diff --git a/payload_generator/cow_size_estimator.cc b/payload_generator/cow_size_estimator.cc
index 3eb0aca..f3f5264 100644
--- a/payload_generator/cow_size_estimator.cc
+++ b/payload_generator/cow_size_estimator.cc
@@ -16,12 +16,13 @@
 
 #include "update_engine/payload_generator/cow_size_estimator.h"
 
+#include <string>
 #include <utility>
 #include <vector>
 
+#include <android-base/unique_fd.h>
 #include <libsnapshot/cow_writer.h>
 
-#include "android-base/unique_fd.h"
 #include "update_engine/common/cow_operation_convert.h"
 #include "update_engine/payload_consumer/vabc_partition_writer.h"
 #include "update_engine/update_metadata.pb.h"
@@ -64,9 +65,11 @@
     const google::protobuf::RepeatedPtrField<InstallOperation>& operations,
     const google::protobuf::RepeatedPtrField<CowMergeOperation>&
         merge_operations,
-    size_t block_size) {
+    size_t block_size,
+    std::string compression) {
   android::snapshot::CowWriter cow_writer{
-      {.block_size = static_cast<uint32_t>(block_size), .compression = "gz"}};
+      {.block_size = static_cast<uint32_t>(block_size),
+       .compression = std::move(compression)}};
   // CowWriter treats -1 as special value, will discard all the data but still
   // reports Cow size. Good for estimation purposes
   cow_writer.Initialize(android::base::borrowed_fd{-1});
diff --git a/payload_generator/cow_size_estimator.h b/payload_generator/cow_size_estimator.h
index cba89b5..cad4bad 100644
--- a/payload_generator/cow_size_estimator.h
+++ b/payload_generator/cow_size_estimator.h
@@ -14,10 +14,12 @@
 // limitations under the License.
 //
 #include <cstddef>
+#include <string>
 
 #include <update_engine/update_metadata.pb.h>
 
 #include "update_engine/payload_consumer/file_descriptor.h"
+#include "update_engine/payload_generator/delta_diff_generator.h"
 
 namespace chromeos_update_engine {
 // Given file descriptor to the source image, target image, and list of
@@ -31,6 +33,7 @@
     const google::protobuf::RepeatedPtrField<InstallOperation>& operations,
     const google::protobuf::RepeatedPtrField<CowMergeOperation>&
         merge_operations,
-    size_t block_size);
+    size_t block_size,
+    std::string compression);
 
 }  // namespace chromeos_update_engine
diff --git a/payload_generator/delta_diff_generator.cc b/payload_generator/delta_diff_generator.cc
index 74014d9..a43c782 100644
--- a/payload_generator/delta_diff_generator.cc
+++ b/payload_generator/delta_diff_generator.cc
@@ -132,11 +132,12 @@
       *operations.Add() = aop.op;
     }
     *cow_size_ = EstimateCowSize(
-        source_fd,
+        std::move(source_fd),
         std::move(target_fd),
-        operations,
+        std::move(operations),
         {cow_merge_sequence_->begin(), cow_merge_sequence_->end()},
-        config_.block_size);
+        config_.block_size,
+        config_.target.dynamic_partition_metadata->vabc_compression_param());
     LOG(INFO) << "Estimated COW size for partition: " << new_part_.name << " "
               << *cow_size_;
   }
diff --git a/payload_generator/payload_file.cc b/payload_generator/payload_file.cc
index 4334066..d303cfb 100644
--- a/payload_generator/payload_file.cc
+++ b/payload_generator/payload_file.cc
@@ -74,6 +74,8 @@
 
   if (config.disable_vabc) {
     manifest_.mutable_dynamic_partition_metadata()->set_vabc_enabled(false);
+    manifest_.mutable_dynamic_partition_metadata()->set_vabc_compression_param(
+        "");
   }
   if (config.is_partial_update) {
     manifest_.set_partial_update(true);
diff --git a/payload_generator/payload_generation_config.cc b/payload_generator/payload_generation_config.cc
index f5a7062..73c9ab3 100644
--- a/payload_generator/payload_generation_config.cc
+++ b/payload_generator/payload_generation_config.cc
@@ -180,7 +180,10 @@
   if (store.GetBoolean("virtual_ab_compression", &vabc_enabled)) {
     metadata->set_vabc_enabled(vabc_enabled);
   }
-
+  // We use "gz" compression by default for VABC.
+  if (metadata->vabc_enabled()) {
+    metadata->set_vabc_compression_param("gz");
+  }
   dynamic_partition_metadata = std::move(metadata);
   return true;
 }
diff --git a/scripts/update_payload/update_metadata_pb2.py b/scripts/update_payload/update_metadata_pb2.py
index 1641229..9aef9f2 100644
--- a/scripts/update_payload/update_metadata_pb2.py
+++ b/scripts/update_payload/update_metadata_pb2.py
@@ -20,7 +20,7 @@
   package='chromeos_update_engine',
   syntax='proto2',
   serialized_options=_b('H\003'),
-  serialized_pb=_b('\n\x15update_metadata.proto\x12\x16\x63hromeos_update_engine\"1\n\x06\x45xtent\x12\x13\n\x0bstart_block\x18\x01 \x01(\x04\x12\x12\n\nnum_blocks\x18\x02 \x01(\x04\"\x9f\x01\n\nSignatures\x12@\n\nsignatures\x18\x01 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x1aO\n\tSignature\x12\x13\n\x07version\x18\x01 \x01(\rB\x02\x18\x01\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\x12\x1f\n\x17unpadded_signature_size\x18\x03 \x01(\x07\"+\n\rPartitionInfo\x12\x0c\n\x04size\x18\x01 \x01(\x04\x12\x0c\n\x04hash\x18\x02 \x01(\x0c\"\x8f\x01\n\tImageInfo\x12\x11\n\x05\x62oard\x18\x01 \x01(\tB\x02\x18\x01\x12\x0f\n\x03key\x18\x02 \x01(\tB\x02\x18\x01\x12\x13\n\x07\x63hannel\x18\x03 \x01(\tB\x02\x18\x01\x12\x13\n\x07version\x18\x04 \x01(\tB\x02\x18\x01\x12\x19\n\rbuild_channel\x18\x05 \x01(\tB\x02\x18\x01\x12\x19\n\rbuild_version\x18\x06 \x01(\tB\x02\x18\x01\"\xee\x03\n\x10InstallOperation\x12;\n\x04type\x18\x01 \x02(\x0e\x32-.chromeos_update_engine.InstallOperation.Type\x12\x13\n\x0b\x64\x61ta_offset\x18\x02 \x01(\x04\x12\x13\n\x0b\x64\x61ta_length\x18\x03 \x01(\x04\x12\x33\n\x0bsrc_extents\x18\x04 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\nsrc_length\x18\x05 \x01(\x04\x12\x33\n\x0b\x64st_extents\x18\x06 \x03(\x0b\x32\x1e.chromeos_update_engine.Extent\x12\x12\n\ndst_length\x18\x07 \x01(\x04\x12\x18\n\x10\x64\x61ta_sha256_hash\x18\x08 \x01(\x0c\x12\x17\n\x0fsrc_sha256_hash\x18\t \x01(\x0c\"\xad\x01\n\x04Type\x12\x0b\n\x07REPLACE\x10\x00\x12\x0e\n\nREPLACE_BZ\x10\x01\x12\x0c\n\x04MOVE\x10\x02\x1a\x02\x08\x01\x12\x0e\n\x06\x42SDIFF\x10\x03\x1a\x02\x08\x01\x12\x0f\n\x0bSOURCE_COPY\x10\x04\x12\x11\n\rSOURCE_BSDIFF\x10\x05\x12\x0e\n\nREPLACE_XZ\x10\x08\x12\x08\n\x04ZERO\x10\x06\x12\x0b\n\x07\x44ISCARD\x10\x07\x12\x11\n\rBROTLI_BSDIFF\x10\n\x12\x0c\n\x08PUFFDIFF\x10\t\"\xcf\x01\n\x11\x43owMergeOperation\x12<\n\x04type\x18\x01 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\x01(\x08\"c\n\x08\x41pexInfo\x12\x14\n\x0cpackage_name\x18\x01 \x01(\t\x12\x0f\n\x07version\x18\x02 \x01(\x03\x12\x15\n\ris_compressed\x18\x03 \x01(\x08\x12\x19\n\x11\x64\x65\x63ompressed_size\x18\x04 \x01(\x03\"C\n\x0c\x41pexMetadata\x12\x33\n\tapex_info\x18\x01 \x03(\x0b\x32 .chromeos_update_engine.ApexInfo\"\x9e\x07\n\x14\x44\x65ltaArchiveManifest\x12H\n\x12install_operations\x18\x01 \x03(\x0b\x32(.chromeos_update_engine.InstallOperationB\x02\x18\x01\x12O\n\x19kernel_install_operations\x18\x02 \x03(\x0b\x32(.chromeos_update_engine.InstallOperationB\x02\x18\x01\x12\x18\n\nblock_size\x18\x03 \x01(\r:\x04\x34\x30\x39\x36\x12\x19\n\x11signatures_offset\x18\x04 \x01(\x04\x12\x17\n\x0fsignatures_size\x18\x05 \x01(\x04\x12\x42\n\x0fold_kernel_info\x18\x06 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12\x42\n\x0fnew_kernel_info\x18\x07 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12\x42\n\x0fold_rootfs_info\x18\x08 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12\x42\n\x0fnew_rootfs_info\x18\t \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12=\n\x0eold_image_info\x18\n \x01(\x0b\x32!.chromeos_update_engine.ImageInfoB\x02\x18\x01\x12=\n\x0enew_image_info\x18\x0b \x01(\x0b\x32!.chromeos_update_engine.ImageInfoB\x02\x18\x01\x12\x18\n\rminor_version\x18\x0c \x01(\r:\x01\x30\x12;\n\npartitions\x18\r \x03(\x0b\x32\'.chromeos_update_engine.PartitionUpdate\x12\x15\n\rmax_timestamp\x18\x0e \x01(\x03\x12T\n\x1a\x64ynamic_partition_metadata\x18\x0f \x01(\x0b\x32\x30.chromeos_update_engine.DynamicPartitionMetadata\x12\x16\n\x0epartial_update\x18\x10 \x01(\x08\x12\x33\n\tapex_info\x18\x11 \x03(\x0b\x32 .chromeos_update_engine.ApexInfoB\x02H\x03')
+  serialized_pb=_b('\n\x15update_metadata.proto\x12\x16\x63hromeos_update_engine\"1\n\x06\x45xtent\x12\x13\n\x0bstart_block\x18\x01 \x01(\x04\x12\x12\n\nnum_blocks\x18\x02 \x01(\x04\"\x9f\x01\n\nSignatures\x12@\n\nsignatures\x18\x01 \x03(\x0b\x32,.chromeos_update_engine.Signatures.Signature\x1aO\n\tSignature\x12\x13\n\x07version\x18\x01 \x01(\rB\x02\x18\x01\x12\x0c\n\x04\x64\x61ta\x18\x02 \x01(\x0c\x12\x1f\n\x17unpadded_signature_size\x18\x03 \x01(\x07\"+\n\rPartitionInfo\x12\x0c\n\x04size\x18\x01 \x01(\x04\x12\x0c\n\x04hash\x18\x02 \x01(\x0c\"\x8f\x01\n\tImageInfo\x12\x11\n\x05\x62oard\x18\x01 \x01(\tB\x02\x18\x01\x12\x0f\n\x03key\x18\x02 \x01(\tB\x02\x18\x01\x12\x13\n\x07\x63hannel\x18\x03 \x01(\tB\x02\x18\x01\x12\x13\n\x07version\x18\x04 \x01(\tB\x02\x18\x01\x12\x19\n\rbuild_channel\x18\x05 \x01(\tB\x02\x18\x01\x12\x19\n\rbuild_version\x18\x06 \x01(\tB\x02\x18\x01\"\xee\x03\n\x10InstallOperation\x12;\n\x04type\x18\x01 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\x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12\x42\n\x0fold_rootfs_info\x18\x08 \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12\x42\n\x0fnew_rootfs_info\x18\t \x01(\x0b\x32%.chromeos_update_engine.PartitionInfoB\x02\x18\x01\x12=\n\x0eold_image_info\x18\n \x01(\x0b\x32!.chromeos_update_engine.ImageInfoB\x02\x18\x01\x12=\n\x0enew_image_info\x18\x0b \x01(\x0b\x32!.chromeos_update_engine.ImageInfoB\x02\x18\x01\x12\x18\n\rminor_version\x18\x0c \x01(\r:\x01\x30\x12;\n\npartitions\x18\r \x03(\x0b\x32\'.chromeos_update_engine.PartitionUpdate\x12\x15\n\rmax_timestamp\x18\x0e \x01(\x03\x12T\n\x1a\x64ynamic_partition_metadata\x18\x0f \x01(\x0b\x32\x30.chromeos_update_engine.DynamicPartitionMetadata\x12\x16\n\x0epartial_update\x18\x10 \x01(\x08\x12\x33\n\tapex_info\x18\x11 \x03(\x0b\x32 .chromeos_update_engine.ApexInfoB\x02H\x03')
 )
 
 
@@ -683,6 +683,13 @@
       message_type=None, enum_type=None, containing_type=None,
       is_extension=False, extension_scope=None,
       serialized_options=None, file=DESCRIPTOR),
+    _descriptor.FieldDescriptor(
+      name='vabc_compression_param', full_name='chromeos_update_engine.DynamicPartitionMetadata.vabc_compression_param', index=3,
+      number=4, type=9, cpp_type=9, label=1,
+      has_default_value=False, default_value=_b("").decode('utf-8'),
+      message_type=None, enum_type=None, containing_type=None,
+      is_extension=False, extension_scope=None,
+      serialized_options=None, file=DESCRIPTOR),
   ],
   extensions=[
   ],
@@ -696,7 +703,7 @@
   oneofs=[
   ],
   serialized_start=2082,
-  serialized_end=2219,
+  serialized_end=2251,
 )
 
 
@@ -747,8 +754,8 @@
   extension_ranges=[],
   oneofs=[
   ],
-  serialized_start=2221,
-  serialized_end=2320,
+  serialized_start=2253,
+  serialized_end=2352,
 )
 
 
@@ -778,8 +785,8 @@
   extension_ranges=[],
   oneofs=[
   ],
-  serialized_start=2322,
-  serialized_end=2389,
+  serialized_start=2354,
+  serialized_end=2421,
 )
 
 
@@ -921,8 +928,8 @@
   extension_ranges=[],
   oneofs=[
   ],
-  serialized_start=2392,
-  serialized_end=3318,
+  serialized_start=2424,
+  serialized_end=3350,
 )
 
 _SIGNATURES_SIGNATURE.containing_type = _SIGNATURES
diff --git a/update_metadata.proto b/update_metadata.proto
index a1f093c..bc9e34a 100644
--- a/update_metadata.proto
+++ b/update_metadata.proto
@@ -354,6 +354,11 @@
   // supports it, but not guaranteed.
   // VABC stands for Virtual AB Compression
   optional bool vabc_enabled = 3;
+
+  // The compression algorithm used by VABC. Available ones are "gz", "brotli".
+  // See system/core/fs_mgr/libsnapshot/cow_writer.cpp for available options,
+  // as this parameter is ultimated forwarded to libsnapshot's CowWriter
+  optional string vabc_compression_param = 4;
 }
 
 // Definition has been duplicated from