diff --git a/aoc.go b/aoc.go
index 8a1bee6..106d3c8 100644
--- a/aoc.go
+++ b/aoc.go
@@ -19,10 +19,10 @@ type AoC struct {
 
 func NewAoC(boardId, session string) (*AoC, error) {
 	if boardId == "" {
-		return nil, new(BoardIdRequiredError)
+		return nil, BoardIdRequiredError
 	}
 	if session == "" {
-		return nil, new(SessionRequiredError)
+		return nil, SessionRequiredError
 	}
 	return &AoC{
 		session: session,
@@ -31,6 +31,7 @@ func NewAoC(boardId, session string) (*AoC, error) {
 	}, nil
 }
 
+func (a *AoC) GetSession() string { return a.session }
 func (a *AoC) SetSession(session string) {
 	a.session = session
 	a.sessionErr = false
@@ -40,7 +41,7 @@ func (a *AoC) NeedsNewSession() bool { return a.sessionErr }
 func (a *AoC) SetCachedLeaderboard(l *Leaderboard) error {
 	yr, err := strconv.Atoi(l.Event)
 	if err != nil {
-		return new(InvalidYearError)
+		return InvalidYearError
 	}
 
 	a.boards[yr] = l
@@ -49,20 +50,20 @@ func (a *AoC) SetCachedLeaderboard(l *Leaderboard) error {
 
 func (a *AoC) GetCachedLeaderboard(year int) (*Leaderboard, error) {
 	if year < 2015 || year > time.Now().Year() {
-		return nil, new(InvalidYearError)
+		return nil, InvalidYearError
 	}
 	if board, ok := a.boards[year]; ok {
 		return board, nil
 	}
-	return nil, LeaderboardNotCachedError{year: year}
+	return nil, LeaderboardNotCachedError
 }
 
 func (a *AoC) GetLeaderboard(year int) (*Leaderboard, error) {
 	if year < 2015 || year > time.Now().Year() {
-		return nil, new(InvalidYearError)
+		return nil, InvalidYearError
 	}
 	if a.sessionErr {
-		return nil, new(SessionError)
+		return nil, SessionError
 	}
 	if board, ok := a.boards[year]; ok {
 		if time.Since(board.LastFetch) < (time.Minute * 15) {
@@ -74,7 +75,7 @@ func (a *AoC) GetLeaderboard(year int) (*Leaderboard, error) {
 	if err != nil {
 		if err.Error() == "invalid character '<' looking for beginning of value" {
 			a.sessionErr = true
-			return nil, new(SessionError)
+			return nil, SessionError
 		}
 		return nil, err
 	}
@@ -92,6 +93,9 @@ func (a *AoC) fetchLeaderboard(year int) (*Leaderboard, error) {
 	client := &http.Client{}
 	boardString := fmt.Sprintf("https://adventofcode.com/%d/leaderboard/private/view/%s.json", year, a.boardId)
 	req, err = http.NewRequest("GET", boardString, nil)
+	if err != nil {
+		return nil, err
+	}
 	req.Header.Add("Cookie", "session="+a.session)
 	resp, err = client.Do(req)
 	if err != nil {
@@ -103,9 +107,12 @@ func (a *AoC) fetchLeaderboard(year int) (*Leaderboard, error) {
 		return nil, err
 	}
 	strBody := string(body)
-	// strBody = strings.ReplaceAll(strBody, "\"last_star_ts\":\"0\"", "\"last_star_ts\":0")
 	err = json.Unmarshal([]byte(strBody), &leaderboard)
 	if err != nil {
+		if err.Error() == "invalid character '<' looking for beginning of value" {
+			a.sessionErr = true
+			return nil, SessionError
+		}
 		return nil, fmt.Errorf("error parsing board: %w", err)
 	}
 	for k, mbr := range leaderboard.Members {
diff --git a/aoc_errors.go b/aoc_errors.go
index b9cbd6c..c748b10 100644
--- a/aoc_errors.go
+++ b/aoc_errors.go
@@ -1,35 +1,13 @@
 package aoc
 
-import "fmt"
+import (
+	"errors"
+)
 
-type SessionRequiredError struct{}
-
-func (e SessionRequiredError) Error() string {
-	return "session key is required"
-}
-
-type SessionError struct{}
-
-func (e SessionError) Error() string {
-	return "invalid session"
-}
-
-type BoardIdRequiredError struct{}
-
-func (e BoardIdRequiredError) Error() string {
-	return "board id is required"
-}
-
-type InvalidYearError struct{}
-
-func (e InvalidYearError) Error() string {
-	return "invalid year"
-}
-
-type LeaderboardNotCachedError struct {
-	year int
-}
-
-func (e LeaderboardNotCachedError) Error() string {
-	return fmt.Sprintf("leaderboard (%d) is not cached", e.year)
-}
+var (
+	SessionRequiredError      = errors.New("session key is required")
+	SessionError              = errors.New("invalid session")
+	BoardIdRequiredError      = errors.New("board id is required")
+	InvalidYearError          = errors.New("invalid year")
+	LeaderboardNotCachedError = errors.New("leaderboard is not cached")
+)