diff --git a/builtin/odb--daemon.c b/builtin/odb--daemon.c
index 6cccfd3ceb7f08..f1fd6a8ba9580e 100644
--- a/builtin/odb--daemon.c
+++ b/builtin/odb--daemon.c
@@ -1,5 +1,6 @@
 #include "builtin.h"
 #include "config.h"
+#include "object-file.h"
 #include "object-store.h"
 #include "oidmap.h"
 #include "parse-options.h"
@@ -8,6 +9,7 @@
 #include "thread-utils.h"
 #include "odb-over-ipc.h"
 #include "trace2.h"
+#include "hex.h"
 
 enum my_mode {
 	MODE_UNDEFINED = 0,
@@ -172,6 +174,44 @@ static int odb_ipc_cb__get_oid(struct my_odb_ipc_state *state,
 	return 0;
 }
 
+static int odb_ipc_cb__hash_object(struct my_odb_ipc_state *state,
+				   const char *command, size_t command_len,
+				   ipc_server_reply_cb *reply_cb,
+				   struct ipc_server_reply_data *reply_data)
+{
+	struct odb_over_ipc__hash_object__request *req;
+	struct odb_over_ipc__hash_object__response *resp;
+	const char *content;
+	size_t content_len;
+
+	if (command_len < sizeof(*req))
+		BUG("incorrect size for binary data");
+
+	req = (struct odb_over_ipc__hash_object__request *)command;
+
+	content = command + sizeof(*req);
+	content_len = command_len - sizeof(*req);
+
+	resp = xmalloc(sizeof(*resp));
+	memcpy(&resp->key.key, "hash-object", 11);
+
+	if (index_mem(the_repository->index, &resp->oid, (void *)content,
+		      content_len, req->type, NULL, req->flags) < 0)
+		goto fail;
+
+	reply_cb(reply_data, (const char *)resp, sizeof(*resp));
+
+	return 0;
+
+fail:
+	/*
+	 * Send the client an error response to force it to do
+	 * the work itself.
+	 */
+	reply_cb(reply_data, "error", 6);
+	return 0;
+}
+
 /*
  * This callback handles IPC requests from clients.  We run on an
  * arbitrary thread.
@@ -226,6 +266,18 @@ static int odb_ipc_cb(void *data,
 		return ret;
 	}
 
+	if (!strcmp(command, "hash-object")) {
+		/*
+		 * A client has requested that we hash an object and optionally
+		 * store it in the ODB.
+		 */
+		trace2_region_enter("odb-daemon", "hash-object", NULL);
+		ret = odb_ipc_cb__hash_object(state, command, command_len,
+					      reply_cb, reply_data);
+		trace2_region_leave("odb-daemon", "hash-object", NULL);
+		return 0;
+	}
+
 	// TODO respond to other requests from client.
 	//
 	// TODO decide how to return an error for unknown commands.
diff --git a/object-file.c b/object-file.c
index 2263f64c5ef2df..0ce79a8f241e8c 100644
--- a/object-file.c
+++ b/object-file.c
@@ -2490,10 +2490,10 @@ static int hash_format_check_report(struct fsck_options *opts UNUSED,
 	return 1;
 }
 
-static int index_mem(struct index_state *istate,
-		     struct object_id *oid, void *buf, size_t size,
-		     enum object_type type,
-		     const char *path, unsigned flags)
+int index_mem(struct index_state *istate,
+	      struct object_id *oid, void *buf, size_t size,
+	      enum object_type type,
+	      const char *path, unsigned flags)
 {
 	int ret = 0;
 	int re_allocated = 0;
@@ -2631,6 +2631,10 @@ int index_fd(struct index_state *istate, struct object_id *oid,
 	     enum object_type type, const char *path, unsigned flags)
 {
 	int ret;
+	if (!odb_over_ipc__hash_object(the_repository, oid, fd, type, flags)) {
+		close(fd);
+		return 0;
+	}
 
 	/*
 	 * Call xsize_t() only when needed to avoid potentially unnecessary
diff --git a/object-file.h b/object-file.h
index d6414610f80b73..416ae5d339851c 100644
--- a/object-file.h
+++ b/object-file.h
@@ -20,6 +20,7 @@ extern int fetch_if_missing;
 #define HASH_SILENT 8
 int index_fd(struct index_state *istate, struct object_id *oid, int fd, struct stat *st, enum object_type type, const char *path, unsigned flags);
 int index_path(struct index_state *istate, struct object_id *oid, const char *path, struct stat *st, unsigned flags);
+int index_mem(struct index_state *istate, struct object_id *oid, void *buf, size_t size, enum object_type type, const char *path, unsigned flags);
 
 /*
  * Create the directory containing the named path, using care to be
diff --git a/odb-over-ipc.c b/odb-over-ipc.c
index 881024af4f50e2..1d342b71ebbebd 100644
--- a/odb-over-ipc.c
+++ b/odb-over-ipc.c
@@ -206,4 +206,62 @@ int odb_over_ipc__get_oid(struct repository *r, const struct object_id *oid,
 	return ret;
 }
 
+int odb_over_ipc__hash_object(struct repository *r, struct object_id *oid,
+			      int fd, enum object_type type, unsigned flags)
+{
+	struct odb_over_ipc__hash_object__request req;
+	struct odb_over_ipc__hash_object__response *resp;
+
+	struct strbuf answer = STRBUF_INIT;
+	struct strbuf content = STRBUF_INIT;
+	struct strbuf msg = STRBUF_INIT;
+	int ret;
+
+	if (is_daemon)
+		return -1;
+
+	if (!core_use_odb_over_ipc)
+		return -1;
+
+	if (r != the_repository)	// TODO not dealing with this
+		return -1;
+
+	/*
+	 * Read the content from the file descriptor in to the buffer and then
+	 * send the request over IPC.
+	 */
+	if (strbuf_read(&content, fd, LARGE_PACKET_MAX) < 0)
+		return error_errno("could not read object content");
+
+	memset(&req, 0, sizeof(req));
+	memcpy(req.key.key, "hash-object", 11);
+	req.type = type;
+	req.flags = flags;
+	req.content_size = content.len;
+
+	/* Append the content at the end of the request */
+	strbuf_init(&msg, sizeof(req) + content.len);
+	strbuf_add(&msg, &req, sizeof(req));
+	strbuf_addbuf(&msg, &content);
+
+	ret = odb_over_ipc__command((const char *)msg.buf, msg.len, &answer);
+	if (ret)
+		return ret;
+
+	if (!strncmp(answer.buf, "error", 5)) {
+		trace2_printf("odb-over-ipc: failed");
+		return -1;
+	}
+
+	if (answer.len < sizeof(*resp))
+		BUG("incorrect size for binary data");
+	resp = (struct odb_over_ipc__hash_object__response *)answer.buf;
+
+	oidcpy(oid, &resp->oid);
+
+	strbuf_release(&content);
+	strbuf_release(&answer);
+	return ret;
+}
+
 #endif /* SUPPORTS_SIMPLE_IPC */
diff --git a/odb-over-ipc.h b/odb-over-ipc.h
index 98524dd1c5015a..8fc1f27200731d 100644
--- a/odb-over-ipc.h
+++ b/odb-over-ipc.h
@@ -68,6 +68,20 @@ struct odb_over_ipc__get_oid__response
 	enum object_type type;
 };
 
+struct odb_over_ipc__hash_object__request
+{
+	struct odb_over_ipc__key key;
+	enum object_type type;
+	unsigned flags;
+	size_t content_size;
+};
+
+struct odb_over_ipc__hash_object__response
+{
+	struct odb_over_ipc__key key;
+	struct object_id oid;
+};
+
 /*
  * Connect to an existing `git odb--daemon` process and ask it for
  * an object.  This is intended to be inserted into the client
@@ -82,6 +96,10 @@ struct repository;
 int odb_over_ipc__get_oid(struct repository *r, const struct object_id *oid,
 			  struct object_info *oi, unsigned flags);
 
+
+int odb_over_ipc__hash_object(struct repository *r, struct object_id *oid,
+			      int fd, enum object_type type, unsigned flags);
+
 /*
  * Explicitly shutdown IPC connection to the `git odb--daemon` process.
  * The connection is implicitly created upon the first request and we