diff --git a/centipede/command.cc b/centipede/command.cc
index 06cc79f0..972a0562 100644
--- a/centipede/command.cc
+++ b/centipede/command.cc
@@ -205,7 +205,7 @@ std::string Command::ToString() const {
   ss.reserve(/*env*/ 1 + options_.env_diff.size() + /*path*/ 1 +
              /*args*/ options_.args.size() + /*out/err*/ 2);
   // env.
-  ss.push_back("env");
+  ss.push_back("exec env");
   std::vector<std::string> env_to_set;
   env_to_set.reserve(options_.env_diff.size());
   // Arguments that unset environment variables must appear first.
@@ -285,7 +285,7 @@ bool Command::StartForkServer(std::string_view temp_dir_path,
   {
     CENTIPEDE_FORK_SERVER_FIFO0="%s" \
     CENTIPEDE_FORK_SERVER_FIFO1="%s" \
-    exec %s
+    %s
   } &
   printf "%%s" $! > "%s"
 )sh";
diff --git a/centipede/command_test.cc b/centipede/command_test.cc
index 4e638b4b..48f4d073 100644
--- a/centipede/command_test.cc
+++ b/centipede/command_test.cc
@@ -39,18 +39,18 @@ namespace {
 using ::testing::Optional;
 
 TEST(CommandTest, ToString) {
-  EXPECT_EQ(Command{"x"}.ToString(), "env \\\nx");
+  EXPECT_EQ(Command{"x"}.ToString(), "exec env \\\nx");
   {
     Command::Options cmd_options;
     cmd_options.args = {"arg1", "arg2"};
     EXPECT_EQ((Command{"path", std::move(cmd_options)}.ToString()),
-              "env \\\npath \\\narg1 \\\narg2");
+              "exec env \\\npath \\\narg1 \\\narg2");
   }
   {
     Command::Options cmd_options;
     cmd_options.env_diff = {"K1=V1", "K2=V2", "-K3"};
     EXPECT_EQ((Command{"x", std::move(cmd_options)}.ToString()),
-              "env \\\n-u K3 \\\nK1=V1 \\\nK2=V2 \\\nx");
+              "exec env \\\n-u K3 \\\nK1=V1 \\\nK2=V2 \\\nx");
   }
 }
 
@@ -80,7 +80,7 @@ TEST(CommandTest, InputFileWildCard) {
   Command::Options cmd_options;
   cmd_options.temp_file_path = "TEMP_FILE";
   Command cmd{"foo bar @@ baz", std::move(cmd_options)};
-  EXPECT_EQ(cmd.ToString(), "env \\\nfoo bar TEMP_FILE baz");
+  EXPECT_EQ(cmd.ToString(), "exec env \\\nfoo bar TEMP_FILE baz");
 }
 
 TEST(CommandTest, ForkServer) {