diff --git a/errors.go b/errors.go
new file mode 100644
index 0000000..e6741c7
--- /dev/null
+++ b/errors.go
@@ -0,0 +1,21 @@
+package eol
+
+import (
+	"sourcecode.social/reiver/go-erorr"
+)
+
+const (
+	errNilRuneScanner = erorr.Error("eol: nil rune-scanner")
+)
+
+func errNotEOL(r rune) error {
+	return erorr.Errorf("eol: %q (%U) is not an end-of-line character", r, r)
+}
+
+func errProblemReadingRune(err error, runeNumber uint64) error {
+	return erorr.Errorf("eol: problem reading rune №%d of end-of-line sequence: %w", runeNumber, err)
+}
+
+func errProblemUnreadingRune(err error, runeNumber uint64, r rune) error {
+	return erorr.Errorf("eol: problem unreading rune №%d (%q (%U)) of end-of-line sequence: %w", runeNumber, r, r, err)
+}