diff --git a/bzip_extent_writer.cc b/bzip_extent_writer.cc
index 7cde7ba..14a0f63 100644
--- a/bzip_extent_writer.cc
+++ b/bzip_extent_writer.cc
@@ -9,7 +9,7 @@
 namespace chromeos_update_engine {
 
 namespace {
-const vector<char>::size_type kOutputBufferLength = 16 * 1024;
+const chromeos::Blob::size_type kOutputBufferLength = 16 * 1024;
 }
 
 bool BzipExtentWriter::Init(FileDescriptorPtr fd,
@@ -26,23 +26,23 @@
 }
 
 bool BzipExtentWriter::Write(const void* bytes, size_t count) {
-  vector<char> output_buffer(kOutputBufferLength);
+  chromeos::Blob output_buffer(kOutputBufferLength);
 
   // Copy the input data into |input_buffer_| only if |input_buffer_| already
   // contains unconsumed data. Otherwise, process the data directly from the
   // source.
-  const char* input = reinterpret_cast<const char*>(bytes);
-  const char* input_end = input + count;
+  const uint8_t* input = reinterpret_cast<const uint8_t*>(bytes);
+  const uint8_t* input_end = input + count;
   if (!input_buffer_.empty()) {
     input_buffer_.insert(input_buffer_.end(), input, input_end);
-    input = &input_buffer_[0];
+    input = input_buffer_.data();
     input_end = input + input_buffer_.size();
   }
-  stream_.next_in = const_cast<char*>(input);
+  stream_.next_in = reinterpret_cast<char*>(const_cast<uint8_t*>(input));
   stream_.avail_in = input_end - input;
 
   for (;;) {
-    stream_.next_out = &output_buffer[0];
+    stream_.next_out = reinterpret_cast<char*>(output_buffer.data());
     stream_.avail_out = output_buffer.size();
 
     int rc = BZ2_bzDecompress(&stream_);
@@ -52,18 +52,18 @@
       break;  // got no new bytes
 
     TEST_AND_RETURN_FALSE(
-        next_->Write(&output_buffer[0],
+        next_->Write(output_buffer.data(),
                      output_buffer.size() - stream_.avail_out));
 
     if (rc == BZ_STREAM_END)
-      CHECK_EQ(stream_.avail_in, static_cast<unsigned int>(0));
+      CHECK_EQ(stream_.avail_in, 0u);
     if (stream_.avail_in == 0)
       break;  // no more input to process
   }
 
   // Store unconsumed data (if any) in |input_buffer_|.
   if (stream_.avail_in || !input_buffer_.empty()) {
-    vector<char> new_input_buffer(input_end - stream_.avail_in, input_end);
+    chromeos::Blob new_input_buffer(input_end - stream_.avail_in, input_end);
     new_input_buffer.swap(input_buffer_);
   }