diff --git a/client/global.go b/client/global.go
index cf90ad48a..7cbefa250 100644
--- a/client/global.go
+++ b/client/global.go
@@ -92,8 +92,8 @@ func GenIMEI() string {
 	randGen := rand.New(rand.NewSource(time.Now().UnixNano()))
 	for i := 0; i < 14; i++ { // generating all the base digits
 		toAdd := randGen.Intn(10)
-		fmt.Fprintf(&final, "%d", toAdd) // printing them here!
-		if (i+1)%2 == 0 {                // special proc for every 2nd one
+		final.WriteString(strconv.Itoa(toAdd))
+		if (i+1)%2 == 0 { // special proc for every 2nd one
 			toAdd *= 2
 			if toAdd >= 10 {
 				toAdd = (toAdd % 10) + 1
@@ -102,7 +102,7 @@ func GenIMEI() string {
 		sum += toAdd // and even add them here!
 	}
 	ctrlDigit := (sum * 9) % 10 // calculating the control digit
-	fmt.Fprintf(&final, "%d", ctrlDigit)
+	final.WriteString(strconv.Itoa(ctrlDigit))
 	return final.String()
 }
 
diff --git a/client/internal/auth/qimei.go b/client/internal/auth/qimei.go
index 5694330d7..627ca14c4 100644
--- a/client/internal/auth/qimei.go
+++ b/client/internal/auth/qimei.go
@@ -5,6 +5,7 @@ import (
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/md5"
+	crand "crypto/rand"
 	"crypto/rsa"
 	"crypto/x509"
 	"encoding/base64"
@@ -42,7 +43,7 @@ func (info *Device) RequestQImei() {
 
 	// init rsa key and aes key
 	publicKey := initPublicKey()
-	encryptedAesKey, _ := rsa.EncryptPKCS1v15(rand.New(rand.NewSource(time.Now().UnixNano())), publicKey, []byte(cryptKey))
+	encryptedAesKey, _ := rsa.EncryptPKCS1v15(crand.Reader, publicKey, []byte(cryptKey))
 
 	encryptedPayload := aesEncrypt(payload, []byte(cryptKey))
 
diff --git a/topic/feed.go b/topic/feed.go
index 56cd2f5a6..f48862d67 100644
--- a/topic/feed.go
+++ b/topic/feed.go
@@ -159,7 +159,7 @@ func DecodeFeed(p *channel.StFeed) *Feed {
 			f.Contents = append(f.Contents, &TextElement{Content: c.TextContent.Text.Unwrap()})
 		}
 		if c.EmojiContent != nil {
-			id, _ := strconv.ParseInt(c.EmojiContent.Id.Unwrap(), 10, 64)
+			id, _ := strconv.ParseInt(c.EmojiContent.Id.Unwrap(), 10, 32)
 			f.Contents = append(f.Contents, &EmojiElement{
 				Index: int32(id),
 				Id:    c.EmojiContent.Id.Unwrap(),