diff --git a/server/src/blob.rs b/server/src/blob.rs
index 891e77d990..f1d9fc12d2 100644
--- a/server/src/blob.rs
+++ b/server/src/blob.rs
@@ -1,25 +1,23 @@
-use actix_web::dev::ServiceRequest;
-use actix_web::http::header::ContentLength;
-use actix_web::web::{Header, Payload};
+use std::error::Error as StdError;
+
 use aws_sdk_s3::primitives::ByteStream;
-use aws_sdk_s3::types::{CompletedMultipartUpload, CompletedPart};
 use blake3::Hasher;
-use bytes::BytesMut;
-use futures_util::StreamExt;
+use bytes::{Bytes, BytesMut};
+use futures::stream::StreamExt;
+use futures_util::Stream;
 use size::Size;
 use tracing::*;
 
+use crate::handlers::ApiError;
 use crate::s3::S3Client;
 use crate::{
     config::CONFIG,
     postgres::{self, Pool},
 };
 
-use crate::handlers::{ApiError, HandlerResult};
-
 pub struct Blob {
     pub s3_key: String,
-    pub length: u64,
+    pub length: usize,
     pub inline: Option<Vec<u8>>,
 }
 
@@ -31,213 +29,105 @@ fn random_key() -> String {
 }
 
 #[instrument(level = "debug", skip_all, fields(s3_bucket))]
-pub async fn upload(
+pub async fn upload<S, E>(
     s3: &S3Client,
     pool: &Pool,
-    request: &mut ServiceRequest,
-    payload: Payload,
-) -> Result<Blob, ApiError> {
+    size: Option<Size>,
+    mut source: S,
+) -> Result<Blob, ApiError>
+where
+    S: Stream<Item = Result<Bytes, E>> + Unpin,
+    E: StdError + Send + Sync + 'static,
+{
     let span = Span::current();
 
     let s3_bucket = &CONFIG.s3_bucket;
-
     span.record("s3_bucket", &s3_bucket);
 
-    if let Ok(length) = request.extract::<Header<ContentLength>>().await
-        && length.0 < Size::from_megabytes(MULTIPART_THRESHOLD).bytes() as usize
+    let blob = if let Some(length) = size
+        && length < Size::from_megabytes(MULTIPART_THRESHOLD)
     {
-        upload_regular(
-            s3,
-            pool,
-            &s3_bucket,
-            length.0 < Size::from_kilobytes(INLINE_THRESHHOLD).bytes() as usize,
-            payload,
-        )
-        .await
-    } else {
-        upload_multipart(s3, pool, &s3_bucket, payload).await
-    }
-}
+        let mut hash = Hasher::new();
 
-#[instrument(level = "debug", skip_all, fields(s3_key))]
-async fn upload_regular(
-    s3: &S3Client,
-    pool: &Pool,
-    s3_bucket: &str,
-    require_inline: bool,
-    payload: Payload,
-) -> Result<Blob, ApiError> {
-    let span = Span::current();
+        let mut buffer = BytesMut::new();
 
-    let payload = payload
-        .to_bytes_limited(Size::from_megabytes(MULTIPART_THRESHOLD).bytes() as usize)
-        .await
-        .map_err(|_| actix_web::error::ErrorPayloadTooLarge("payload too large"))??;
+        while let Some(Ok(chunk)) = source.next().await {
+            buffer.extend_from_slice(&chunk);
 
-    let length = payload.len() as u64;
-    let inline = if require_inline {
-        Some(payload.to_vec())
-    } else {
-        None
-    };
+            if buffer.len() > length.bytes() as usize {
+                return Err(actix_web::error::ErrorPayloadTooLarge("payload too large").into());
+            }
+        }
 
-    let mut hash = Hasher::new();
-    hash.update(&payload);
+        if buffer.len() != length.bytes() as usize {
+            return Err(actix_web::error::ErrorBadRequest("payload size mismatch").into());
+        }
 
-    let hash = hash.finalize().to_hex().to_string();
+        let hash = hash.update(&buffer).finalize().to_hex();
+        let length = buffer.len();
+        let inline = if length < Size::from_kilobytes(INLINE_THRESHHOLD).bytes() as usize {
+            Some(buffer.to_vec())
+        } else {
+            None
+        };
 
-    let s3_key = if let Some(s3_key_found) = postgres::find_blob_by_hash(&pool, &hash).await? {
-        span.record("s3_key", &s3_key_found);
-        debug!(s3_key_found, "blob deduplicated");
-        s3_key_found
+        let s3_key = if let Some(s3_key_found) = postgres::find_blob_by_hash(&pool, &hash).await? {
+            span.record("s3_key", &s3_key_found);
+            debug!(s3_key_found, "blob deduplicated");
+            s3_key_found
+        } else {
+            let s3_key = random_key();
+            span.record("s3_key", &s3_key);
+
+            s3.put_object()
+                .bucket(s3_bucket)
+                .key(&s3_key)
+                .body(ByteStream::from(buffer.freeze()))
+                .send()
+                .await?;
+
+            postgres::insert_blob(&pool, &s3_key, &hash).await?;
+
+            debug!("blob created");
+            s3_key
+        };
+
+        Blob {
+            s3_key,
+            length,
+            inline,
+        }
     } else {
         let s3_key = random_key();
         span.record("s3_key", &s3_key);
 
-        s3.put_object()
-            .bucket(s3_bucket)
-            .key(&s3_key)
-            .body(ByteStream::from(payload))
-            .send()
-            .await?;
+        let upload = crate::s3::multipart_upload(&s3, &s3_bucket, &s3_key, source).await?;
 
-        postgres::insert_blob(&pool, &s3_key, &hash).await?;
+        let hash = upload.hash.to_hex().to_string();
 
-        debug!("blob created");
+        let s3_key = if let Some(s3_key_found) = postgres::find_blob_by_hash(&pool, &hash).await? {
+            debug!(s3_key_found, "blob deduplicated");
 
-        s3_key
-    };
+            // delete uploaded
+            s3.delete_object()
+                .bucket(s3_bucket)
+                .key(s3_key)
+                .send()
+                .await?;
 
-    Ok(Blob {
-        s3_key,
-        length,
-        inline,
-    })
-}
-
-#[instrument(level = "debug", skip_all, fields(upload, s3_key))]
-async fn upload_multipart(
-    s3: &S3Client,
-    pool: &Pool,
-    s3_bucket: &str,
-    mut payload: Payload,
-) -> Result<Blob, ApiError> {
-    let span = Span::current();
-
-    let s3_key = random_key();
-
-    span.record("s3_key", &s3_key);
-
-    let create_multipart = s3
-        .create_multipart_upload()
-        .bucket(s3_bucket)
-        .key(&s3_key)
-        .send()
-        .await?;
-
-    let upload_id = create_multipart.upload_id().unwrap();
-
-    span.record("upload", &upload_id[upload_id.len().saturating_sub(16)..]);
-
-    debug!("upload start");
-
-    let upload_part = async |number, buffer: BytesMut| -> HandlerResult<CompletedPart> {
-        let upload = s3
-            .upload_part()
-            .bucket(s3_bucket)
-            .key(&s3_key)
-            .upload_id(upload_id)
-            .body(buffer.freeze().into())
-            .part_number(number)
-            .send()
-            .await?;
-
-        let part = CompletedPart::builder()
-            .e_tag(upload.e_tag.unwrap())
-            .part_number(number)
-            .build();
-
-        Ok(part)
-    };
-
-    let mut buffer = BytesMut::with_capacity(1024 * 1024 * 6);
-    let mut complete = CompletedMultipartUpload::builder();
-    let mut part_number = 1;
-    let mut hash = Hasher::new();
-    let mut total_in = 0;
-    let mut total_uploaded = 0;
-
-    while let Some(part) = payload.next().await {
-        if let Ok(part) = part {
-            hash.update(&part);
-
-            total_in += part.len();
-
-            buffer.extend_from_slice(&part);
-
-            // each part must be at least 5MB
-            if buffer.len() > 1024 * 1024 * 5 {
-                trace!(length = buffer.len(), part_number, "upload part");
-
-                total_uploaded += buffer.len();
-
-                let uploaded = upload_part(part_number, buffer).await?;
-
-                complete = complete.parts(uploaded);
-
-                buffer = BytesMut::new();
-                part_number += 1;
-            }
+            s3_key_found
         } else {
-            // TODO: cleanup incomplete upload
-            panic!("read error")
+            debug!("blob created");
+            postgres::insert_blob(&pool, &s3_key, &hash).await?;
+            s3_key
+        };
+
+        Blob {
+            s3_key,
+            length: upload.length,
+            inline: None,
         }
-    }
-
-    // the last part
-    if buffer.len() > 0 {
-        total_uploaded += buffer.len();
-
-        trace!(length = buffer.len(), part_number, "upload part");
-        let uploaded = upload_part(part_number, buffer).await?;
-        complete = complete.parts(uploaded);
-    }
-
-    assert_eq!(total_in, total_uploaded);
-
-    let _ = s3
-        .complete_multipart_upload()
-        .bucket(s3_bucket)
-        .key(&s3_key)
-        .multipart_upload(complete.build())
-        .upload_id(upload_id)
-        .send()
-        .await?;
-
-    let hash = hash.finalize().to_hex().to_string();
-
-    debug!(hash, "upload complete");
-
-    let s3_key = if let Some(s3_key_found) = postgres::find_blob_by_hash(&pool, &hash).await? {
-        debug!(s3_key_found, "blob deduplicated");
-
-        // delete uploaded
-        s3.delete_object()
-            .bucket(s3_bucket)
-            .key(s3_key)
-            .send()
-            .await?;
-
-        s3_key_found
-    } else {
-        debug!("blob created");
-        postgres::insert_blob(&pool, &s3_key, &hash).await?;
-        s3_key
     };
 
-    Ok(Blob {
-        s3_key,
-        length: total_uploaded as u64,
-        inline: None,
-    })
+    Ok(blob)
 }
diff --git a/server/src/handlers.rs b/server/src/handlers.rs
index 8a0b979929..5822820c63 100644
--- a/server/src/handlers.rs
+++ b/server/src/handlers.rs
@@ -6,7 +6,7 @@ use actix_web::{
     dev::ServiceRequest,
     http::{
         self,
-        header::{self, ContentType},
+        header::{self, ContentLength, ContentType},
     },
     web::{Data, Header, Path, Payload},
 };
@@ -14,6 +14,7 @@ use aws_sdk_s3::error::SdkError;
 use bytes::Bytes;
 use futures_util::Stream;
 use serde::{Deserialize, Serialize};
+use size::Size;
 use tracing::*;
 use uuid::Uuid;
 
@@ -70,12 +71,25 @@ impl<E: Display + std::error::Error + 'static, B: std::fmt::Debug> From<SdkError
     }
 }
 
+trait ServiceRequestExt {
+    async fn content_length(&mut self) -> Option<Size>;
+}
+
+impl ServiceRequestExt for ServiceRequest {
+    async fn content_length(&mut self) -> Option<Size> {
+        self.extract::<Header<ContentLength>>()
+            .await
+            .map(|header| Size::from_bytes(*header.0))
+            .ok()
+    }
+}
+
 #[derive(Serialize, serde::Deserialize, Debug)]
 struct PartData {
     workspace: Uuid,
     key: String,
     part: u32,
-    size: u64,
+    size: usize,
     blob: String,
     etag: String,
 
@@ -129,7 +143,9 @@ pub async fn put(request: HttpRequest, payload: Payload) -> HandlerResult<HttpRe
         }
     }
 
-    let uploaded = upload(&s3, &pool, &mut request, payload).await?;
+    let content_length = request.content_length().await;
+
+    let uploaded = upload(&s3, &pool, content_length, payload).await?;
 
     let part_data = PartData {
         workspace: path.workspace,
@@ -175,7 +191,9 @@ pub async fn patch(request: HttpRequest, payload: Payload) -> HandlerResult<Http
     let pool = request.app_data::<Data<Pool>>().unwrap().to_owned();
     let s3 = request.app_data::<Data<S3Client>>().unwrap().to_owned();
 
-    let uploaded = upload(&s3, &pool, &mut request, payload).await?;
+    let content_length = request.content_length().await;
+
+    let uploaded = upload(&s3, &pool, content_length, payload).await?;
 
     let parts = postgres::find_parts::<PartData>(&pool, path.workspace, &path.key).await?;
 
@@ -291,7 +309,7 @@ pub async fn get(request: HttpRequest) -> HandlerResult<HttpResponse> {
             }
         }
 
-        response.body(SizedStream::new(content_length, stream(parts, s3)))
+        response.body(SizedStream::new(content_length as u64, stream(parts, s3)))
     } else {
         HttpResponse::NotFound().finish()
     };
diff --git a/server/src/s3.rs b/server/src/s3.rs
index e9ce9c3ce7..0ca106f43c 100644
--- a/server/src/s3.rs
+++ b/server/src/s3.rs
@@ -1,3 +1,5 @@
+use std::error::Error as StdError;
+
 use anyhow::Result;
 use aws_config::BehaviorVersion;
 use aws_sdk_s3::{
@@ -32,13 +34,17 @@ pub struct Upload {
     pub length: usize,
 }
 
-async fn multipart_upload_stream(
+async fn multipart_upload_stream<S, E>(
     s3: &S3Client,
     bucket: &str,
     key: &str,
     upload_id: &str,
-    mut source: impl Stream<Item = Result<Bytes, std::io::Error>> + Unpin,
-) -> Result<(CompletedMultipartUpload, Upload)> {
+    mut source: S,
+) -> Result<(CompletedMultipartUpload, Upload)>
+where
+    S: Stream<Item = Result<Bytes, E>> + Unpin,
+    E: StdError + Send + Sync + 'static,
+{
     debug!("upload start");
 
     let upload_part = async |number, buffer: Bytes| -> Result<CompletedPart> {
@@ -68,7 +74,7 @@ async fn multipart_upload_stream(
     let mut length = 0;
 
     while let Some(part) = source.next().await {
-        let part = part?;
+        let part = part.map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))?;
 
         hash.update(&part);
 
@@ -108,12 +114,16 @@ async fn multipart_upload_stream(
 }
 
 #[tracing::instrument(level = "debug", skip_all)]
-pub async fn multipart_upload<S>(
+pub async fn multipart_upload<S, E>(
     s3: &S3Client,
     bucket: &str,
     key: &str,
-    source: impl Stream<Item = Result<Bytes, std::io::Error>> + Unpin,
-) -> Result<Upload> {
+    source: S,
+) -> Result<Upload>
+where
+    S: Stream<Item = Result<Bytes, E>> + Unpin,
+    E: StdError + Send + Sync + 'static,
+{
     let span = Span::current();
 
     let create_multipart = s3