diff --git a/.github/workflows/build_and_test.yml b/.github/workflows/build_and_test.yml
index fb330eab760..7558f76ff3d 100644
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -80,6 +80,8 @@ jobs:
       env:
         CARGO_PROFILE_RELEASE_STRIP: 'true'
         CARGO_PROFILE_RELEASE_CODEGEN_UNITS: '1'
+        # jemalloc fixes its page size at build time; 64 KiB pages also run on 4 and 16 KiB kernels.
+        JEMALLOC_SYS_WITH_LG_PAGE: '16'
       run: cargo build --release --bin flow_cli
     - name: Create artifacts
       run: |-
diff --git a/rust_port/Cargo.lock b/rust_port/Cargo.lock
index d13d8fca737..0a98c3aa1b2 100644
--- a/rust_port/Cargo.lock
+++ b/rust_port/Cargo.lock
@@ -559,6 +559,7 @@ dependencies = [
  "lsp-types",
  "serde",
  "serde_json",
+ "tikv-jemallocator",
 ]
 
 [[package]]
@@ -3472,6 +3473,26 @@ dependencies = [
  "syn 3.0.9",
 ]
 
+[[package]]
+name = "tikv-jemalloc-sys"
+version = "0.7.1+5.3.1-0-g81034ce1f1373e37dc865038e1bc8eeecf559ce8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a2825c78386b4ae0314074867860ba9577875de945f05992c38815cbec327f0"
+dependencies = [
+ "cc",
+ "libc",
+]
+
+[[package]]
+name = "tikv-jemallocator"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "249f09e49ab1609436f34c776e84231bead18d6a955f119f939bdc1d847561bd"
+dependencies = [
+ "libc",
+ "tikv-jemalloc-sys",
+]
+
 [[package]]
 name = "tokio"
 version = "1.53.2"
diff --git a/rust_port/crates/flow_cli/Cargo.toml b/rust_port/crates/flow_cli/Cargo.toml
index bc730b14c08..925e9c6a962 100644
--- a/rust_port/crates/flow_cli/Cargo.toml
+++ b/rust_port/crates/flow_cli/Cargo.toml
@@ -72,5 +72,8 @@ lsp-types = "0.97"
 serde = { version = "1.0.229", features = ["derive", "rc"] }
 serde_json = { version = "1.0.154", features = ["alloc", "float_roundtrip", "raw_value", "unbounded_depth"] }
 
+[target.'cfg(target_os = "linux")'.dependencies]
+tikv-jemallocator = { version = "0.7.0", features = ["background_threads"] }
+
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ["cfg(fbcode_build)"]}
diff --git a/rust_port/crates/flow_cli/src/main.rs b/rust_port/crates/flow_cli/src/main.rs
index d47165140ac..17dcfebe50b 100644
--- a/rust_port/crates/flow_cli/src/main.rs
+++ b/rust_port/crates/flow_cli/src/main.rs
@@ -10,6 +10,12 @@
 #[used]
 static malloc_conf: &str = "metadata_thp:always\0";
 
+// Buck builds pick their allocator with `fbcode.default_allocator`, which replaces `malloc` for the
+// whole binary, so a Rust global allocator there could link a second copy of jemalloc.
+#[cfg(all(not(fbcode_build), target_os = "linux"))]
+#[global_allocator]
+static GLOBAL: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;
+
 fn main() {
     #[cfg(windows)]
     {