diff --git a/Cargo.lock b/Cargo.lock
index 13dbb7e3..1ec1c042 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -13,6 +13,21 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "addr2line"
+version = "0.25.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1b5d307320b3181d6d7954e663bd7c774a838b8220fe0593c86d9fb09f498b4b"
+dependencies = [
+ "gimli",
+]
+
+[[package]]
+name = "adler2"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
+
 [[package]]
 name = "aead"
 version = "0.5.2"
@@ -55,6 +70,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5a15f179cd60c4584b8a8c596927aadc462e27f2ca70c04e0071964a73ba7a75"
 dependencies = [
  "cfg-if 1.0.4",
+ "getrandom 0.3.4",
  "once_cell",
  "version_check",
  "zerocopy",
@@ -656,6 +672,21 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "backtrace"
+version = "0.3.76"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bb531853791a215d7c62a30daf0dde835f381ab5de4589cfe7c649d2cbe92bd6"
+dependencies = [
+ "addr2line",
+ "cfg-if 1.0.4",
+ "libc",
+ "miniz_oxide",
+ "object",
+ "rustc-demangle",
+ "windows-link",
+]
+
 [[package]]
 name = "base-x"
 version = "0.2.11"
@@ -1835,6 +1866,25 @@ dependencies = [
  "syn 2.0.111",
 ]
 
+[[package]]
+name = "env_filter"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7a1c3cc8e57274ec99de65301228b537f1e4eedc1b8e0f9411c6caac8ae7308f"
+dependencies = [
+ "log",
+]
+
+[[package]]
+name = "env_logger"
+version = "0.11.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2daee4ea451f429a58296525ddf28b45a3b64f1acf6587e2067437bb11e218d"
+dependencies = [
+ "env_filter",
+ "log",
+]
+
 [[package]]
 name = "equivalent"
 version = "1.0.2"
@@ -1953,6 +2003,7 @@ dependencies = [
  "spawned-concurrency",
  "spawned-rt",
  "thiserror 2.0.17",
+ "tikv-jemallocator",
  "tokio",
  "tracing",
  "tracing-subscriber",
@@ -2048,6 +2099,7 @@ dependencies = [
  "ethlambda-storage",
  "ethlambda-types",
  "http-body-util",
+ "jemalloc_pprof",
  "serde",
  "serde_json",
  "tokio",
@@ -2482,6 +2534,16 @@ dependencies = [
  "static_assertions",
 ]
 
+[[package]]
+name = "flate2"
+version = "1.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "843fba2746e448b37e26a819579957415c8cef339bf08564fe8b7ddbd959573c"
+dependencies = [
+ "crc32fast",
+ "miniz_oxide",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -2711,6 +2773,12 @@ dependencies = [
  "polyval",
 ]
 
+[[package]]
+name = "gimli"
+version = "0.32.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e629b9b98ef3dd8afe6ca2bd0f89306cec16d43d907889945bc5d6687f2f13c7"
+
 [[package]]
 name = "git2"
 version = "0.20.3"
@@ -3250,6 +3318,28 @@ dependencies = [
  "serde_core",
 ]
 
+[[package]]
+name = "inferno"
+version = "0.12.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90807d610575744524d9bdc69f3885d96f0e6c3354565b0828354a7ff2a262b8"
+dependencies = [
+ "ahash",
+ "clap",
+ "crossbeam-channel 0.5.15",
+ "crossbeam-utils 0.8.21",
+ "dashmap",
+ "env_logger",
+ "indexmap",
+ "itoa",
+ "log",
+ "num-format",
+ "once_cell",
+ "quick-xml",
+ "rgb",
+ "str_stack",
+]
+
 [[package]]
 name = "inout"
 version = "0.1.4"
@@ -3335,6 +3425,23 @@ version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4a5f13b858c8d314ee3e8f639011f7ccefe71f97f96e50151fb991f267928e2c"
 
+[[package]]
+name = "jemalloc_pprof"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a0d44c349cfe2654897fadcb9de4f0bfbf48288ec344f700b2bd59f152dd209"
+dependencies = [
+ "anyhow",
+ "libc",
+ "mappings",
+ "once_cell",
+ "pprof_util",
+ "tempfile",
+ "tikv-jemalloc-ctl",
+ "tokio",
+ "tracing",
+]
+
 [[package]]
 name = "jobserver"
 version = "0.1.34"
@@ -4397,6 +4504,19 @@ dependencies = [
  "malachite-nz",
 ]
 
+[[package]]
+name = "mappings"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8bab1e61a4b76757edb59cd81fcaa7f3ba9018d43b527d9abfad877b4c6c60f2"
+dependencies = [
+ "anyhow",
+ "libc",
+ "once_cell",
+ "pprof_util",
+ "tracing",
+]
+
 [[package]]
 name = "match-lookup"
 version = "0.1.2"
@@ -4466,6 +4586,16 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
 
+[[package]]
+name = "miniz_oxide"
+version = "0.8.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fa76a2c86f704bdb222d66965fb3d63269ce38518b83cb0575fca855ebb6316"
+dependencies = [
+ "adler2",
+ "simd-adler32",
+]
+
 [[package]]
 name = "mio"
 version = "1.1.1"
@@ -4694,6 +4824,20 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "num"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35bd024e8b2ff75562e5f34e7f4905839deb4b22955ef5e73d2fea1b9813cb23"
+dependencies = [
+ "num-bigint 0.4.6",
+ "num-complex",
+ "num-integer",
+ "num-iter",
+ "num-rational",
+ "num-traits",
+]
+
 [[package]]
 name = "num-bigint"
 version = "0.3.3"
@@ -4715,12 +4859,31 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "num-complex"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73f88a1307638156682bada9d7604135552957b7818057dcef22705b4d509495"
+dependencies = [
+ "num-traits",
+]
+
 [[package]]
 name = "num-conv"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51d515d32fb182ee37cda2ccdcb92950d6a3c2893aa280e540671c2cd0f3b1d9"
 
+[[package]]
+name = "num-format"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a652d9771a63711fd3c3deb670acfbe5c30a4072e664d7a3bf5a9e1056ac72c3"
+dependencies = [
+ "arrayvec",
+ "itoa",
+]
+
 [[package]]
 name = "num-integer"
 version = "0.1.46"
@@ -4730,6 +4893,28 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "num-iter"
+version = "0.1.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1429034a0490724d0075ebb2bc9e875d6503c3cf69e235a8941aa757d83ef5bf"
+dependencies = [
+ "autocfg",
+ "num-integer",
+ "num-traits",
+]
+
+[[package]]
+name = "num-rational"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f83d14da390562dca69fc84082e73e548e1ad308d24accdedd2720017cb37824"
+dependencies = [
+ "num-bigint 0.4.6",
+ "num-integer",
+ "num-traits",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.19"
@@ -4781,6 +4966,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "object"
+version = "0.37.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ff76201f031d8863c38aa7f905eca4f53abbfa15f609db4277d44cd8938f33fe"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "oid-registry"
 version = "0.8.1"
@@ -5535,6 +5729,21 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "439ee305def115ba05938db6eb1644ff94165c5ab5e9420d1c1bcedbba909391"
 
+[[package]]
+name = "pprof_util"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eea0cc524de808a6d98d192a3d99fe95617031ad4a52ec0a0f987ef4432e8fe1"
+dependencies = [
+ "anyhow",
+ "backtrace",
+ "flate2",
+ "inferno",
+ "num",
+ "paste",
+ "prost",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.21"
@@ -5652,6 +5861,29 @@ dependencies = [
  "unarray",
 ]
 
+[[package]]
+name = "prost"
+version = "0.14.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2ea70524a2f82d518bce41317d0fae74151505651af45faf1ffbd6fd33f0568"
+dependencies = [
+ "bytes",
+ "prost-derive",
+]
+
+[[package]]
+name = "prost-derive"
+version = "0.14.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "27c6023962132f4b30eb4c172c91ce92d933da334c59c23cddee82358ddafb0b"
+dependencies = [
+ "anyhow",
+ "itertools 0.14.0",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.111",
+]
+
 [[package]]
 name = "protobuf"
 version = "3.7.2"
@@ -5728,6 +5960,15 @@ dependencies = [
  "unsigned-varint",
 ]
 
+[[package]]
+name = "quick-xml"
+version = "0.39.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "958f21e8e7ceb5a1aa7fa87fab28e7c75976e0bfe7e23ff069e0a260f894067d"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "quinn"
 version = "0.11.9"
@@ -6088,6 +6329,15 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "rgb"
+version = "0.8.53"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47b34b781b31e5d73e9fbc8689c70551fd1ade9a19e3e28cfec8580a79290cc4"
+dependencies = [
+ "bytemuck",
+]
+
 [[package]]
 name = "ring"
 version = "0.17.14"
@@ -6223,6 +6473,12 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "48fd7bd8a6377e15ad9d42a8ec25371b94ddc67abe7c8b9127bec79bebaaae18"
 
+[[package]]
+name = "rustc-demangle"
+version = "0.1.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b50b8869d9fc858ce7266cce0194bd74df58b9d0e3f6df3a9fc8eb470d95c09d"
+
 [[package]]
 name = "rustc-hash"
 version = "2.1.1"
@@ -6615,6 +6871,12 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "simd-adler32"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e320a6c5ad31d271ad523dcf3ad13e2767ad8b1cb8f047f75a8aeaf8da139da2"
+
 [[package]]
 name = "simdutf8"
 version = "0.1.5"
@@ -6817,6 +7079,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 
+[[package]]
+name = "str_stack"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9091b6114800a5f2141aee1d1b9d6ca3592ac062dc5decb3764ec5895a47b4eb"
+
 [[package]]
 name = "strength_reduce"
 version = "0.2.4"
@@ -7044,6 +7312,37 @@ dependencies = [
  "num_cpus",
 ]
 
+[[package]]
+name = "tikv-jemalloc-ctl"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "661f1f6a57b3a36dc9174a2c10f19513b4866816e13425d3e418b11cc37bc24c"
+dependencies = [
+ "libc",
+ "paste",
+ "tikv-jemalloc-sys",
+]
+
+[[package]]
+name = "tikv-jemalloc-sys"
+version = "0.6.1+5.3.0-1-ge13ca993e8ccb9ba9847cc330696e02839f328f7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd8aa5b2ab86a2cefa406d889139c162cbb230092f7d1d7cbc1716405d852a3b"
+dependencies = [
+ "cc",
+ "libc",
+]
+
+[[package]]
+name = "tikv-jemallocator"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0359b4327f954e0567e69fb191cf1436617748813819c94b8cd4a431422d053a"
+dependencies = [
+ "libc",
+ "tikv-jemalloc-sys",
+]
+
 [[package]]
 name = "time"
 version = "0.3.45"
diff --git a/Cargo.toml b/Cargo.toml
index 1648a2bd..c5f2fc35 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -74,3 +74,7 @@ rand = "0.9"
 rocksdb = "0.24"
 reqwest = { version = "0.12", default-features = false, features = ["rustls-tls"] }
 eyre = "0.6"
+
+# Allocator + heap profiling
+tikv-jemallocator = { version = "0.6", features = ["stats", "unprefixed_malloc_on_supported_platforms", "profiling"] }
+jemalloc_pprof = { version = "0.8", features = ["flamegraph"] }
diff --git a/bin/ethlambda/Cargo.toml b/bin/ethlambda/Cargo.toml
index 7a897680..2ecb780d 100644
--- a/bin/ethlambda/Cargo.toml
+++ b/bin/ethlambda/Cargo.toml
@@ -28,5 +28,7 @@ reqwest.workspace = true
 thiserror.workspace = true
 eyre.workspace = true
 
+tikv-jemallocator.workspace = true
+
 [build-dependencies]
 vergen-git2.workspace = true
diff --git a/bin/ethlambda/src/main.rs b/bin/ethlambda/src/main.rs
index 7b68abad..984b20f2 100644
--- a/bin/ethlambda/src/main.rs
+++ b/bin/ethlambda/src/main.rs
@@ -1,6 +1,15 @@
 mod checkpoint_sync;
 mod version;
 
+#[cfg(not(target_env = "msvc"))]
+#[global_allocator]
+static ALLOC: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;
+
+#[cfg(not(target_env = "msvc"))]
+#[allow(non_upper_case_globals)]
+#[unsafe(export_name = "malloc_conf")]
+static malloc_conf: &[u8] = b"prof:true,prof_active:true,lg_prof_sample:19\0";
+
 use std::{
     collections::{BTreeMap, HashMap},
     net::{IpAddr, SocketAddr},
@@ -80,6 +89,10 @@ async fn main() -> eyre::Result<()> {
     println!("{ASCII_ART}");
 
     info!(version = version::CLIENT_VERSION, "Starting ethlambda");
+    #[cfg(not(target_env = "msvc"))]
+    info!("Using jemalloc allocator with heap profiling enabled");
+    #[cfg(target_env = "msvc")]
+    info!("Using system allocator (MSVC target)");
 
     info!(node_key=?options.node_key, "got node key");
 
diff --git a/crates/net/rpc/Cargo.toml b/crates/net/rpc/Cargo.toml
index 65690623..191aaecc 100644
--- a/crates/net/rpc/Cargo.toml
+++ b/crates/net/rpc/Cargo.toml
@@ -19,6 +19,7 @@ ethlambda-storage.workspace = true
 ethlambda-types.workspace = true
 serde.workspace = true
 serde_json.workspace = true
+jemalloc_pprof.workspace = true
 
 [dev-dependencies]
 ethlambda-types.workspace = true
diff --git a/crates/net/rpc/src/heap_profiling.rs b/crates/net/rpc/src/heap_profiling.rs
new file mode 100644
index 00000000..cadef653
--- /dev/null
+++ b/crates/net/rpc/src/heap_profiling.rs
@@ -0,0 +1,74 @@
+//! Heap profiling endpoints backed by jemalloc's built-in profiler.
+//!
+//! Returns pprof-format heap profiles at `/debug/pprof/allocs` and interactive
+//! SVG flamegraphs at `/debug/pprof/allocs/flamegraph`. Only functional on Linux;
+//! other platforms return 501 Not Implemented.
+
+#[cfg(target_os = "linux")]
+mod inner {
+    use axum::{http::StatusCode, response::IntoResponse};
+
+    pub async fn handle_get_heap() -> impl IntoResponse {
+        let Some(prof_ctl) = jemalloc_pprof::PROF_CTL.as_ref() else {
+            return (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                "Heap profiling not enabled",
+            )
+                .into_response();
+        };
+        let mut guard = prof_ctl.lock().await;
+        match guard.dump_pprof() {
+            Ok(pprof) => (
+                StatusCode::OK,
+                [("content-type", "application/octet-stream")],
+                pprof,
+            )
+                .into_response(),
+            Err(err) => (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                format!("Failed to dump heap profile: {err}"),
+            )
+                .into_response(),
+        }
+    }
+
+    pub async fn handle_get_heap_flamegraph() -> impl IntoResponse {
+        let Some(prof_ctl) = jemalloc_pprof::PROF_CTL.as_ref() else {
+            return (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                "Heap profiling not enabled",
+            )
+                .into_response();
+        };
+        let mut guard = prof_ctl.lock().await;
+        match guard.dump_flamegraph() {
+            Ok(svg) => (StatusCode::OK, [("content-type", "image/svg+xml")], svg).into_response(),
+            Err(err) => (
+                StatusCode::INTERNAL_SERVER_ERROR,
+                format!("Failed to dump flamegraph: {err}"),
+            )
+                .into_response(),
+        }
+    }
+}
+
+#[cfg(not(target_os = "linux"))]
+mod inner {
+    use axum::{http::StatusCode, response::IntoResponse};
+
+    pub async fn handle_get_heap() -> impl IntoResponse {
+        (
+            StatusCode::NOT_IMPLEMENTED,
+            "Heap profiling is only available on Linux",
+        )
+    }
+
+    pub async fn handle_get_heap_flamegraph() -> impl IntoResponse {
+        (
+            StatusCode::NOT_IMPLEMENTED,
+            "Heap profiling is only available on Linux",
+        )
+    }
+}
+
+pub use inner::{handle_get_heap, handle_get_heap_flamegraph};
diff --git a/crates/net/rpc/src/lib.rs b/crates/net/rpc/src/lib.rs
index 40048aee..487af7fd 100644
--- a/crates/net/rpc/src/lib.rs
+++ b/crates/net/rpc/src/lib.rs
@@ -8,13 +8,18 @@ pub(crate) const JSON_CONTENT_TYPE: &str = "application/json; charset=utf-8";
 pub(crate) const SSZ_CONTENT_TYPE: &str = "application/octet-stream";
 
 mod fork_choice;
+mod heap_profiling;
 pub mod metrics;
 
 pub async fn start_rpc_server(address: SocketAddr, store: Store) -> Result<(), std::io::Error> {
     let metrics_router = metrics::start_prometheus_metrics_api();
     let api_router = build_api_router(store);
+    let debug_router = build_debug_router();
 
-    let app = Router::new().merge(metrics_router).merge(api_router);
+    let app = Router::new()
+        .merge(metrics_router)
+        .merge(api_router)
+        .merge(debug_router);
 
     let listener = tokio::net::TcpListener::bind(address).await?;
     axum::serve(listener, app).await?;
@@ -38,6 +43,16 @@ fn build_api_router(store: Store) -> Router {
         .with_state(store)
 }
 
+/// Build the debug router for profiling endpoints.
+fn build_debug_router() -> Router {
+    Router::new()
+        .route("/debug/pprof/allocs", get(heap_profiling::handle_get_heap))
+        .route(
+            "/debug/pprof/allocs/flamegraph",
+            get(heap_profiling::handle_get_heap_flamegraph),
+        )
+}
+
 async fn get_latest_finalized_state(
     axum::extract::State(store): axum::extract::State<Store>,
 ) -> impl IntoResponse {