diff --git a/pkgs/build-support/node/fetch-npm-deps/src/parse/mod.rs b/pkgs/build-support/node/fetch-npm-deps/src/parse/mod.rs
index b37652ffdf82..86e9120de02f 100644
--- a/pkgs/build-support/node/fetch-npm-deps/src/parse/mod.rs
+++ b/pkgs/build-support/node/fetch-npm-deps/src/parse/mod.rs
@@ -4,7 +4,7 @@ use rayon::prelude::*;
 use serde_json::{Map, Value};
 use std::{
     fs,
-    io::{self, Read},
+    io::Write,
     process::{Command, Stdio},
 };
 use tempfile::{tempdir, TempDir};
@@ -106,7 +106,7 @@ impl Package {
 
         let specifics = match get_hosted_git_url(&resolved)? {
             Some(hosted) => {
-                let mut body = util::get_url_with_retry(&hosted)?;
+                let body = util::get_url_body_with_retry(&hosted)?;
 
                 let workdir = tempdir()?;
 
@@ -120,7 +120,7 @@ impl Package {
                     .stdin(Stdio::piped())
                     .spawn()?;
 
-                io::copy(&mut body, &mut cmd.stdin.take().unwrap())?;
+                cmd.stdin.take().unwrap().write_all(&body)?;
 
                 let exit = cmd.wait()?;
 
@@ -154,13 +154,7 @@ impl Package {
 
     pub fn tarball(&self) -> anyhow::Result<Vec<u8>> {
         match &self.specifics {
-            Specifics::Registry { .. } => {
-                let mut body = Vec::new();
-
-                util::get_url_with_retry(&self.url)?.read_to_end(&mut body)?;
-
-                Ok(body)
-            }
+            Specifics::Registry { .. } => Ok(util::get_url_body_with_retry(&self.url)?),
             Specifics::Git { workdir } => Ok(Command::new("tar")
                 .args([
                     "--sort=name",
diff --git a/pkgs/build-support/node/fetch-npm-deps/src/util.rs b/pkgs/build-support/node/fetch-npm-deps/src/util.rs
index 7a220f681c0d..7dd928fdc43f 100644
--- a/pkgs/build-support/node/fetch-npm-deps/src/util.rs
+++ b/pkgs/build-support/node/fetch-npm-deps/src/util.rs
@@ -4,7 +4,7 @@ use isahc::{
     Body, Request, RequestExt,
 };
 use serde_json::{Map, Value};
-use std::{env, path::Path};
+use std::{env, io::Read, path::Path};
 use url::Url;
 
 pub fn get_url(url: &Url) -> Result<Body, isahc::Error> {
@@ -28,7 +28,7 @@ pub fn get_url(url: &Url) -> Result<Body, isahc::Error> {
     if let Some(host) = url.host_str() {
         if let Ok(npm_tokens) = env::var("NIX_NPM_TOKENS") {
             if let Ok(tokens) = serde_json::from_str::<Map<String, Value>>(&npm_tokens) {
-                if let Some(token) = tokens.get(host).and_then(|val| val.as_str()) {
+                if let Some(token) = tokens.get(host).and_then(serde_json::Value::as_str) {
                     request = request.header("Authorization", format!("Bearer {token}"));
                 }
             }
@@ -38,15 +38,23 @@ pub fn get_url(url: &Url) -> Result<Body, isahc::Error> {
     Ok(request.body(())?.send()?.into_body())
 }
 
-pub fn get_url_with_retry(url: &Url) -> Result<Body, isahc::Error> {
+pub fn get_url_body_with_retry(url: &Url) -> Result<Vec<u8>, isahc::Error> {
     retry(ExponentialBackoff::default(), || {
-        get_url(url).map_err(|err| {
-            if err.is_network() || err.is_timeout() {
-                backoff::Error::transient(err)
-            } else {
-                backoff::Error::permanent(err)
-            }
-        })
+        get_url(url)
+            .and_then(|mut body| {
+                let mut buf = Vec::new();
+
+                body.read_to_end(&mut buf)?;
+
+                Ok(buf)
+            })
+            .map_err(|err| {
+                if err.is_network() || err.is_timeout() {
+                    backoff::Error::transient(err)
+                } else {
+                    backoff::Error::permanent(err)
+                }
+            })
     })
     .map_err(|backoff_err| match backoff_err {
         backoff::Error::Permanent(err)