diff --git a/dbc.cpp b/dbc.cpp
index 13bafde..4653617 100644
--- a/dbc.cpp
+++ b/dbc.cpp
@@ -1,44 +1,47 @@
 #include "dbc.hpp"
 #include <iostream>
 
-void dbc::log(const string &message) {
-  std::cerr << "!!!!!!!!!!" << message << std::endl;
+void dbc::log(const string &message, const std::source_location location) {
+  std::clog << '[' << location.file_name() << ':'
+     << location.line() << "|"
+     << location.function_name() << "] "
+     << message << std::endl;
 }
 
-void dbc::sentinel(const string &message) {
+void dbc::sentinel(const string &message, const std::source_location location) {
   string err = fmt::format("[SENTINEL!] {}", message);
-  dbc::log(err);
+  dbc::log(err, location);
   throw dbc::SentinelError{err};
 }
 
-void dbc::pre(const string &message, bool test) {
+void dbc::pre(const string &message, bool test, const std::source_location location) {
   if(!test) {
     string err = fmt::format("[PRE!] {}", message);
-    dbc::log(err);
+    dbc::log(err, location);
     throw dbc::PreCondError{err};
   }
 }
 
-void dbc::pre(const string &message, std::function<bool()> tester) {
-  dbc::pre(message, tester());
+void dbc::pre(const string &message, std::function<bool()> tester, const std::source_location location) {
+  dbc::pre(message, tester(), location);
 }
 
-void dbc::post(const string &message, bool test) {
+void dbc::post(const string &message, bool test, const std::source_location location) {
   if(!test) {
     string err = fmt::format("[POST!] {}", message);
-    dbc::log(err);
+    dbc::log(err, location);
     throw dbc::PostCondError{err};
   }
 }
 
-void dbc::post(const string &message, std::function<bool()> tester) {
-  dbc::post(message, tester());
+void dbc::post(const string &message, std::function<bool()> tester, const std::source_location location) {
+  dbc::post(message, tester(), location);
 }
 
-void dbc::check(bool test, const string &message) {
+void dbc::check(bool test, const string &message, const std::source_location location) {
   if(!test) {
     string err = fmt::format("[CHECK!] {}\n", message);
-    dbc::log(err);
+    dbc::log(err, location);
     throw dbc::CheckError{err};
   }
 }
diff --git a/dbc.hpp b/dbc.hpp
index bb55122..87e4fb0 100644
--- a/dbc.hpp
+++ b/dbc.hpp
@@ -3,6 +3,7 @@
 #include <string>
 #include <fmt/core.h>
 #include <functional>
+#include <source_location>
 
 using std::string;
 
@@ -19,11 +20,31 @@ namespace dbc {
   class PreCondError : public Error {};
   class PostCondError : public Error {};
 
-  void log(const string &message);
-  [[noreturn]] void sentinel(const string &message);
-  void pre(const string &message, bool test);
-  void pre(const string &message, std::function<bool()> tester);
-  void post(const string &message, bool test);
-  void post(const string &message, std::function<bool()> tester);
-  void check(bool test, const string &message);
+  void log(const string &message,
+      const std::source_location location =
+      std::source_location::current());
+
+  [[noreturn]] void sentinel(const string &message,
+      const std::source_location location =
+      std::source_location::current());
+
+  void pre(const string &message, bool test,
+      const std::source_location location =
+      std::source_location::current());
+
+  void pre(const string &message, std::function<bool()> tester,
+      const std::source_location location =
+      std::source_location::current());
+
+  void post(const string &message, bool test,
+      const std::source_location location =
+      std::source_location::current());
+
+  void post(const string &message, std::function<bool()> tester,
+      const std::source_location location =
+      std::source_location::current());
+
+  void check(bool test, const string &message,
+      const std::source_location location =
+      std::source_location::current());
 }
diff --git a/tests/dbc.cpp b/tests/dbc.cpp
index 1d43905..5c7263d 100644
--- a/tests/dbc.cpp
+++ b/tests/dbc.cpp
@@ -3,12 +3,15 @@
 
 using namespace dbc;
 
-TEST_CASE("basic feature tests", "[utils]") {
+TEST_CASE("basic feature tests", "[dbc]") {
   log("Logging a message.");
 
   pre("confirm positive cases work", 1 == 1);
+
   pre("confirm positive lambda", [&]{ return 1 == 1;});
+
   post("confirm positive post", 1 == 1);
+
   post("confirm postitive post with lamdba", [&]{ return 1 == 1;});
 
   check(1 == 1, "one equals 1");