diff --git a/src/daemon/db-mgr.cpp b/src/daemon/db-mgr.cpp
index 27c7332..e1ab0fc 100644
--- a/src/daemon/db-mgr.cpp
+++ b/src/daemon/db-mgr.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2021, Regents of the University of California.
+ * Copyright (c) 2014-2022, Regents of the University of California.
  *
  * This file is part of NDNS (Named Data Networking Domain Name Service).
  * See AUTHORS.md for complete list of NDNS authors and contributors.
@@ -150,7 +150,7 @@
   while (nBytesLeft > 0) {
     bool hasDecodingSucceeded;
     name::Component component;
-    std::tie(hasDecodingSucceeded, component) = Block::fromBuffer(buffer, nBytesLeft);
+    std::tie(hasDecodingSucceeded, component) = Block::fromBuffer({buffer, nBytesLeft});
     if (!hasDecodingSucceeded) {
       NDN_THROW(Error("Error while decoding name from the database"));
     }
@@ -213,8 +213,8 @@
   }
 
   sqlite3_bind_int(stmt,  1, zone.getId());
-  sqlite3_bind_text(stmt, 2, key.data(),  key.length(), SQLITE_STATIC);
-  sqlite3_bind_blob(stmt, 3, value.wire(), value.size(), SQLITE_STATIC);
+  sqlite3_bind_text(stmt, 2, key.data(),   key.length(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt, 3, value.data(), value.size(), SQLITE_STATIC);
 
   rc = sqlite3_step(stmt);
   if (rc != SQLITE_DONE) {
@@ -250,8 +250,8 @@
 
   while (sqlite3_step(stmt) == SQLITE_ROW) {
     const char* key = reinterpret_cast<const char*>(sqlite3_column_text(stmt, 0));
-    rtn[string(key)] = Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 1)),
-                             sqlite3_column_bytes(stmt, 1));
+    rtn[string(key)] = Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 1)),
+                                       sqlite3_column_bytes(stmt, 1)));
   }
 
   sqlite3_finalize(stmt);
@@ -364,10 +364,10 @@
   sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
 
   saveName(rrset.getLabel(), stmt, 2);
-  sqlite3_bind_blob(stmt,  3, rrset.getType().wire(),    rrset.getType().size(),    SQLITE_STATIC);
-  sqlite3_bind_blob(stmt,  4, rrset.getVersion().wire(), rrset.getVersion().size(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  3, rrset.getType().data(),    rrset.getType().size(),    SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  4, rrset.getVersion().data(), rrset.getVersion().size(), SQLITE_STATIC);
   sqlite3_bind_int64(stmt, 5, rrset.getTtl().count());
-  sqlite3_bind_blob(stmt,  6, rrset.getData().wire(),    rrset.getData().size(),    SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  6, rrset.getData().data(),    rrset.getData().size(),    SQLITE_STATIC);
 
   rc = sqlite3_step(stmt);
   if (rc != SQLITE_DONE) {
@@ -405,15 +405,15 @@
   sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
 
   saveName(rrset.getLabel(), stmt, 2);
-  sqlite3_bind_blob(stmt, 3, rrset.getType().wire(), rrset.getType().size(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt, 3, rrset.getType().data(), rrset.getType().size(), SQLITE_STATIC);
 
   if (sqlite3_step(stmt) == SQLITE_ROW) {
     rrset.setId(sqlite3_column_int64(stmt, 0));
     rrset.setTtl(time::seconds(sqlite3_column_int64(stmt, 1)));
-    rrset.setVersion(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
-                           sqlite3_column_bytes(stmt, 2)));
-    rrset.setData(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
-                        sqlite3_column_bytes(stmt, 3)));
+    rrset.setVersion(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
+                                     sqlite3_column_bytes(stmt, 2))));
+    rrset.setData(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
+                                  sqlite3_column_bytes(stmt, 3))));
   }
   else {
     rrset.setId(0);
@@ -449,15 +449,15 @@
   sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
 
   saveName(rrset.getLabel(), stmt, 2);
-  sqlite3_bind_blob(stmt, 3, rrset.getType().wire(), rrset.getType().size(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt, 3, rrset.getType().data(), rrset.getType().size(), SQLITE_STATIC);
 
   if (sqlite3_step(stmt) == SQLITE_ROW) {
     rrset.setId(sqlite3_column_int64(stmt, 0));
     rrset.setTtl(time::seconds(sqlite3_column_int64(stmt, 1)));
-    rrset.setVersion(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
-                           sqlite3_column_bytes(stmt, 2)));
-    rrset.setData(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
-                        sqlite3_column_bytes(stmt, 3)));
+    rrset.setVersion(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
+                                     sqlite3_column_bytes(stmt, 2))));
+    rrset.setData(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
+                                  sqlite3_column_bytes(stmt, 3))));
   }
   else {
     rrset.setId(0);
@@ -493,13 +493,13 @@
 
     rrset.setId(sqlite3_column_int64(stmt, 0));
     rrset.setTtl(time::seconds(sqlite3_column_int64(stmt, 1)));
-    rrset.setVersion(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
-                           sqlite3_column_bytes(stmt, 2)));
-    rrset.setData(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
-                        sqlite3_column_bytes(stmt, 3)));
+    rrset.setVersion(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
+                                     sqlite3_column_bytes(stmt, 2))));
+    rrset.setData(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
+                                  sqlite3_column_bytes(stmt, 3))));
     rrset.setLabel(restoreName(stmt, 4));
-    rrset.setType(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 5)),
-                  sqlite3_column_bytes(stmt, 5)));
+    rrset.setType(Block(make_span(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 5)),
+                                  sqlite3_column_bytes(stmt, 5))));
   }
   sqlite3_finalize(stmt);
 
@@ -523,7 +523,7 @@
   }
 
   sqlite3_bind_int64(stmt, 1, zone.getId());
-  sqlite3_bind_blob(stmt,  2, type.wire(), type.size(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  2, type.data(), type.size(), SQLITE_STATIC);
 
   rc = sqlite3_step(stmt);
   if (rc != SQLITE_DONE) {
@@ -578,8 +578,8 @@
   }
 
   sqlite3_bind_int64(stmt, 1, rrset.getTtl().count());
-  sqlite3_bind_blob(stmt,  2, rrset.getVersion().wire(), rrset.getVersion().size(), SQLITE_STATIC);
-  sqlite3_bind_blob(stmt,  3, rrset.getData().wire(),    rrset.getData().size(),    SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  2, rrset.getVersion().data(), rrset.getVersion().size(), SQLITE_STATIC);
+  sqlite3_bind_blob(stmt,  3, rrset.getData().data(),    rrset.getData().size(),    SQLITE_STATIC);
   sqlite3_bind_int64(stmt, 4, rrset.getId());
 
   sqlite3_step(stmt);
diff --git a/src/daemon/rrset-factory.cpp b/src/daemon/rrset-factory.cpp
index cded8e0..eed7ad0 100644
--- a/src/daemon/rrset-factory.cpp
+++ b/src/daemon/rrset-factory.cpp
@@ -60,7 +60,7 @@
 RrsetFactory::onlyCheckZone()
 {
   if (m_checked) {
-    return ;
+    return;
   }
   m_checked = true;
 
@@ -71,7 +71,6 @@
   }
 }
 
-
 std::pair<Rrset, Name>
 RrsetFactory::generateBaseRrset(const Name& label,
                                 const name::Component& type,
@@ -158,10 +157,9 @@
   std::tie(rrset, name) = generateBaseRrset(label, label::TXT_RR_TYPE, version, ttl);
 
   std::vector<Block> rrs;
+  rrs.reserve(strings.size());
   for (const auto& item : strings) {
-    rrs.push_back(makeBinaryBlock(ndns::tlv::RrData,
-                                  item.c_str(),
-                                  item.size()));
+    rrs.push_back(makeBinaryBlock(ndns::tlv::RrData, item.data(), item.size()));
   }
 
   Data data(name);
@@ -274,24 +272,23 @@
 }
 
 template<encoding::Tag TAG>
-inline size_t
-RrsetFactory::wireEncode(EncodingImpl<TAG>& block, const std::vector<Block>& rrs) const
+size_t
+RrsetFactory::wireEncode(EncodingImpl<TAG>& encoder, const std::vector<Block>& rrs) const
 {
   // Content :: = CONTENT-TYPE TLV-LENGTH
   //              Block*
 
   size_t totalLength = 0;
   for (auto iter = rrs.rbegin(); iter != rrs.rend(); ++iter) {
-    totalLength += block.prependBlock(*iter);
+    totalLength += prependBlock(encoder, *iter);
   }
 
-  totalLength += block.prependVarNumber(totalLength);
-  totalLength += block.prependVarNumber(::ndn::tlv::Content);
-
+  totalLength += encoder.prependVarNumber(totalLength);
+  totalLength += encoder.prependVarNumber(ndn::tlv::Content);
   return totalLength;
 }
 
-const Block
+Block
 RrsetFactory::wireEncode(const std::vector<Block>& rrs) const
 {
   EncodingEstimator estimator;
@@ -315,6 +312,5 @@
   return txts;
 }
 
-
 } // namespace ndns
 } // namespace ndn
diff --git a/src/daemon/rrset-factory.hpp b/src/daemon/rrset-factory.hpp
index bffb093..0daa27f 100644
--- a/src/daemon/rrset-factory.hpp
+++ b/src/daemon/rrset-factory.hpp
@@ -106,18 +106,17 @@
   matchCertificate(const Name& certName, const Name& identity);
 
   template<encoding::Tag TAG>
-  inline size_t
-  wireEncode(EncodingImpl<TAG>& block, const std::vector<Block>& rrs) const;
+  size_t
+  wireEncode(EncodingImpl<TAG>& encoder, const std::vector<Block>& rrs) const;
 
-  const Block
+  Block
   wireEncode(const std::vector<Block>& rrs) const;
 
   void
   sign(Data& data);
 
   void
-  setContentType(Data& data, NdnsContentType contentType,
-                 const time::seconds& ttl);
+  setContentType(Data& data, NdnsContentType contentType, const time::seconds& ttl);
 
 private:
   KeyChain& m_keyChain;