diff --git a/sources/auth.c b/sources/auth.c
index 4f8d27b5..a72e90b1 100644
--- a/sources/auth.c
+++ b/sources/auth.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/backend.c b/sources/backend.c
index a3ec8605..e4a57c9c 100644
--- a/sources/backend.c
+++ b/sources/backend.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/cancel.c b/sources/cancel.c
index 607c6bee..a6def6dd 100644
--- a/sources/cancel.c
+++ b/sources/cancel.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/client_pool.c b/sources/client_pool.c
index 1df76d20..33426dbd 100644
--- a/sources/client_pool.c
+++ b/sources/client_pool.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/config.c b/sources/config.c
index f34d5007..a6d02a02 100644
--- a/sources/config.c
+++ b/sources/config.c
@@ -23,6 +23,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/console.c b/sources/console.c
index 2512ce5c..8f1a73fc 100644
--- a/sources/console.c
+++ b/sources/console.c
@@ -19,6 +19,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/error.h b/sources/error.h
new file mode 100644
index 00000000..e6c91fcd
--- /dev/null
+++ b/sources/error.h
@@ -0,0 +1,67 @@
+#ifndef OD_ERROR_H
+#define OD_ERROR_H
+
+/*
+ * Odissey.
+ *
+ * Advanced PostgreSQL connection pooler.
+*/
+
+typedef struct od_error od_error_t;
+
+struct od_error
+{
+	char file[256];
+	int  file_len;
+	char function[128];
+	int  function_len;
+	char error[256];
+	int  error_len;
+	int  line;
+};
+
+static inline void
+od_error_init(od_error_t *error)
+{
+	error->file[0]      = 0;
+	error->file_len     = 0;
+	error->function[0]  = 0;
+	error->function_len = 0;
+	error->error[0]     = 0;
+	error->error_len    = 0;
+	error->line         = 0;
+}
+
+static inline void
+od_error_setv(od_error_t *error,
+              const char *file,
+              const char *function, int line,
+              char *fmt, va_list args)
+{
+	error->file_len =
+		snprintf(error->file, sizeof(error->file), "%s", file);
+	error->function_len =
+		snprintf(error->function, sizeof(error->function), "%s", function);
+	error->line = line;
+	int len;
+	len = vsnprintf(error->error, sizeof(error->error), fmt, args);
+	error->error_len = len;
+}
+
+static inline int
+od_error_set(od_error_t *error,
+             const char *file,
+             const char *function, int line,
+             char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	od_error_setv(error, file, function, line, fmt, args);
+	va_end(args);
+	return -1;
+}
+
+#define od_errorf(error, fmt, ...) \
+	od_error_set(error, __FILE__, __func__, __LINE__, fmt, __VA_ARGS__)
+
+#endif /* OD_ERROR_H */
diff --git a/sources/frontend.c b/sources/frontend.c
index 2e1de55a..ea111245 100644
--- a/sources/frontend.c
+++ b/sources/frontend.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/instance.c b/sources/instance.c
index 31dac8ea..579eeefa 100644
--- a/sources/instance.c
+++ b/sources/instance.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/periodic.c b/sources/periodic.c
index d8e59402..b0e05892 100644
--- a/sources/periodic.c
+++ b/sources/periodic.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/pooler.c b/sources/pooler.c
index 4c7d3dd0..b489c1a6 100644
--- a/sources/pooler.c
+++ b/sources/pooler.c
@@ -20,6 +20,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/relay.c b/sources/relay.c
index 988fb395..c0ade8d5 100644
--- a/sources/relay.c
+++ b/sources/relay.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/relay_pool.c b/sources/relay_pool.c
index cba8ebb3..f9640bb5 100644
--- a/sources/relay_pool.c
+++ b/sources/relay_pool.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/reset.c b/sources/reset.c
index d9c1b651..d8e6fd89 100644
--- a/sources/reset.c
+++ b/sources/reset.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/router.c b/sources/router.c
index e1e87791..e199bd17 100644
--- a/sources/router.c
+++ b/sources/router.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"
diff --git a/sources/scheme.c b/sources/scheme.c
index 680679af..895e64d4 100644
--- a/sources/scheme.c
+++ b/sources/scheme.c
@@ -15,6 +15,7 @@
 #include <machinarium.h>
 
 #include "sources/macro.h"
+#include "sources/error.h"
 #include "sources/list.h"
 #include "sources/pid.h"
 #include "sources/id.h"
diff --git a/sources/tls.c b/sources/tls.c
index 293a5ea5..74978aff 100644
--- a/sources/tls.c
+++ b/sources/tls.c
@@ -18,6 +18,7 @@
 
 #include "sources/macro.h"
 #include "sources/version.h"
+#include "sources/error.h"
 #include "sources/atomic.h"
 #include "sources/list.h"
 #include "sources/pid.h"