diff --git a/benchmark/alt_bn_128.cpp b/benchmark/alt_bn_128.cpp
index 5ccb1e09be..da1bda15f9 100644
--- a/benchmark/alt_bn_128.cpp
+++ b/benchmark/alt_bn_128.cpp
@@ -4,7 +4,7 @@
 
 #include <benchmark.hpp>
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 using bytes = std::vector<char>;
 using g1g2_pair = std::vector<std::string>;
diff --git a/benchmark/benchmark.cpp b/benchmark/benchmark.cpp
index bf93c9c239..c72040ab8f 100644
--- a/benchmark/benchmark.cpp
+++ b/benchmark/benchmark.cpp
@@ -5,7 +5,7 @@
 
 #include <benchmark.hpp>
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 // update this map when a new feature is supported
 // key is the name and value is the function doing benchmarking
diff --git a/benchmark/benchmark.hpp b/benchmark/benchmark.hpp
index 8f1935ef18..6ac14e4c47 100644
--- a/benchmark/benchmark.hpp
+++ b/benchmark/benchmark.hpp
@@ -7,7 +7,7 @@
 
 #include <fc/crypto/hex.hpp>
 
-namespace benchmark {
+namespace eosio::benchmark {
 using bytes = std::vector<char>;
 
 void set_num_runs(uint32_t runs);
diff --git a/benchmark/blake2.cpp b/benchmark/blake2.cpp
index 19aa59d771..a5c971a492 100644
--- a/benchmark/blake2.cpp
+++ b/benchmark/blake2.cpp
@@ -2,7 +2,7 @@
 
 #include <benchmark.hpp>
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 void blake2_benchmarking() {
    uint32_t _rounds    = 0x0C;
diff --git a/benchmark/bls.cpp b/benchmark/bls.cpp
index 75c69aef17..97219d338d 100644
--- a/benchmark/bls.cpp
+++ b/benchmark/bls.cpp
@@ -15,10 +15,7 @@ using namespace bls12_381;
 // to run a benchmarking session, in the build directory, type
 // benchmark/benchmark -f bls
 
-namespace eosio::chain {
-// placed in eosio::chain name space so that interface_in_benchmark
-// can access transaction_context's private member max_transaction_time_subjective.
-// interface_in_benchmark is a friend of transaction_context.
+namespace eosio::benchmark {
 
 // To benchmark host functions directly without CDT wrappers,
 // we need to contruct a eosio::chain::webassembly::interface object,
@@ -96,10 +93,6 @@ struct interface_in_benchmark {
    std::unique_ptr<apply_context>               apply_ctx;
    std::unique_ptr<webassembly::interface>      interface;
 };
-} // namespace eosio::chain
-
-
-namespace benchmark {
 
 // utilility to create a random scalar
 std::array<uint64_t, 4> random_scalar()
diff --git a/benchmark/hash.cpp b/benchmark/hash.cpp
index 9bb4aef2b4..9193fae80d 100644
--- a/benchmark/hash.cpp
+++ b/benchmark/hash.cpp
@@ -10,7 +10,7 @@
 
 using namespace fc;
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 void hash_benchmarking() {
    std::string small_message = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ01";
diff --git a/benchmark/key.cpp b/benchmark/key.cpp
index 3d6973d806..cdc8707d0c 100644
--- a/benchmark/key.cpp
+++ b/benchmark/key.cpp
@@ -9,7 +9,7 @@ using namespace fc::crypto;
 using namespace fc;
 using namespace std::literals;
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 void k1_sign_benchmarking() {
    auto payload = "Test Cases";
diff --git a/benchmark/main.cpp b/benchmark/main.cpp
index eadc35ede4..f8d6663eed 100644
--- a/benchmark/main.cpp
+++ b/benchmark/main.cpp
@@ -12,7 +12,7 @@ int main(int argc, char* argv[]) {
    uint32_t num_runs = 1;
    std::string feature_name;
 
-   auto features = benchmark::get_features();
+   auto features = eosio::benchmark::get_features();
 
    options_description cli ("benchmark command line options");
    cli.add_options()
@@ -61,8 +61,8 @@ int main(int argc, char* argv[]) {
       std::cerr << "unknown exception" << std::endl;
    }
 
-   benchmark::set_num_runs(num_runs);
-   benchmark::print_header();
+   eosio::benchmark::set_num_runs(num_runs);
+   eosio::benchmark::print_header();
 
    if (feature_name.empty()) {
       for (auto& [name, f]: features) {
diff --git a/benchmark/modexp.cpp b/benchmark/modexp.cpp
index 14d8443331..7bf5fbedeb 100644
--- a/benchmark/modexp.cpp
+++ b/benchmark/modexp.cpp
@@ -5,7 +5,7 @@
 
 #include <benchmark.hpp>
 
-namespace benchmark {
+namespace eosio::benchmark {
 
 void modexp_benchmarking() {
    std::mt19937 r(0x11223344);
diff --git a/libraries/chain/include/eosio/chain/transaction_context.hpp b/libraries/chain/include/eosio/chain/transaction_context.hpp
index f9b719c760..806e75d9dd 100644
--- a/libraries/chain/include/eosio/chain/transaction_context.hpp
+++ b/libraries/chain/include/eosio/chain/transaction_context.hpp
@@ -4,6 +4,10 @@
 #include <eosio/chain/platform_timer.hpp>
 #include <signal.h>
 
+namespace eosio::benchmark {
+   struct interface_in_benchmark; // for benchmark testing
+}
+
 namespace eosio { namespace chain {
 
    struct transaction_checktime_timer {
@@ -92,7 +96,7 @@ namespace eosio { namespace chain {
 
          friend struct controller_impl;
          friend class apply_context;
-         friend struct interface_in_benchmark; // defined in benchmark/bls.cpp
+         friend struct benchmark::interface_in_benchmark; // defined in benchmark/bls.cpp
 
          void add_ram_usage( account_name account, int64_t ram_delta );