diff --git a/DESCRIPTION b/DESCRIPTION
index 26fe812d..1ddd209d 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: orderly2
 Title: Orderly Next Generation
-Version: 1.99.32
+Version: 1.99.33
 Authors@R: c(person("Rich", "FitzJohn", role = c("aut", "cre"),
                     email = "rich.fitzjohn@gmail.com"),
              person("Robert", "Ashton", role = "aut"),
diff --git a/R/location_http.R b/R/location_http.R
index 66205a03..47e84f3d 100644
--- a/R/location_http.R
+++ b/R/location_http.R
@@ -70,9 +70,16 @@ orderly_location_http <- R6::R6Class(
     },
 
     push_file = function(src, hash) {
+      size <- file.info(src)$size
+      con <- file(src, "rb")
+      withr::defer(close(con))
+
       res <- private$client$request(
         sprintf("/file/%s", hash),
-        function(r) httr2::req_body_file(r, src, "application/octet-stream"))
+        function(r) {
+          http_body_connection(r, con, size, "application/octet-stream")
+        })
+
 
       invisible(NULL)
     },
diff --git a/R/outpack_http_client.R b/R/outpack_http_client.R
index 94a33c55..6954f8b5 100644
--- a/R/outpack_http_client.R
+++ b/R/outpack_http_client.R
@@ -33,6 +33,22 @@ outpack_http_client <- R6::R6Class(
     }
   ))
 
+
+#' Attach a connection as the request's body.
+#'
+#' It is the caller's responsibility to keep the connection open for the
+#' duration of the request and to close it afterwards.
+http_body_connection <- function(request, con, size, type) {
+  request <- httr2::req_headers(request, "Content-Type" = type)
+  request <- httr2::req_options(
+    request,
+    post = TRUE,
+    readfunction = function(nbytes, ...) readBin(con, "raw", nbytes),
+    seekfunction = function(offset, ...) seed(con, offset),
+    postfieldsize_large = size
+  )
+}
+
 http_client_request <- function(url, customize = identity, download = NULL,
                                 parse_json = TRUE) {
   req <- httr2::request(url)