insert_class_capture_refresh_into_stmt(&mut stmts[i], re_regs);
@@ -1399,3 +1406,88 @@ fn compute_closure_captures(
 
     (captures, mutable_captures)
 }
+
+/// Insert a class-capture refresh immediately AFTER every statement that
+/// assigns one of the class's captured locals (2026-07-02 audit capture
+/// P0-B). The decl-site snapshot is AUTHORITATIVE at construct time (the
+/// appended cap arg can be a mis-boxed multi-level capture — the W6 class),
+/// so a same-body assignment after the class declaration must update the
+/// snapshot or every later construct reads the stale decl-time value and
+/// `emit_class_capture_writeback` then resets the outer local to it:
+///
+///   let x = 1;
+///   class C { m() { return x; } }
+///   x = 2;                    // ← refresh inserted after this statement
+///   new C().m()               // reads 2 (was: 1, and x reset to 1)
+///
+/// Descends into nested statement bodies (assignments inside if/loop arms
+/// get their refresh at that level) but not into closures — a closure's
+/// assignment happens at ITS call time, not lexically here. Refreshes
+/// inserted before the class's own declaration are harmless: the decl-site
+/// registration overwrites them in program order.
+pub(crate) fn insert_class_capture_refresh_after_assignments(
+    stmts: &mut Vec<Stmt>,
+    regs: &[(Stmt, std::collections::HashSet<perry_types::LocalId>)],
+) {
+    let mut i = 0;
+    while i < stmts.len() {
+        // Recurse first so nested bodies get their own refreshes.
+        match &mut stmts[i] {
+            Stmt::If {
+                then_branch,
+                else_branch,
+                ..
+            } => {
+                insert_class_capture_refresh_after_assignments(then_branch, regs);
+                if let Some(eb) = else_branch {
+                    insert_class_capture_refresh_after_assignments(eb, regs);
+                }
+            }
+            Stmt::While { body, .. } | Stmt::DoWhile { body, .. } => {
+                insert_class_capture_refresh_after_assignments(body, regs);
+            }
+            Stmt::For { body, .. } => {
+                insert_class_capture_refresh_after_assignments(body, regs);
+            }
+            Stmt::Try {
+                body,
+                catch,
+                finally,
+            } => {
+                insert_class_capture_refresh_after_assignments(body, regs);
+                if let Some(c) = catch {
+                    insert_class_capture_refresh_after_assignments(&mut c.body, regs);
+                }
+                if let Some(f) = finally {
+                    insert_class_capture_refresh_after_assignments(f, regs);
+                }
+            }
+            Stmt::Switch { cases, .. } => {
+                for case in cases.iter_mut() {
+                    insert_class_capture_refresh_after_assignments(&mut case.body, regs);
+                }
+            }
+            _ => {}
+        }
+        // Does this statement (at THIS level, closures excluded by the
+        // collector) assign any watched capture?
+        let mut assigned = Vec::new();
+        collect_assigned_locals_stmt(&stmts[i], &mut assigned);
+        if !assigned.is_empty() {
+            let mut inserts: Vec<Stmt> = Vec::new();
+            for (re_reg, capset) in regs {
+                if matches!(&stmts[i], Stmt::Expr(Expr::RegisterClassCaptures { .. })) {
+                    continue;
+                }
+                if assigned.iter().any(|id| capset.contains(id)) {
+                    inserts.push(re_reg.clone());
+                }
+            }
+            for (j, s) in inserts.iter().cloned().enumerate() {
+                stmts.insert(i + 1 + j, s);
+            }
+            i += inserts.len();
+        }
+        i += 1;
+    }
+}
diff --git a/crates/perry-hir/src/lower/mod.rs b/crates/perry-hir/src/lower/mod.rs
index 8eeef1c9d3..583aefaca3 100644
--- a/crates/perry-hir/src/lower/mod.rs
+++ b/crates/perry-hir/src/lower/mod.rs
@@ -37,7 +37,7 @@
 mod context;
 pub(crate) mod expr_assign;
 mod expr_call;
-mod expr_function;
+pub(crate) mod expr_function;
 pub(crate) use expr_function::capture_function_source;
 mod expr_member;
 pub(crate) use expr_member::{wrap_private_guard, PRIV_OP_WRITE};
diff --git a/crates/perry-hir/src/lower_decl/block.rs b/crates/perry-hir/src/lower_decl/block.rs
index 2e200c18f1..05178b391e 100644
--- a/crates/perry-hir/src/lower_decl/block.rs
+++ b/crates/perry-hir/src/lower_decl/block.rs
@@ -1025,23 +1025,30 @@ pub fn lower_fn_body_block_stmt(
             return Err(err);
         }
     };
-    ctx.forward_class_names = saved_forward_class_names;
-    ctx.forward_class_decl_depth = saved_forward_class_decl_depth;
-    ctx.class_renames = saved_class_renames;
-
     // Re-register capture snapshots for classes declared in this body at
     // its END. The decl-site `RegisterClassCaptures` runs before later
     // statements assign captured vars (tsc emits TS-enum namespaces AFTER
     // the classes that reference them — vendored zod's
     // ZodFirstPartyTypeKind), so static-method snapshot reads and post-
-    // return dynamic constructions need the FINAL values. Inserted before
-    // a trailing `return` when present; bodies with early returns keep the
-    // decl-site snapshot for those paths.
+    // return dynamic constructions need the FINAL values.
+    //
+    // MUST run while this body's `class_renames` are still ACTIVE, using the
+    // RESOLVED class name (2026-07-02 audit P0): with the restore-first +
+    // raw-ident order, factory B's renamed `class e` (→ `e$0`) re-registered
+    // the OUTER factory's `e` with B's out-of-scope ids — codegen's LocalGet
+    // soft-fallback then clobbered A's snapshot to all-undefined the moment
+    // B ran, resurrecting the W6 undefined-captures class for every dynamic
+    // construct of A's class; meanwhile `e$0` itself never got refreshed and
+    // its forward-ref `new` sites never got their cap args appended.
+    // Mirrors the function-expression twin (`lower_fn_expr`), including the
+    // refresh-before-EVERY-return placement.
     {
         let mut re_regs: Vec<Stmt> = Vec::new();
+        let mut re_reg_capsets: Vec<(Stmt, std::collections::HashSet<perry_types::LocalId>)> =
+            Vec::new();
         for stmt in &block.stmts {
             if let ast::Stmt::Decl(ast::Decl::Class(class_decl)) = stmt {
-                let cname = class_decl.ident.sym.to_string();
+                let cname = ctx.resolve_class_name(class_decl.ident.sym.as_str());
                 if let Some(captured) = ctx.lookup_class_captures(&cname) {
                     if !captured.is_empty() {
                         let captures: Vec<Expr> =
@@ -1065,25 +1072,34 @@ pub fn lower_fn_body_block_stmt(
                         for s in body.iter_mut() {
                             super::class_captures::append_new_args_stmt(s, &cname, &cap_args, true);
                         }
-                        re_regs.push(Stmt::Expr(Expr::RegisterClassCaptures {
+                        let re_reg = Stmt::Expr(Expr::RegisterClassCaptures {
                             class_name: cname,
                             captures,
-                        }));
+                        });
+                        re_reg_capsets.push((re_reg.clone(), captured.iter().copied().collect()));
+                        re_regs.push(re_reg);
                     }
                 }
             }
         }
         if !re_regs.is_empty() {
-            let insert_at = if matches!(body.last(), Some(Stmt::Return(_))) {
-                body.len() - 1
-            } else {
-                body.len()
-            };
-            for (i, s) in re_regs.into_iter().enumerate() {
-                body.insert(insert_at + i, s);
-            }
+            // Audit P0-B: the decl-site snapshot is authoritative at
+            // construct time, so keep it TRACKING same-body assignments —
+            // refresh after every statement that assigns a captured local
+            // (else `let x=1; class C{..x..}; x=2; new C()` reads 1 and the
+            // capture write-back resets x to 1).
+            crate::lower::expr_function::insert_class_capture_refresh_after_assignments(
+                &mut body,
+                &re_reg_capsets,
+            );
+            crate::lower::expr_function::insert_class_capture_refresh_before_returns(
+                &mut body, &re_regs,
+            );
         }
     }
+    ctx.forward_class_names = saved_forward_class_names;
+    ctx.forward_class_decl_depth = saved_forward_class_decl_depth;
+    ctx.class_renames = saved_class_renames;
 
     // Undefined-initialised entry slots for hoisted `var`s declared in
     // nested blocks (see predefine_var_bindings_in_function_body docs).
diff --git a/crates/perry/tests/capture_rereg_renamed_class.rs b/crates/perry/tests/capture_rereg_renamed_class.rs
new file mode 100644
index 0000000000..ee1c30d22c
--- /dev/null
+++ b/crates/perry/tests/capture_rereg_renamed_class.rs
@@ -0,0 +1,178 @@
+//! Regression tests for the 2026-07-02 audit's capture-re-registration P0:
+//! the end-of-body `RegisterClassCaptures` refresh in arrow/function-decl
+//! bodies (a) ran AFTER `ctx.class_renames` was restored and looked the
+//! class up by its RAW ident, and (b) inserted only before a TRAILING
+//! return.
+//!
+//! (a) meant factory B's `class e` (renamed `e$0` when factory A's `class e`
+//! was lowered first) re-registered factory A's `e` with B's out-of-scope
+//! ids — codegen's LocalGet soft-fallback then clobbered A's snapshot to
+//! all-undefined the moment B ran (minified bundles reuse one-letter class
+//! names across hundreds of factories, so both preconditions were
+//! near-certain at bundle scale); `e$0` itself never got refreshed. (b)
+//! meant early-return paths kept the stale decl-site snapshot.
+//!
+//! Static-method reads go through the snapshot-only prologue, so they
+//! discriminate the snapshot's value directly. Expected outputs are
+//! byte-for-byte `node --experimental-strip-types`.
+
+use std::path::PathBuf;
+use std::process::Command;
+
+fn perry_bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_perry"))
+}
+
+fn compile_and_run(dir: &std::path::Path, source: &str) -> String {
+    let entry = dir.join("main.ts");
+    let output = dir.join("main_bin");
+    std::fs::write(&entry, source).expect("write entry");
+
+    let compile = Command::new(perry_bin())
+        .current_dir(dir)
+        .arg("compile")
+        .arg(&entry)
+        .arg("-o")
+        .arg(&output)
+        .arg("--no-cache")
+        .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)
+        .output()
+        .expect("run compiled binary");
+    assert!(
+        run.status.success(),
+        "compiled binary failed (exit {:?})\nstdout:\n{}\nstderr:\n{}",
+        run.status.code(),
+        String::from_utf8_lossy(&run.stdout),
+        String::from_utf8_lossy(&run.stderr)
+    );
+    String::from_utf8_lossy(&run.stdout).into_owned()
+}
+
+/// Two arrow factories each declaring `class e` with their own captures:
+/// running factory B must not clobber factory A's capture snapshot (A's
+/// static read still sees "alpha" after B ran).
+#[test]
+fn same_class_name_across_factories_keeps_snapshots_separate() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let stdout = compile_and_run(
+        dir.path(),
+        r#"
+const makeA = () => {
+  const tagA = "alpha";
+  class e {
+    static who() {
+      return tagA;
+    }
+  }
+  return () => e.who();
+};
+const whoA = makeA();
+const makeB = (x: number) => {
+  const tagB = "beta" + x;
+  class e {
+    static who() {
+      return tagB;
+    }
+  }
+  return e.who();
+};
+console.log("A1:", whoA());
+console.log("B:", makeB(1));
+console.log("A2:", whoA());
+"#,
+    );
+    assert_eq!(stdout, "A1: alpha\nB: beta1\nA2: alpha\n");
+}
+
+/// The snapshot refresh must run before EVERY return, not only a trailing
+/// one: an early return after a captured-var mutation must see the mutated
+/// value in the snapshot (static reads are snapshot-only).
+#[test]
+fn snapshot_refresh_covers_early_returns() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let stdout = compile_and_run(
+        dir.path(),
+        r#"
+function makeC(flag: boolean) {
+  let n = 1;
+  class e {
+    static val() {
+      return n;
+    }
+  }
+  n = 2;
+  if (flag) return e.val;
+  n = 3;
+  return e.val;
+}
+console.log("C-early:", makeC(true)());
+console.log("C-late:", makeC(false)());
+"#,
+    );
+    assert_eq!(stdout, "C-early: 2\nC-late: 3\n");
+}
+
+/// Audit P0-B: a same-body assignment AFTER the class declaration must be
+/// visible to a mid-body construct (the decl-site snapshot is authoritative
+/// at construct time, so it must track assignments), and the capture
+/// write-back must not reset the outer local to the stale value.
+#[test]
+fn mid_body_construct_sees_assignment_after_class_decl() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let stdout = compile_and_run(
+        dir.path(),
+        r#"
+function f() {
+  let x = 1;
+  class C {
+    m() {
+      return x;
+    }
+  }
+  x = 2;
+  const c = new C();
+  console.log("m:", c.m(), "x:", x);
+}
+f();
+"#,
+    );
+    assert_eq!(stdout, "m: 2 x: 2\n");
+}
+
+/// Assignment inside an if-branch after the declaration (the zod
+/// enum-namespace-after-class shape): static reads are snapshot-only, so
+/// the branch's refresh must land at its own nesting level.
+#[test]
+fn branch_assignment_refreshes_snapshot() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let stdout = compile_and_run(
+        dir.path(),
+        r#"
+function g(flag: boolean) {
+  let cfg: any = null;
+  class D {
+    static read() {
+      return cfg === null ? "null" : cfg.mode;
+    }
+  }
+  if (flag) {
+    cfg = { mode: "live" };
+  }
+  console.log("D:", D.read());
+}
+g(true);
+g(false);
+"#,
+    );
+    assert_eq!(stdout, "D: live\nD: null\n");
+}
diff --git a/crates/perry/tests/issue_5437_incremental_cache_get_chain.rs b/crates/perry/tests/issue_5437_incremental_cache_get_chain.rs
new file mode 100644
index 0000000000..9958a84e46
--- /dev/null
+++ b/crates/perry/tests/issue_5437_incremental_cache_get_chain.rs
@@ -0,0 +1,128 @@
+//! Regression test for #5437 (Next.js `context.incrementalCache.get(...)` wall).
+//!
+//! This is the end-to-end shape that the per-implementor-arity dispatch fix
+//! (#5622, `crates/perry-codegen/src/lower_call/property_get.rs`) unblocks. Two
+//! walls lived on this exact chain in the Next.js app-router render:
+//!
+//!   1. `Cannot read properties of undefined (reading 'get')` — the 3rd
+//!      positional arg `context` of `responseCache.get(key, gen, context)` was
+//!      collapsed to `0.0` because `get` has a `...rest` implementor and the
+//!      dispatch tower applied ONE global rest-bundle to every case, dropping
+//!      the non-rest 3-arg implementor's positional params. `const {
+//!      incrementalCache } = context` then destructured off `0.0`.
+//!
+//!   2. `get is not a function` — once `context` survives, the chained
+//!      `context.incrementalCache.get(key, { kind })` must itself resolve
+//!      through the (multi-implementor) dispatch tower. If the tower mis-routes
+//!      or the receiver's class-id misses every case, it falls through to
+//!      `js_native_call_method`'s catch-all and throws the bare
+//!      `get is not a function`.
+//!
+//! With the per-implementor-arity fix both walls are gone: `context` arrives
+//! intact AND the chained async `incrementalCache.get` dispatches to the right
+//! 2-arg method. This test models the chain (object-literal 3rd arg carrying an
+//! IncrementalCache instance; `get` co-implemented by a `...rest` class and a
+//! 1-arg class so the tower has multiple cases) and asserts the same byte
+//! output as `node --experimental-strip-types`.
+
+use std::path::PathBuf;
+use std::process::Command;
+
+fn perry_bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_perry"))
+}
+
+fn compile_and_run(dir: &std::path::Path, source: &str) -> String {
+    let entry = dir.join("main.ts");
+    let output = dir.join("main_bin");
+    std::fs::write(&entry, source).expect("write entry");
+
+    let compile = Command::new(perry_bin())
+        .current_dir(dir)
+        .arg("compile")
+        .arg(&entry)
+        .arg("-o")
+        .arg(&output)
+        .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)
+        .output()
+        .expect("run compiled binary");
+    assert!(
+        run.status.success(),
+        "compiled binary failed\nstatus: {:?}\nstdout:\n{}\nstderr:\n{}",
+        run.status,
+        String::from_utf8_lossy(&run.stdout),
+        String::from_utf8_lossy(&run.stderr)
+    );
+    String::from_utf8_lossy(&run.stdout).into_owned()
+}
+
+/// The 3rd positional arg of an untyped `f.get(key, gen, context)` call is an
+/// object literal carrying an `IncrementalCache` instance. `f.get` (the
+/// non-rest 3-arg `ResponseCache.get`) must receive `context` intact, destructure
+/// `incrementalCache` off it, and the chained async `incrementalCache.get(key,
+/// { kind })` must dispatch to the 2-arg method WITHOUT "get is not a function" —
+/// even though `get` is also implemented by a `...rest` class and a 1-arg class.
+#[test]
+fn incremental_cache_get_chain_resolves() {
+    let dir = tempfile::tempdir().expect("tempdir");
+    let stdout = compile_and_run(
+        dir.path(),
+        r#"
+class IncrementalCache {
+  async get(cacheKey: string, ctx: { kind: string }): Promise<string> {
+    return "IC.get(" + cacheKey + "," + ctx.kind + ")";
+  }
+}
+
+// Sibling `get` implementors with differing arity, including a ...rest one, so
+// the dynamic-dispatch tower has multiple cases (the shape that made the
+// rest-bundle collapse every case pre-#5622).
+class WithRest {
+  get(...r: any[]): string { return "rest:" + r.length; }
+}
+class OneArg {
+  get(a: any): string { return "one:" + String(a); }
+}
+
+class ResponseCache {
+  // 3-arg async method; 3rd param `context` MUST survive dispatch (pre-#5622 it
+  // read 0.0 → `const { incrementalCache } = context` off a number).
+  async get(key: string, gen: number, context: any): Promise<string> {
+    const { incrementalCache } = context;
+    const r = await incrementalCache.get(key, { kind: "APP" });
+    return "handleGet[" + r + "]";
+  }
+}
+
+function pickGetter(n: number): any {
+  if (n === 0) return new WithRest();
+  if (n === 1) return new ResponseCache();
+  return new OneArg();
+}
+
+async function main() {
+  const f: any = pickGetter(1);
+  const ic: any = new IncrementalCache();
+  // 3rd positional arg = object literal carrying the IncrementalCache instance.
+  const out = await f.get("k1", 7, { routeKind: "APP", incrementalCache: ic, waitUntil: null });
+  console.log(out);
+  // Exercise the rest + one-arg siblings so the tower keeps >1 implementor.
+  console.log(pickGetter(0).get(1, 2, 3));
+  console.log(pickGetter(2).get(9, 9, 9));
+}
+main();
+"#,
+    );
+    // node --experimental-strip-types prints exactly this.
+    assert_eq!(stdout, "handleGet[IC.get(k1,APP)]\nrest:3\none:9\n");
+}