diff --git a/io/sys/darwin/file.c b/io/sys/darwin/file.c
index 35ed94b..0f5e72d 100644
--- a/io/sys/darwin/file.c
+++ b/io/sys/darwin/file.c
@@ -206,7 +206,7 @@ enum b_status b_file_open_shadow(
 	return B_SUCCESS;
 }
 
-enum b_status stream_close(struct b_stream *stream)
+static enum b_status stream_close(struct b_stream *stream)
 {
 	struct b_file *file = stream->s_ptr;
 	b_file_release(file);
@@ -214,7 +214,7 @@ enum b_status stream_close(struct b_stream *stream)
 	return B_SUCCESS;
 }
 
-enum b_status stream_getc(struct b_stream *stream, int *out)
+static enum b_status stream_getc(struct b_stream *stream, int *out)
 {
 	struct b_file *file = stream->s_ptr;
 	char c;
@@ -235,7 +235,7 @@ enum b_status stream_getc(struct b_stream *stream, int *out)
 	return B_SUCCESS;
 }
 
-enum b_status stream_read(
+static enum b_status stream_read(
 	struct b_stream *stream, unsigned char *buf, size_t max, size_t *nr_read)
 {
 	struct b_file *file = stream->s_ptr;
@@ -248,7 +248,7 @@ enum b_status stream_read(
 	return status;
 }
 
-enum b_status stream_write(
+static enum b_status stream_write(
 	struct b_stream *stream, const unsigned char *buf, size_t count,
 	size_t *nr_written)
 {
@@ -262,7 +262,7 @@ enum b_status stream_write(
 	return status;
 }
 
-enum b_status stream_seek(
+static enum b_status stream_seek(
 	struct b_stream *stream, long long offset, b_stream_seek_origin origin)
 {
 	b_seek_basis basis;