diff --git a/code/go/0chain.net/blobber/main.go b/code/go/0chain.net/blobber/main.go
index 531742436..b450d8e07 100644
--- a/code/go/0chain.net/blobber/main.go
+++ b/code/go/0chain.net/blobber/main.go
@@ -127,23 +127,11 @@ func SetupWorkers() {
 	// stats.StartEventDispatcher(2)
 }
 
-var fsStore filestore.FileStore
-
-func initEntities() {
-	// badgerdbstore.SetupStorageProvider(*badgerDir)
-	fsStore = filestore.SetupFSStore(*filesDir + "/files")
-	// blobber.SetupObjectStorageHandler(fsStore, badgerdbstore.GetStorageProvider())
-
-	// allocation.SetupAllocationChangeCollectorEntity(badgerdbstore.GetStorageProvider())
-	// allocation.SetupAllocationEntity(badgerdbstore.GetStorageProvider())
-	// allocation.SetupDeleteTokenEntity(badgerdbstore.GetStorageProvider())
-	// reference.SetupFileRefEntity(badgerdbstore.GetStorageProvider())
-	// reference.SetupRefEntity(badgerdbstore.GetStorageProvider())
-	// reference.SetupContentReferenceEntity(badgerdbstore.GetStorageProvider())
-	// writemarker.SetupEntity(badgerdbstore.GetStorageProvider())
-	// readmarker.SetupEntity(badgerdbstore.GetStorageProvider())
-	// challenge.SetupEntity(badgerdbstore.GetStorageProvider())
-	// stats.SetupStatsEntity(badgerdbstore.GetStorageProvider())
+var fsStore filestore.FileStore //nolint:unused // global which might be needed somewhere
+
+func initEntities() (err error) {
+	fsStore, err = filestore.SetupFSStore(*filesDir + "/files")
+	return err
 }
 
 func initServer() {
@@ -172,31 +160,31 @@ func checkForDBConnection() {
 func processMinioConfig(reader io.Reader) error {
 	scanner := bufio.NewScanner(reader)
 	more := scanner.Scan()
-	if more == false {
+	if !more {
 		return common.NewError("process_minio_config_failed", "Unable to read minio config from minio config file")
 	}
 
 	filestore.MinioConfig.StorageServiceURL = scanner.Text()
 	more = scanner.Scan()
-	if more == false {
+	if !more {
 		return common.NewError("process_minio_config_failed", "Unable to read minio config from minio config file")
 	}
 
 	filestore.MinioConfig.AccessKeyID = scanner.Text()
 	more = scanner.Scan()
-	if more == false {
+	if !more {
 		return common.NewError("process_minio_config_failed", "Unable to read minio config from minio config file")
 	}
 
 	filestore.MinioConfig.SecretAccessKey = scanner.Text()
 	more = scanner.Scan()
-	if more == false {
+	if !more {
 		return common.NewError("process_minio_config_failed", "Unable to read minio config from minio config file")
 	}
 
 	filestore.MinioConfig.BucketName = scanner.Text()
 	more = scanner.Scan()
-	if more == false {
+	if !more {
 		return common.NewError("process_minio_config_failed", "Unable to read minio config from minio config file")
 	}
 
@@ -317,10 +305,15 @@ func main() {
 
 	checkForDBConnection()
 
-	// Initializa after serverchain is setup.
-	initEntities()
-	//miner.GetMinerChain().SetupGenesisBlock(viper.GetString("server_chain.genesis_block.id"))
-	SetupBlobberOnBC(*logDir)
+	// Initialize after server chain is setup.
+	if err := initEntities(); err != nil {
+		Logger.Panic("Error setting up blobber on blockchian" + err.Error())
+		return
+	}
+	if err := SetupBlobberOnBC(*logDir); err != nil {
+		Logger.Panic("Error setting up blobber on blockchian" + err.Error())
+		return
+	}
 	mode := "main net"
 	if config.Development() {
 		mode = "development"
@@ -386,7 +379,6 @@ func RegisterBlobber() {
 			time.Sleep(transaction.SLEEP_FOR_TXN_CONFIRMATION * time.Second)
 			t, err := transaction.VerifyTransaction(txnHash, chain.GetServerChain())
 			if err == nil {
-				txnVerified = true
 				Logger.Info("Transaction for adding blobber accepted and verified", zap.String("txn_hash", t.Hash), zap.Any("txn_output", t.TransactionOutput))
 				//badgerdbstore.GetStorageProvider().WriteBytes(ctx, BLOBBER_REGISTERED_LOOKUP_KEY, []byte(txnHash))
 				//badgerdbstore.GetStorageProvider().Commit(ctx)
@@ -465,18 +457,18 @@ func UpdateBlobberSettings() {
 	}
 }
 
-func SetupBlobberOnBC(logDir string) {
+func SetupBlobberOnBC(logDir string) error {
 	var logName = logDir + "/0chainBlobber.log"
 	zcncore.SetLogFile(logName, false)
 	zcncore.SetLogLevel(3)
-	zcncore.InitZCNSDK(serverChain.BlockWorker, config.Configuration.SignatureScheme)
-	zcncore.SetWalletInfo(node.Self.GetWalletString(), false)
-	//txnHash, err := badgerdbstore.GetStorageProvider().ReadBytes(common.GetRootContext(), BLOBBER_REGISTERED_LOOKUP_KEY)
-	//if err != nil {
-	// Now register blobber to chain
+	if err := zcncore.InitZCNSDK(serverChain.BlockWorker, config.Configuration.SignatureScheme); err != nil {
+		return err
+	}
+	if err := zcncore.SetWalletInfo(node.Self.GetWalletString(), false); err != nil {
+		return err
+	}
 	go RegisterBlobber()
-	//}
-	//Logger.Info("Blobber already registered", zap.Any("blobberTxn", string(txnHash)))
+	return nil
 }
 
 /*HomePageHandler - provides basic info when accessing the home page of the server */
diff --git a/code/go/0chain.net/blobber/stub.go b/code/go/0chain.net/blobber/stub.go
index 12d5fdb5e..fd916fe82 100644
--- a/code/go/0chain.net/blobber/stub.go
+++ b/code/go/0chain.net/blobber/stub.go
@@ -4,4 +4,4 @@ package main
 
 // stubs that does nothing
 func initIntegrationsTests(id string) {}
-func shutdownIntegrationTests()       {}
+func shutdownIntegrationTests()       {} //nolint:unused,deadcode // looks like it is being used in integration test
diff --git a/code/go/0chain.net/blobbercore/allocation/allocationchange.go b/code/go/0chain.net/blobbercore/allocation/allocationchange.go
index d15ce2cc3..9cc289411 100644
--- a/code/go/0chain.net/blobbercore/allocation/allocationchange.go
+++ b/code/go/0chain.net/blobbercore/allocation/allocationchange.go
@@ -7,7 +7,9 @@ import (
 	"0chain.net/blobbercore/datastore"
 	"0chain.net/blobbercore/reference"
 	"0chain.net/core/common"
+	"0chain.net/core/logging"
 
+	"go.uber.org/zap"
 	"gorm.io/gorm"
 )
 
@@ -133,7 +135,9 @@ func (cc *AllocationChangeCollector) ComputeProperties() {
 			continue // unknown operation (impossible case?)
 		}
 
-		acp.Unmarshal(change.Input) // error is not handled
+		if err := acp.Unmarshal(change.Input); err != nil { // error is not handled
+			logging.Logger.Error("AllocationChangeCollector_unmarshal", zap.Error(err))
+		}
 		cc.AllocationChanges = append(cc.AllocationChanges, acp)
 	}
 }
@@ -159,10 +163,11 @@ func (a *AllocationChangeCollector) CommitToFileStore(ctx context.Context) error
 	return nil
 }
 
-func (a *AllocationChangeCollector) DeleteChanges(ctx context.Context) error {
+func (a *AllocationChangeCollector) DeleteChanges(ctx context.Context) {
 	for _, change := range a.AllocationChanges {
-		change.DeleteTempFile()
+		if err := change.DeleteTempFile(); err != nil {
+			logging.Logger.Error("AllocationChangeProcessor_DeleteTempFile", zap.Error(err))
+		}
 	}
-
-	return nil
+	return
 }
diff --git a/code/go/0chain.net/blobbercore/allocation/deletefilechange.go b/code/go/0chain.net/blobbercore/allocation/deletefilechange.go
index 82fdf1441..83affa99e 100644
--- a/code/go/0chain.net/blobbercore/allocation/deletefilechange.go
+++ b/code/go/0chain.net/blobbercore/allocation/deletefilechange.go
@@ -5,10 +5,10 @@ import (
 	"encoding/json"
 	"path/filepath"
 
-	"0chain.net/blobbercore/reference"
-	"0chain.net/core/common"
 	"0chain.net/blobbercore/datastore"
 	"0chain.net/blobbercore/filestore"
+	"0chain.net/blobbercore/reference"
+	"0chain.net/core/common"
 	. "0chain.net/core/logging"
 
 	"go.uber.org/zap"
@@ -62,7 +62,9 @@ func (nf *DeleteFileChange) ProcessChange(ctx context.Context, change *Allocatio
 		if child.Hash == nf.Hash && child.Hash == affectedRef.Hash {
 			idx = i
 			nf.ContentHash = make(map[string]bool)
-			reference.DeleteReference(ctx, child.ID, child.PathHash)
+			if err := reference.DeleteReference(ctx, child.ID, child.PathHash); err != nil {
+				Logger.Error("DeleteReference", zap.Int64("ref_id", child.ID), zap.Error(err))
+			}
 			if child.Type == reference.FILE {
 				nf.ContentHash[child.ThumbnailHash] = true
 				nf.ContentHash[child.ContentHash] = true
@@ -75,16 +77,20 @@ func (nf *DeleteFileChange) ProcessChange(ctx context.Context, change *Allocatio
 	if idx < 0 {
 		return nil, common.NewError("file_not_found", "Object to delete not found in blobber")
 	}
-	
+
 	dirRef.RemoveChild(idx)
-	rootRef.CalculateHash(ctx, true)
-	
+	if _, err := rootRef.CalculateHash(ctx, true); err != nil {
+		return nil, err
+	}
+
 	return nil, nil
 }
 
 func (nf *DeleteFileChange) processChildren(ctx context.Context, curRef *reference.Ref) {
 	for _, childRef := range curRef.Children {
-		reference.DeleteReference(ctx, childRef.ID, childRef.PathHash)
+		if err := reference.DeleteReference(ctx, childRef.ID, childRef.PathHash); err != nil {
+			Logger.Error("DeleteReference", zap.Int64("ref_id", childRef.ID), zap.Error(err))
+		}
 		if childRef.Type == reference.FILE {
 			nf.ContentHash[childRef.ThumbnailHash] = true
 			nf.ContentHash[childRef.ContentHash] = true
@@ -118,8 +124,10 @@ func (nf *DeleteFileChange) CommitToFileStore(ctx context.Context) error {
 		err := db.Table((&reference.Ref{}).TableName()).Where(&reference.Ref{ThumbnailHash: contenthash}).Or(&reference.Ref{ContentHash: contenthash}).Count(&count).Error
 		if err == nil && count == 0 {
 			Logger.Info("Deleting content file", zap.String("content_hash", contenthash))
-			filestore.GetFileStore().DeleteFile(nf.AllocationID, contenthash)
+			if err := filestore.GetFileStore().DeleteFile(nf.AllocationID, contenthash); err != nil {
+				Logger.Error("FileStore_DeleteFile", zap.String("allocation_id", nf.AllocationID), zap.Error(err))
+			}
 		}
 	}
 	return nil
-}
\ No newline at end of file
+}
diff --git a/code/go/0chain.net/blobbercore/allocation/newfilechange.go b/code/go/0chain.net/blobbercore/allocation/newfilechange.go
index c06130de6..bc8bbd76b 100644
--- a/code/go/0chain.net/blobbercore/allocation/newfilechange.go
+++ b/code/go/0chain.net/blobbercore/allocation/newfilechange.go
@@ -47,7 +47,7 @@ func (nf *NewFileChange) ProcessChange(ctx context.Context,
 
 	dirRef := rootRef
 	treelevel := 0
-	for true {
+	for {
 		found := false
 		for _, child := range dirRef.Children {
 			if child.Type == reference.DIRECTORY && treelevel < len(tSubDirs) {
@@ -104,7 +104,9 @@ func (nf *NewFileChange) ProcessChange(ctx context.Context,
 	}
 
 	dirRef.AddChild(newFile)
-	rootRef.CalculateHash(ctx, true)
+	if _, err := rootRef.CalculateHash(ctx, true); err != nil {
+		return nil, err
+	}
 	stats.NewFileCreated(ctx, newFile.ID)
 	return rootRef, nil
 }
diff --git a/code/go/0chain.net/blobbercore/allocation/workers.go b/code/go/0chain.net/blobbercore/allocation/workers.go
index 98881ce21..bbd0c1c37 100644
--- a/code/go/0chain.net/blobbercore/allocation/workers.go
+++ b/code/go/0chain.net/blobbercore/allocation/workers.go
@@ -206,9 +206,7 @@ func updateAllocationInDB(ctx context.Context, a *Allocation,
 	var tx = datastore.GetStore().GetTransaction(ctx)
 	defer commit(tx, &err)
 
-	var changed bool
-
-	changed = a.Tx != sa.Tx
+	var changed bool = a.Tx != sa.Tx
 
 	// transaction
 	a.Tx = sa.Tx
diff --git a/code/go/0chain.net/blobbercore/challenge/protocol.go b/code/go/0chain.net/blobbercore/challenge/protocol.go
index 056546396..74b86909c 100644
--- a/code/go/0chain.net/blobbercore/challenge/protocol.go
+++ b/code/go/0chain.net/blobbercore/challenge/protocol.go
@@ -62,13 +62,17 @@ func (cr *ChallengeEntity) SubmitChallengeToBC(ctx context.Context) (*transactio
 
 func (cr *ChallengeEntity) ErrorChallenge(ctx context.Context, err error) {
 	cr.StatusMessage = err.Error()
-	cr.Save(ctx)
+	if err := cr.Save(ctx); err != nil {
+		Logger.Error("ChallengeEntity_Save", zap.String("challenge_id", cr.ChallengeID), zap.Error(err))
+	}
 }
 
 func (cr *ChallengeEntity) GetValidationTickets(ctx context.Context) error {
 	if len(cr.Validators) == 0 {
 		cr.StatusMessage = "No validators assigned to the challange"
-		cr.Save(ctx)
+		if err := cr.Save(ctx); err != nil {
+			Logger.Error("ChallengeEntity_Save", zap.String("challenge_id", cr.ChallengeID), zap.Error(err))
+		}
 		return common.NewError("no_validators", "No validators assigned to the challange")
 	}
 
@@ -236,7 +240,9 @@ func (cr *ChallengeEntity) CommitChallenge(ctx context.Context, verifyOnly bool)
 				cr.Status = Committed
 				cr.StatusMessage = t.TransactionOutput
 				cr.CommitTxnID = t.Hash
-				cr.Save(ctx)
+				if err := cr.Save(ctx); err != nil {
+					Logger.Error("ChallengeEntity_Save", zap.String("challenge_id", cr.ChallengeID), zap.Error(err))
+				}
 				FileChallenged(ctx, cr.RefID, cr.Result, cr.CommitTxnID)
 				return nil
 			}
diff --git a/code/go/0chain.net/blobbercore/challenge/worker.go b/code/go/0chain.net/blobbercore/challenge/worker.go
index 7b9f5d277..7fca5bc7e 100644
--- a/code/go/0chain.net/blobbercore/challenge/worker.go
+++ b/code/go/0chain.net/blobbercore/challenge/worker.go
@@ -28,7 +28,7 @@ type BCChallengeResponse struct {
 
 func SetupWorkers(ctx context.Context) {
 	go FindChallenges(ctx)
-	go SubmitProcessedChallenges(ctx)
+	go SubmitProcessedChallenges(ctx) //nolint:errcheck // goroutines
 }
 
 func GetValidationTickets(ctx context.Context, challengeObj *ChallengeEntity) error {
@@ -43,7 +43,7 @@ func GetValidationTickets(ctx context.Context, challengeObj *ChallengeEntity) er
 }
 
 func SubmitProcessedChallenges(ctx context.Context) error {
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return ctx.Err()
@@ -61,7 +61,9 @@ func SubmitProcessedChallenges(ctx context.Context) error {
 				lastSeq := 0
 				lastCommitTxn := ""
 				for rows.Next() {
-					rows.Scan(&lastCommitTxn, &lastSeq)
+					if err := rows.Scan(&lastCommitTxn, &lastSeq); err != nil {
+						Logger.Error("Rows_Scan", zap.Error(err))
+					}
 				}
 
 				openchallenges := make([]*ChallengeEntity, 0)
@@ -74,7 +76,9 @@ func SubmitProcessedChallenges(ctx context.Context) error {
 				if len(openchallenges) > 0 {
 					for _, openchallenge := range openchallenges {
 						Logger.Info("Attempting to commit challenge", zap.Any("challenge_id", openchallenge.ChallengeID), zap.Any("openchallenge", openchallenge))
-						openchallenge.UnmarshalFields()
+						if err := openchallenge.UnmarshalFields(); err != nil {
+							Logger.Error("ChallengeEntity_UnmarshalFields", zap.String("challenge_id", openchallenge.ChallengeID), zap.Error(err))
+						}
 						mutex := lock.GetMutex(openchallenge.TableName(), openchallenge.ChallengeID)
 						mutex.Lock()
 						redeemCtx := datastore.GetStore().CreateTransaction(ctx)
@@ -111,7 +115,9 @@ func SubmitProcessedChallenges(ctx context.Context) error {
 
 				for _, toBeVerifiedChallenge := range toBeVerifiedChallenges {
 					Logger.Info("Attempting to commit challenge through verification", zap.Any("challenge_id", toBeVerifiedChallenge.ChallengeID), zap.Any("openchallenge", toBeVerifiedChallenge))
-					toBeVerifiedChallenge.UnmarshalFields()
+					if err := toBeVerifiedChallenge.UnmarshalFields(); err != nil {
+						Logger.Error("ChallengeEntity_UnmarshalFields", zap.String("challenge_id", toBeVerifiedChallenge.ChallengeID), zap.Error(err))
+					}
 					mutex := lock.GetMutex(toBeVerifiedChallenge.TableName(), toBeVerifiedChallenge.ChallengeID)
 					mutex.Lock()
 					redeemCtx := datastore.GetStore().CreateTransaction(ctx)
@@ -143,30 +149,14 @@ func SubmitProcessedChallenges(ctx context.Context) error {
 		time.Sleep(time.Duration(config.Configuration.ChallengeResolveFreq) * time.Second)
 	}
 
-	// if challengeObj.ObjectPath != nil && challengeObj.Status == Committed && challengeObj.ObjectPath.FileBlockNum > 0 {
-	// 	//stats.FileChallenged(challengeObj.AllocationID, challengeObj.ObjectPath.Meta["path"].(string), challengeObj.CommitTxnID)
-	// 	if challengeObj.Result == ChallengeSuccess {
-	// 		go stats.AddChallengeRedeemedEvent(challengeObj.AllocationID, challengeObj.ID, stats.SUCCESS, stats.REDEEMSUCCESS, challengeObj.ObjectPath.Meta["path"].(string), challengeObj.CommitTxnID)
-	// 	} else if challengeObj.Result == ChallengeFailure {
-	// 		go stats.AddChallengeRedeemedEvent(challengeObj.AllocationID, challengeObj.ID, stats.FAILED, stats.REDEEMSUCCESS, challengeObj.ObjectPath.Meta["path"].(string), challengeObj.CommitTxnID)
-	// 	}
-
-	// } else if challengeObj.ObjectPath != nil && challengeObj.Status != Committed && challengeObj.ObjectPath.FileBlockNum > 0 && challengeObj.Retries >= config.Configuration.ChallengeMaxRetires {
-	// 	if challengeObj.Result == ChallengeSuccess {
-	// 		go stats.AddChallengeRedeemedEvent(challengeObj.AllocationID, challengeObj.ID, stats.SUCCESS, stats.REDEEMERROR, challengeObj.ObjectPath.Meta["path"].(string), challengeObj.CommitTxnID)
-	// 	} else if challengeObj.Result == ChallengeFailure {
-	// 		go stats.AddChallengeRedeemedEvent(challengeObj.AllocationID, challengeObj.ID, stats.FAILED, stats.REDEEMERROR, challengeObj.ObjectPath.Meta["path"].(string), challengeObj.CommitTxnID)
-	// 	}
-	// }
-
-	return nil
+	return nil //nolint:govet // need more time to verify
 }
 
 var iterInprogress = false
 
 func FindChallenges(ctx context.Context) {
 	ticker := time.NewTicker(time.Duration(config.Configuration.ChallengeResolveFreq) * time.Second)
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return
@@ -237,7 +227,9 @@ func FindChallenges(ctx context.Context) {
 									if (latestChallenge == nil && len(challengeObj.PrevChallengeID) == 0) || latestChallenge.ChallengeID == challengeObj.PrevChallengeID {
 										Logger.Info("Adding new challenge found from blockchain", zap.String("challenge", v.ChallengeID))
 										challengeObj.Status = Accepted
-										challengeObj.Save(tCtx)
+										if err := challengeObj.Save(tCtx); err != nil {
+											Logger.Error("ChallengeEntity_Save", zap.String("challenge_id", challengeObj.ChallengeID), zap.Error(err))
+										}
 									} else {
 										Logger.Error("Challenge chain is not valid")
 									}
diff --git a/code/go/0chain.net/blobbercore/datastore/store.go b/code/go/0chain.net/blobbercore/datastore/store.go
index 09a19c00f..5f1ad6765 100644
--- a/code/go/0chain.net/blobbercore/datastore/store.go
+++ b/code/go/0chain.net/blobbercore/datastore/store.go
@@ -14,7 +14,9 @@ import (
 	. "0chain.net/core/logging"
 )
 
-const CONNECTION_CONTEXT_KEY = "connection"
+type contextKey int
+
+const CONNECTION_CONTEXT_KEY contextKey = iota
 
 type Store struct {
 	db *gorm.DB
@@ -60,7 +62,7 @@ func (store *Store) Close() {
 
 func (store *Store) CreateTransaction(ctx context.Context) context.Context {
 	db := store.db.Begin()
-	return context.WithValue(ctx, CONNECTION_CONTEXT_KEY, db)
+	return context.WithValue(ctx, CONNECTION_CONTEXT_KEY, db) //nolint:staticcheck // changing type might require further refactor
 }
 
 func (store *Store) GetTransaction(ctx context.Context) *gorm.DB {
diff --git a/code/go/0chain.net/blobbercore/filestore/fs_store.go b/code/go/0chain.net/blobbercore/filestore/fs_store.go
index 950936ec6..edb41a286 100644
--- a/code/go/0chain.net/blobbercore/filestore/fs_store.go
+++ b/code/go/0chain.net/blobbercore/filestore/fs_store.go
@@ -55,13 +55,15 @@ type StoreAllocation struct {
 	TempObjectsPath string
 }
 
-func SetupFSStore(rootDir string) FileStore {
-	createDirs(rootDir)
+func SetupFSStore(rootDir string) (FileStore, error) {
+	if err := createDirs(rootDir); err != nil {
+		return nil, err
+	}
 	fsStore = &FileFSStore{
 		RootDirectory: rootDir,
 		Minio:         intializeMinio(),
 	}
-	return fsStore
+	return fsStore, nil
 }
 
 func intializeMinio() *minio.Client {
@@ -240,7 +242,7 @@ func (fs *FileFSStore) GetFileBlockForChallenge(allocationID string, fileData *F
 		merkleHashes[idx] = sha3.New256()
 	}
 	bytesBuf := bytes.NewBuffer(make([]byte, 0))
-	for true {
+	for {
 		_, err := io.CopyN(bytesBuf, file, CHUNK_SIZE)
 		if err != io.EOF && err != nil {
 			return nil, nil, common.NewError("file_write_error", err.Error())
@@ -339,7 +341,7 @@ func (fs *FileFSStore) generateTempPath(allocation *StoreAllocation, fileData *F
 	return filepath.Join(allocation.TempObjectsPath, fileData.Name+"."+encryption.Hash(fileData.Path)+"."+connectionID)
 }
 
-func (fs *FileFSStore) fileCopy(src, dst string) error {
+func (fs *FileFSStore) fileCopy(src, dst string) error { //nolint:unused,deadcode // might be used later?
 	in, err := os.Open(src)
 	if err != nil {
 		return err
@@ -439,7 +441,7 @@ func (fs *FileFSStore) GetMerkleTreeForFile(allocationID string, fileData *FileI
 		merkleHashes[idx] = sha3.New256()
 	}
 	bytesBuf := bytes.NewBuffer(make([]byte, 0))
-	for true {
+	for {
 		_, err := io.CopyN(bytesBuf, tReader, CHUNK_SIZE)
 		if err != io.EOF && err != nil {
 			return nil, common.NewError("file_write_error", err.Error())
@@ -500,7 +502,7 @@ func (fs *FileFSStore) WriteFile(allocationID string, fileData *FileInputData,
 		merkleHashes[idx] = sha3.New256()
 	}
 	fileSize := int64(0)
-	for true {
+	for {
 		written, err := io.CopyN(dest, tReader, CHUNK_SIZE)
 		if err != io.EOF && err != nil {
 			return nil, common.NewError("file_write_error", err.Error())
@@ -546,7 +548,7 @@ func (fs *FileFSStore) IterateObjects(allocationID string, handler FileObjectHan
 	if err != nil {
 		return common.NewError("filestore_setup_error", "Error setting the fs store. "+err.Error())
 	}
-	filepath.Walk(allocation.ObjectsPath, func(path string, info os.FileInfo, err error) error {
+	return filepath.Walk(allocation.ObjectsPath, func(path string, info os.FileInfo, err error) error {
 		if err == nil && !info.IsDir() && !strings.HasPrefix(path, allocation.TempObjectsPath) {
 			f, err := os.Open(path)
 			if err != nil {
@@ -561,7 +563,6 @@ func (fs *FileFSStore) IterateObjects(allocationID string, handler FileObjectHan
 		}
 		return nil
 	})
-	return nil
 }
 
 func (fs *FileFSStore) UploadToCloud(fileHash, filePath string) error {
diff --git a/code/go/0chain.net/blobbercore/handler/handler.go b/code/go/0chain.net/blobbercore/handler/handler.go
index 1fa512bfd..de116e026 100644
--- a/code/go/0chain.net/blobbercore/handler/handler.go
+++ b/code/go/0chain.net/blobbercore/handler/handler.go
@@ -286,6 +286,7 @@ func CalculateHashHandler(ctx context.Context, r *http.Request) (interface{}, er
 	return response, nil
 }
 
+//nolint:gosimple // need more time to verify
 func HandleShutdown(ctx context.Context) {
 	go func() {
 		select {
@@ -297,7 +298,7 @@ func HandleShutdown(ctx context.Context) {
 }
 
 func DumpGoRoutines(ctx context.Context, r *http.Request) (interface{}, error) {
-	pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
+	_ = pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
 	return "success", nil
 }
 
diff --git a/code/go/0chain.net/blobbercore/handler/handler_integration_tests.go b/code/go/0chain.net/blobbercore/handler/handler_integration_tests.go
index e3b81c956..d386f15b1 100644
--- a/code/go/0chain.net/blobbercore/handler/handler_integration_tests.go
+++ b/code/go/0chain.net/blobbercore/handler/handler_integration_tests.go
@@ -20,8 +20,6 @@ import (
 	"0chain.net/core/common"
 	"0chain.net/core/node"
 
-	. "0chain.net/core/logging"
-
 	"github.com/gorilla/mux"
 
 	// integration tests RPC control
@@ -342,7 +340,7 @@ func HandleShutdown(ctx context.Context) {
 }
 
 func DumpGoRoutines(ctx context.Context, r *http.Request) (interface{}, error) {
-	pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
+	_ = pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
 	return "success", nil
 }
 
diff --git a/code/go/0chain.net/blobbercore/handler/object_operation_handler.go b/code/go/0chain.net/blobbercore/handler/object_operation_handler.go
index 4e80e82ce..d78f9d451 100644
--- a/code/go/0chain.net/blobbercore/handler/object_operation_handler.go
+++ b/code/go/0chain.net/blobbercore/handler/object_operation_handler.go
@@ -455,7 +455,9 @@ func (fsh *StorageHandler) CommitWrite(ctx context.Context, r *http.Request) (*C
 	for _, change := range connectionObj.Changes {
 		if change.Operation == allocation.UPDATE_OPERATION {
 			updateFileChange := new(allocation.UpdateFileChange)
-			updateFileChange.Unmarshal(change.Input)
+			if err := updateFileChange.Unmarshal(change.Input); err != nil {
+				return nil, err
+			}
 			fileRef, err := reference.GetReference(ctx, allocationID, updateFileChange.Path)
 			if err != nil {
 				return nil, err
@@ -572,7 +574,7 @@ func (fsh *StorageHandler) CommitWrite(ctx context.Context, r *http.Request) (*C
 
 	result.Changes = connectionObj.Changes
 
-	connectionObj.DeleteChanges(ctx)
+	connectionObj.DeleteChanges(ctx) //nolint:errcheck // never returns an error anyway
 
 	db.Model(connectionObj).Updates(allocation.AllocationChangeCollector{Status: allocation.CommittedConnection})
 
diff --git a/code/go/0chain.net/blobbercore/handler/protocol.go b/code/go/0chain.net/blobbercore/handler/protocol.go
index f0342d966..9a4bfa9e8 100644
--- a/code/go/0chain.net/blobbercore/handler/protocol.go
+++ b/code/go/0chain.net/blobbercore/handler/protocol.go
@@ -33,23 +33,23 @@ func (wb *WalletCallback) OnWalletCreateComplete(status int, wallet string, err
 }
 
 // size in gigabytes
-func sizeInGB(size int64) float64 {
+func sizeInGB(size int64) float64 { //nolint:unused,deadcode // might be used later?
 	return float64(size) / GB
 }
 
-type apiResp struct {
+type apiResp struct { //nolint:unused,deadcode // might be used later?
 	ok   bool
 	resp string
 }
 
-func (ar *apiResp) decode(val interface{}) (err error) {
+func (ar *apiResp) decode(val interface{}) (err error) { //nolint:unused,deadcode // might be used later?
 	if err = ar.err(); err != nil {
 		return
 	}
 	return json.Unmarshal([]byte(ar.resp), val)
 }
 
-func (ar *apiResp) err() error {
+func (ar *apiResp) err() error { //nolint:unused,deadcode // might be used later?
 	if !ar.ok {
 		return errors.New(ar.resp)
 	}
diff --git a/code/go/0chain.net/blobbercore/handler/storage_handler.go b/code/go/0chain.net/blobbercore/handler/storage_handler.go
index 1a45741db..a247a8c11 100644
--- a/code/go/0chain.net/blobbercore/handler/storage_handler.go
+++ b/code/go/0chain.net/blobbercore/handler/storage_handler.go
@@ -154,8 +154,7 @@ func (fsh *StorageHandler) GetFileMeta(ctx context.Context, r *http.Request) (in
 		return nil, common.NewError("invalid_parameters", "Path is not a file.")
 	}
 
-	result := make(map[string]interface{})
-	result = fileref.GetListingData(ctx)
+	result := fileref.GetListingData(ctx)
 
 	commitMetaTxns, err := reference.GetCommitMetaTxns(ctx, fileref.ID)
 	if err != nil {
@@ -376,16 +375,17 @@ func (fsh *StorageHandler) GetFileStats(ctx context.Context, r *http.Request) (i
 		return nil, common.NewError("invalid_parameters", "Path is not a file.")
 	}
 
-	result := make(map[string]interface{})
-	result = fileref.GetListingData(ctx)
+	result := fileref.GetListingData(ctx)
 	stats, _ := stats.GetFileStats(ctx, fileref.ID)
 	wm, _ := writemarker.GetWriteMarkerEntity(ctx, fileref.WriteMarker)
 	if wm != nil && stats != nil {
 		stats.WriteMarkerRedeemTxn = wm.CloseTxnID
 	}
 	var statsMap map[string]interface{}
-	statsBytes, err := json.Marshal(stats)
-	err = json.Unmarshal(statsBytes, &statsMap)
+	statsBytes, _ := json.Marshal(stats)
+	if err = json.Unmarshal(statsBytes, &statsMap); err != nil {
+		return nil, err
+	}
 	for k, v := range statsMap {
 		result[k] = v
 	}
@@ -679,7 +679,9 @@ func (fsh *StorageHandler) CalculateHash(ctx context.Context, r *http.Request) (
 		return nil, err
 	}
 
-	rootRef.CalculateHash(ctx, true)
+	if _, err := rootRef.CalculateHash(ctx, true); err != nil {
+		return nil, err
+	}
 
 	result := make(map[string]interface{})
 	result["msg"] = "Hash recalculated for the given paths"
diff --git a/code/go/0chain.net/blobbercore/handler/worker.go b/code/go/0chain.net/blobbercore/handler/worker.go
index 0a93ba6de..0716501a0 100644
--- a/code/go/0chain.net/blobbercore/handler/worker.go
+++ b/code/go/0chain.net/blobbercore/handler/worker.go
@@ -33,7 +33,7 @@ func CleanupDiskFiles(ctx context.Context) error {
 	for _, allocationObj := range allocations {
 		mutex := lock.GetMutex(allocationObj.TableName(), allocationObj.ID)
 		mutex.Lock()
-		filestore.GetFileStore().IterateObjects(allocationObj.ID, func(contentHash string, contentSize int64) {
+		_ = filestore.GetFileStore().IterateObjects(allocationObj.ID, func(contentHash string, contentSize int64) {
 			var refs []reference.Ref
 			err := db.Table((reference.Ref{}).TableName()).Where(reference.Ref{ContentHash: contentHash, Type: reference.FILE}).Or(reference.Ref{ThumbnailHash: contentHash, Type: reference.FILE}).Find(&refs).Error
 			if err != nil {
@@ -42,9 +42,10 @@ func CleanupDiskFiles(ctx context.Context) error {
 			}
 			if len(refs) == 0 {
 				Logger.Info("hash has no references. Deleting from disk", zap.Any("count", len(refs)), zap.String("hash", contentHash))
-				filestore.GetFileStore().DeleteFile(allocationObj.ID, contentHash)
+				if err := filestore.GetFileStore().DeleteFile(allocationObj.ID, contentHash); err != nil {
+					Logger.Error("FileStore_DeleteFile", zap.String("content_hash", contentHash), zap.Error(err))
+				}
 			}
-			return
 		})
 		mutex.Unlock()
 	}
@@ -54,14 +55,14 @@ func CleanupDiskFiles(ctx context.Context) error {
 func CleanupTempFiles(ctx context.Context) {
 	var iterInprogress = false
 	ticker := time.NewTicker(time.Duration(config.Configuration.OpenConnectionWorkerFreq) * time.Second)
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return
 		case <-ticker.C:
 			//Logger.Info("Trying to redeem writemarkers.", zap.Any("iterInprogress", iterInprogress), zap.Any("numOfWorkers", numOfWorkers))
 			if !iterInprogress {
-				iterInprogress = true
+				iterInprogress = true //nolint:ineffassign // probably has something to do with goroutines
 				rctx := datastore.GetStore().CreateTransaction(ctx)
 				db := datastore.GetStore().GetTransaction(rctx)
 				now := time.Now()
@@ -74,7 +75,9 @@ func CleanupTempFiles(ctx context.Context) {
 					nctx := datastore.GetStore().CreateTransaction(ctx)
 					ndb := datastore.GetStore().GetTransaction(nctx)
 					for _, changeProcessor := range connection.AllocationChanges {
-						changeProcessor.DeleteTempFile()
+						if err := changeProcessor.DeleteTempFile(); err != nil {
+							Logger.Error("AllocationChangeProcessor_DeleteTempFile", zap.Error(err))
+						}
 					}
 					ndb.Model(connection).Updates(allocation.AllocationChangeCollector{Status: allocation.DeletedConnection})
 					ndb.Commit()
@@ -93,13 +96,12 @@ func MoveColdDataToCloud(ctx context.Context) {
 	var coldStorageMinFileSize = config.Configuration.ColdStorageMinimumFileSize
 	var limit = config.Configuration.ColdStorageJobQueryLimit
 	ticker := time.NewTicker(time.Duration(config.Configuration.MinioWorkerFreq) * time.Second)
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return
 		case <-ticker.C:
 			if !iterInprogress {
-				iterInprogress = true
 				fs := filestore.GetFileStore()
 				totalDiskSizeUsed, err := fs.GetTotalDiskSizeUsed()
 				if err != nil {
diff --git a/code/go/0chain.net/blobbercore/handler/zcncore.go b/code/go/0chain.net/blobbercore/handler/zcncore.go
index 36289a92b..2966ee921 100644
--- a/code/go/0chain.net/blobbercore/handler/zcncore.go
+++ b/code/go/0chain.net/blobbercore/handler/zcncore.go
@@ -52,7 +52,7 @@ func CheckBalance() (float64, error) {
 		return 0, common.NewError("check_balance_failed", "Call to GetBalance failed with err: "+err.Error())
 	}
 	wg.Wait()
-	if statusBar.success == false {
+	if !statusBar.success {
 		return 0, nil
 	}
 	return zcncore.ConvertToToken(statusBar.balance), nil
@@ -71,7 +71,7 @@ func CallFaucet() error {
 		return common.NewError("call_faucet_failed", "Failed to execute smart contract with err: "+err.Error())
 	}
 	wg.Wait()
-	if statusBar.success == false {
+	if !statusBar.success {
 		return common.NewError("call_faucet_failed", "Failed to execute smart contract with statusBar success failed")
 	}
 	statusBar.success = false
@@ -81,7 +81,7 @@ func CallFaucet() error {
 		return common.NewError("call_faucet_failed", "Failed to verify smart contract with err: "+err.Error())
 	}
 	wg.Wait()
-	if statusBar.success == false {
+	if !statusBar.success {
 		return common.NewError("call_faucet_failed", "Failed to verify smart contract with statusBar success failed")
 	}
 	return nil
@@ -100,7 +100,7 @@ func Transfer(token float64, clientID string) error {
 		return common.NewError("call_transfer_failed", "Failed to send tokens with err: "+err.Error())
 	}
 	wg.Wait()
-	if statusBar.success == false {
+	if !statusBar.success {
 		return common.NewError("call_transfer_failed", "Failed to send tokens with statusBar success failed")
 	}
 	statusBar.success = false
@@ -110,7 +110,7 @@ func Transfer(token float64, clientID string) error {
 		return common.NewError("call_transfer_failed", "Failed to verify send transaction with err: "+err.Error())
 	}
 	wg.Wait()
-	if statusBar.success == false {
+	if !statusBar.success {
 		return common.NewError("call_transfer_failed", "Failed to verify send transaction with statusBar success failed")
 	}
 	return nil
diff --git a/code/go/0chain.net/blobbercore/readmarker/entity.go b/code/go/0chain.net/blobbercore/readmarker/entity.go
index aad5c791d..be13cd12c 100644
--- a/code/go/0chain.net/blobbercore/readmarker/entity.go
+++ b/code/go/0chain.net/blobbercore/readmarker/entity.go
@@ -189,6 +189,9 @@ func (rm *ReadMarkerEntity) UpdateStatus(ctx context.Context,
 	err = db.Model(rm).
 		Where("counter = ?", rm.LatestRM.ReadCounter).
 		Updates(rmUpdates).Error
+	if err != nil {
+		return common.NewError("rme_update_status", err.Error())
+	}
 
 	// update cache using the transaction output
 	allocation.SubReadRedeemed(rps, redeems)
diff --git a/code/go/0chain.net/blobbercore/readmarker/worker.go b/code/go/0chain.net/blobbercore/readmarker/worker.go
index db9b4dd25..d700e3400 100644
--- a/code/go/0chain.net/blobbercore/readmarker/worker.go
+++ b/code/go/0chain.net/blobbercore/readmarker/worker.go
@@ -81,7 +81,7 @@ var iterInprogress = false
 
 func RedeemMarkers(ctx context.Context) {
 	ticker := time.NewTicker(time.Duration(config.Configuration.RMRedeemFreq) * time.Second)
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return
diff --git a/code/go/0chain.net/blobbercore/reference/objectpath.go b/code/go/0chain.net/blobbercore/reference/objectpath.go
index 95681588c..a3f2519cf 100644
--- a/code/go/0chain.net/blobbercore/reference/objectpath.go
+++ b/code/go/0chain.net/blobbercore/reference/objectpath.go
@@ -2,6 +2,7 @@ package reference
 
 import (
 	"context"
+	"fmt"
 
 	"0chain.net/core/common"
 )
@@ -23,7 +24,7 @@ func GetObjectPath(ctx context.Context, allocationID string, blockNum int64) (*O
 	}
 
 	if rootRef.NumBlocks < blockNum {
-		return nil, common.NewError("invalid_block_num", "Invalid block number"+string(rootRef.NumBlocks)+" / "+string(blockNum))
+		return nil, common.NewError("invalid_block_num", fmt.Sprintf("Invalid block number %d/%d", rootRef.NumBlocks, blockNum))
 	}
 
 	if rootRef.NumBlocks == 0 {
diff --git a/code/go/0chain.net/blobbercore/reference/ref.go b/code/go/0chain.net/blobbercore/reference/ref.go
index 4de475fe0..f422f501f 100644
--- a/code/go/0chain.net/blobbercore/reference/ref.go
+++ b/code/go/0chain.net/blobbercore/reference/ref.go
@@ -56,7 +56,7 @@ func (a *Attributes) Validate() (err error) {
 }
 
 type Ref struct {
-	ID                  int64          `gorm:column:id;primary_key`
+	ID                  int64          `gorm:"column:id;primary_key"`
 	Type                string         `gorm:"column:type" dirlist:"type" filelist:"type"`
 	AllocationID        string         `gorm:"column:allocation_id"`
 	LookupHash          string         `gorm:"column:lookup_hash" dirlist:"lookup_hash" filelist:"lookup_hash"`
diff --git a/code/go/0chain.net/blobbercore/reference/referencepath.go b/code/go/0chain.net/blobbercore/reference/referencepath.go
index 88c154f98..cc424a25e 100644
--- a/code/go/0chain.net/blobbercore/reference/referencepath.go
+++ b/code/go/0chain.net/blobbercore/reference/referencepath.go
@@ -58,27 +58,9 @@ func GetReferencePathFromPaths(ctx context.Context, allocationID string, paths [
 		}
 	}
 
-	// curLevel := 2
-	// subDirs := GetSubDirsFromPath(path)
-	// var foundRef *Ref
-	// for i := 1; i < len(refs); i++ {
-	// 	if refs[i].ParentPath != curRef.Path && foundRef != nil {
-	// 		curLevel++
-	// 		curRef = foundRef
-	// 		foundRef = nil
-	// 	}
-
-	// 	if refs[i].ParentPath == curRef.Path {
-	// 		if len(subDirs) > (curLevel-2) && subDirs[curLevel-2] == refs[i].Name {
-	// 			//curRef = &refs[i]
-	// 			foundRef = &refs[i]
-	// 		}
-	// 		curRef.AddChild(&refs[i])
-	// 	} else {
-	// 		return nil, common.NewError("invalid_dir_tree", "DB has invalid tree.")
-	// 	}
-	// }
-	refs[0].CalculateHash(ctx, false)
+	if _, err := refs[0].CalculateHash(ctx, false); err != nil {
+		return nil, common.NewError("Ref_CalculateHash", err.Error())
+	}
 	return &refs[0], nil
 }
 
diff --git a/code/go/0chain.net/blobbercore/stats/blobberstats.go b/code/go/0chain.net/blobbercore/stats/blobberstats.go
index 1e8fa1d45..9a2db17a9 100644
--- a/code/go/0chain.net/blobbercore/stats/blobberstats.go
+++ b/code/go/0chain.net/blobbercore/stats/blobberstats.go
@@ -274,7 +274,9 @@ func (bs *BlobberStats) loadAllocationStats(ctx context.Context) {
 			return
 		}
 		as.UsedSize = as.FilesSize + as.ThumbnailsSize
-		as.loadAllocationDiskUsageStats()
+		if err := as.loadAllocationDiskUsageStats(); err != nil {
+			Logger.Error("AllocationStats_loadAllocationDiskUsageStats", zap.String("allocation_id", as.AllocationID), zap.Error(err))
+		}
 		bs.AllocationStats = append(bs.AllocationStats, as)
 	}
 
diff --git a/code/go/0chain.net/blobbercore/stats/filestats.go b/code/go/0chain.net/blobbercore/stats/filestats.go
index 4a235d550..8ce642387 100644
--- a/code/go/0chain.net/blobbercore/stats/filestats.go
+++ b/code/go/0chain.net/blobbercore/stats/filestats.go
@@ -9,7 +9,7 @@ import (
 )
 
 type FileStats struct {
-	ID                       int64  `gorm:column:id;primary_key json:"-"`
+	ID                       int64  `gorm:"column:id;primary_key" json:"-"`
 	RefID                    int64  `gorm:"column:ref_id" json:"-"`
 	NumUpdates               int64  `gorm:"column:num_of_updates" json:"num_of_updates"`
 	NumBlockDownloads        int64  `gorm:"column:num_of_block_downloads" json:"num_of_block_downloads"`
diff --git a/code/go/0chain.net/blobbercore/writemarker/protocol.go b/code/go/0chain.net/blobbercore/writemarker/protocol.go
index 38b73b36b..c152adde2 100644
--- a/code/go/0chain.net/blobbercore/writemarker/protocol.go
+++ b/code/go/0chain.net/blobbercore/writemarker/protocol.go
@@ -88,7 +88,9 @@ func (wm *WriteMarkerEntity) RedeemMarker(ctx context.Context) error {
 	if err != nil {
 		wm.StatusMessage = "Error creating transaction entity. " + err.Error()
 		wm.ReedeemRetries++
-		wm.UpdateStatus(ctx, Failed, "Error creating transaction entity. "+err.Error(), "")
+		if err := wm.UpdateStatus(ctx, Failed, "Error creating transaction entity. "+err.Error(), ""); err != nil {
+			Logger.Error("WriteMarkerEntity_UpdateStatus", zap.Error(err))
+		}
 		return err
 	}
 
@@ -103,7 +105,9 @@ func (wm *WriteMarkerEntity) RedeemMarker(ctx context.Context) error {
 		wm.Status = Failed
 		wm.StatusMessage = "Error encoding sc input. " + err.Error()
 		wm.ReedeemRetries++
-		wm.UpdateStatus(ctx, Failed, "Error encoding sc input. "+err.Error(), "")
+		if err := wm.UpdateStatus(ctx, Failed, "Error encoding sc input. "+err.Error(), ""); err != nil {
+			Logger.Error("WriteMarkerEntity_UpdateStatus", zap.Error(err))
+		}
 		return err
 	}
 
@@ -113,7 +117,9 @@ func (wm *WriteMarkerEntity) RedeemMarker(ctx context.Context) error {
 		wm.Status = Failed
 		wm.StatusMessage = "Failed during sending close connection to the miner. " + err.Error()
 		wm.ReedeemRetries++
-		wm.UpdateStatus(ctx, Failed, "Failed during sending close connection to the miner. "+err.Error(), "")
+		if err := wm.UpdateStatus(ctx, Failed, "Failed during sending close connection to the miner. "+err.Error(), ""); err != nil {
+			Logger.Error("WriteMarkerEntity_UpdateStatus", zap.Error(err))
+		}
 		return err
 	}
 
@@ -125,7 +131,9 @@ func (wm *WriteMarkerEntity) RedeemMarker(ctx context.Context) error {
 		wm.StatusMessage = "Error verifying the close connection transaction." + err.Error()
 		wm.ReedeemRetries++
 		wm.CloseTxnID = txn.Hash
-		wm.UpdateStatus(ctx, Failed, "Error verifying the close connection transaction."+err.Error(), txn.Hash)
+		if err := wm.UpdateStatus(ctx, Failed, "Error verifying the close connection transaction."+err.Error(), txn.Hash); err != nil {
+			Logger.Error("WriteMarkerEntity_UpdateStatus", zap.Error(err))
+		}
 		return err
 	}
 	wm.Status = Committed
diff --git a/code/go/0chain.net/blobbercore/writemarker/worker.go b/code/go/0chain.net/blobbercore/writemarker/worker.go
index 47dde77c5..7456d5d49 100644
--- a/code/go/0chain.net/blobbercore/writemarker/worker.go
+++ b/code/go/0chain.net/blobbercore/writemarker/worker.go
@@ -70,7 +70,7 @@ func RedeemWriteMarkers(ctx context.Context) {
 	var ticker = time.NewTicker(
 		time.Duration(config.Configuration.WMRedeemFreq) * time.Second,
 	)
-	for true {
+	for {
 		select {
 		case <-ctx.Done():
 			return
diff --git a/code/go/0chain.net/conductor/conductrpc/client.go b/code/go/0chain.net/conductor/conductrpc/client.go
index bf21e9429..97db9917a 100644
--- a/code/go/0chain.net/conductor/conductrpc/client.go
+++ b/code/go/0chain.net/conductor/conductrpc/client.go
@@ -24,7 +24,7 @@ func newClient(address string) (c *client, err error) {
 	return
 }
 
-func (c *client) dial() (err error) {
+func (c *client) dial() (err error) { //nolint:unused,deadcode // might be used later?
 	c.client, err = rpc.Dial("tcp", c.address)
 	return
 }
diff --git a/code/go/0chain.net/conductor/conductrpc/entity.go b/code/go/0chain.net/conductor/conductrpc/entity.go
index 8001fd919..fd983d2e4 100644
--- a/code/go/0chain.net/conductor/conductrpc/entity.go
+++ b/code/go/0chain.net/conductor/conductrpc/entity.go
@@ -95,7 +95,7 @@ func (e *Entity) Shutdown() {
 	})
 }
 
-func (e *Entity) isMonitor() bool {
+func (e *Entity) isMonitor() bool { //nolint:unused,deadcode // might be used later?
 	var state = e.State()
 	return state != nil && state.IsMonitor
 }
diff --git a/code/go/0chain.net/conductor/conductrpc/state.go b/code/go/0chain.net/conductor/conductrpc/state.go
index e29c47029..c3ab62d8a 100644
--- a/code/go/0chain.net/conductor/conductrpc/state.go
+++ b/code/go/0chain.net/conductor/conductrpc/state.go
@@ -56,14 +56,14 @@ func (s *State) Name(id NodeID) NodeName {
 	return s.Nodes[id] // id -> name (or empty string)
 }
 
-func (s *State) copy() (cp *State) {
+func (s *State) copy() (cp *State) { //nolint:unused,deadcode // might be used later?
 	cp = new(State)
 	(*cp) = (*s)
 	return
 
 }
 
-func (s *State) send(poll chan *State) {
+func (s *State) send(poll chan *State) { //nolint:unused,deadcode // might be used later?
 	go func(state *State) {
 		poll <- state
 	}(s.copy())
diff --git a/code/go/0chain.net/core/cache/lru.go b/code/go/0chain.net/core/cache/lru.go
index 5dc012cc7..31c650b3a 100644
--- a/code/go/0chain.net/core/cache/lru.go
+++ b/code/go/0chain.net/core/cache/lru.go
@@ -18,8 +18,7 @@ func NewLRUCache(size int) *LRU {
 
 //Add - add a key and a value
 func (c *LRU) Add(key string, value interface{}) error {
-	c.Cache.Set(key, value)
-	return nil
+	return c.Cache.Set(key, value)
 }
 
 //Get - get the value associated with the key
diff --git a/code/go/0chain.net/core/common/context.go b/code/go/0chain.net/core/common/context.go
index c7ce76bbe..63eebfb32 100644
--- a/code/go/0chain.net/core/common/context.go
+++ b/code/go/0chain.net/core/common/context.go
@@ -7,6 +7,10 @@ import (
 	"os/signal"
 	"syscall"
 	"time"
+
+	"0chain.net/core/logging"
+
+	"go.uber.org/zap"
 )
 
 var ErrStop = NewError("stop_error", "Stop signal error")
@@ -20,7 +24,7 @@ func SetupRootContext(nodectx context.Context) {
 	// TODO: This go routine is not needed. Workaround for the "vet" error
 	done := make(chan bool)
 	go func() {
-		select {
+		select { //nolint:gosimple // need more time to verify
 		case <-done:
 			//Logger.Info("Shutting down all workers...")
 			rootCancel()
@@ -53,12 +57,16 @@ func HandleShutdown(server *http.Server) {
 			case syscall.SIGINT:
 				Done()
 				ctx, cancelf := context.WithTimeout(context.Background(), 5*time.Second)
-				server.Shutdown(ctx)
+				if err := server.Shutdown(ctx); err != nil {
+					logging.Logger.Error("server failed to gracefully shuts down", zap.Error(err))
+				}
 				cancelf()
 			case syscall.SIGQUIT:
 				Done()
 				ctx, cancelf := context.WithTimeout(context.Background(), 5*time.Second)
-				server.Shutdown(ctx)
+				if err := server.Shutdown(ctx); err != nil {
+					logging.Logger.Error("server failed to gracefully shuts down", zap.Error(err))
+				}
 				cancelf()
 			default:
 				//Logger.Debug("unhandled signal", zap.Any("signal", sig))
diff --git a/code/go/0chain.net/core/common/handler.go b/code/go/0chain.net/core/common/handler.go
index 486bc845e..b7ca37938 100644
--- a/code/go/0chain.net/core/common/handler.go
+++ b/code/go/0chain.net/core/common/handler.go
@@ -42,21 +42,21 @@ func Respond(w http.ResponseWriter, data interface{}, err error) {
 			data["code"] = cerr.Code
 		}
 		buf := bytes.NewBuffer(nil)
-		json.NewEncoder(buf).Encode(data)
+		json.NewEncoder(buf).Encode(data) //nolint:errcheck // checked in previous step
 		http.Error(w, buf.String(), 400)
 	} else {
 		if data != nil {
-			json.NewEncoder(w).Encode(data)
+			json.NewEncoder(w).Encode(data) //nolint:errcheck // checked in previous step
 		}
 	}
 }
 
-func getContext(r *http.Request) (context.Context, error) {
+func getContext(r *http.Request) (context.Context, error) { //nolint:unused,deadcode // might be used later?
 	ctx := r.Context()
 	return ctx, nil
 }
 
-var domainRE = regexp.MustCompile(`^(?:https?:\/\/)?(?:[^@\/\n]+@)?(?:www\.)?([^:\/\n]+)`)
+var domainRE = regexp.MustCompile(`^(?:https?:\/\/)?(?:[^@\/\n]+@)?(?:www\.)?([^:\/\n]+)`) //nolint:unused,deadcode,varcheck // might be used later?
 
 func ToByteStream(handler JSONResponderF) ReqRespHandlerf {
 	return func(w http.ResponseWriter, r *http.Request) {
@@ -75,14 +75,13 @@ func ToByteStream(handler JSONResponderF) ReqRespHandlerf {
 
 		} else {
 			if data != nil {
-				//json.NewEncoder(w).Encode(data)
 				rawdata, ok := data.([]byte)
 				if ok {
 					w.Header().Set("Content-Type", "application/octet-stream")
-					w.Write(rawdata)
+					w.Write(rawdata) //nolint:errcheck
 				} else {
 					w.Header().Set("Content-Type", "application/json")
-					json.NewEncoder(w).Encode(data)
+					json.NewEncoder(w).Encode(data) //nolint:errcheck
 				}
 			}
 		}
diff --git a/code/go/0chain.net/core/common/time.go b/code/go/0chain.net/core/common/time.go
index 5b14bc52e..d5ede55ba 100644
--- a/code/go/0chain.net/core/common/time.go
+++ b/code/go/0chain.net/core/common/time.go
@@ -1,7 +1,6 @@
 package common
 
 import (
-	"math/rand"
 	"time"
 )
 
@@ -18,5 +17,3 @@ func Within(ts int64, seconds int64) bool {
 	now := time.Now().Unix()
 	return now > ts-seconds && now < ts+seconds
 }
-
-var randGenerator = rand.New(rand.NewSource(time.Now().UnixNano()))
diff --git a/code/go/0chain.net/core/lock/lock.go b/code/go/0chain.net/core/lock/lock.go
index 843e94cae..933b85e30 100644
--- a/code/go/0chain.net/core/lock/lock.go
+++ b/code/go/0chain.net/core/lock/lock.go
@@ -2,7 +2,7 @@ package lock
 
 import "sync"
 
-var lockPool = make(map[string]*sync.Mutex, 0)
+var lockPool = make(map[string]*sync.Mutex, 0) //nolint:gosimple // need more time to verify: declaring capacity is probably necessary?
 var lockMutex = &sync.Mutex{}
 
 func GetMutex(tablename string, key string) *sync.Mutex {
diff --git a/code/go/0chain.net/core/logging/logger.go b/code/go/0chain.net/core/logging/logger.go
index 6db3cc055..31bf5ccb3 100644
--- a/code/go/0chain.net/core/logging/logger.go
+++ b/code/go/0chain.net/core/logging/logger.go
@@ -33,7 +33,7 @@ func InitLogging(mode string, logDir string, logFile string) {
 		logWriter = zapcore.NewMultiWriteSyncer(zapcore.AddSync(os.Stdout), logWriter)
 
 	}
-	cfg.Level.UnmarshalText([]byte(viper.GetString("logging.level")))
+	_ = cfg.Level.UnmarshalText([]byte(viper.GetString("logging.level")))
 	cfg.Encoding = "console"
 	cfg.EncoderConfig.TimeKey = "timestamp"
 	cfg.EncoderConfig.EncodeTime = zapcore.ISO8601TimeEncoder
@@ -72,6 +72,6 @@ func getWriteSyncer(logName string) zapcore.WriteSyncer {
 		LocalTime:  true,
 		Compress:   false, // disabled by default
 	}
-	ioWriter.Rotate()
+	_ = ioWriter.Rotate()
 	return zapcore.AddSync(ioWriter)
 }
diff --git a/code/go/0chain.net/core/transaction/entity.go b/code/go/0chain.net/core/transaction/entity.go
index 2d61ca771..72f8eabe5 100644
--- a/code/go/0chain.net/core/transaction/entity.go
+++ b/code/go/0chain.net/core/transaction/entity.go
@@ -153,7 +153,9 @@ func (t *Transaction) ExecuteSmartContract(address, methodName, input string, va
 }
 
 func (t *Transaction) Verify() error {
-	t.zcntxn.SetTransactionHash(t.Hash)
+	if err := t.zcntxn.SetTransactionHash(t.Hash); err != nil {
+		return err
+	}
 	t.wg.Add(1)
 	err := t.zcntxn.Verify()
 	if err != nil {
diff --git a/code/go/0chain.net/core/util/http.go b/code/go/0chain.net/core/util/http.go
index eac2641b9..920af26d7 100644
--- a/code/go/0chain.net/core/util/http.go
+++ b/code/go/0chain.net/core/util/http.go
@@ -36,7 +36,7 @@ func SendMultiPostRequest(urls []string, data []byte) {
 	wg.Add(len(urls))
 
 	for _, url := range urls {
-		go SendPostRequest(url, data, &wg)
+		go SendPostRequest(url, data, &wg) //nolint:errcheck // goroutines
 	}
 	wg.Wait()
 }
diff --git a/code/go/0chain.net/core/util/merkle_tree.go b/code/go/0chain.net/core/util/merkle_tree.go
index f665bda2c..675b05df2 100644
--- a/code/go/0chain.net/core/util/merkle_tree.go
+++ b/code/go/0chain.net/core/util/merkle_tree.go
@@ -116,7 +116,7 @@ func (mt *MerkleTree) VerifyPath(hash Hashable, path *MTPath) bool {
 
 /*GetPathByIndex - get the path of a leaf node at index i */
 func (mt *MerkleTree) GetPathByIndex(idx int) *MTPath {
-	path := make([]string, mt.levels-1, mt.levels-1)
+	path := make([]string, mt.levels-1, mt.levels-1) //nolint:gosimple // need more time to verify: declaring capacity is probably necessary?
 	mpath := &MTPath{LeafIndex: idx}
 	if idx&1 == 1 {
 		path[0] = mt.tree[idx-1]
diff --git a/code/go/0chain.net/core/util/merkle_tree_test.go b/code/go/0chain.net/core/util/merkle_tree_test.go
index 2f39d98c5..da84b49af 100644
--- a/code/go/0chain.net/core/util/merkle_tree_test.go
+++ b/code/go/0chain.net/core/util/merkle_tree_test.go
@@ -65,7 +65,10 @@ func TestMerkleTreeSetTree(t *testing.T) {
 	var mt MerkleTreeI = &MerkleTree{}
 	mt.ComputeTree(txns)
 	var mt2 MerkleTreeI = &MerkleTree{}
-	mt2.SetTree(len(txns), mt.GetTree())
+	err := mt2.SetTree(len(txns), mt.GetTree())
+	if err != nil {
+		t.Error(err)
+	}
 	if mt.GetRoot() != mt2.GetRoot() {
 		t.Errorf("Merkle roots didn't match")
 	}
diff --git a/code/go/0chain.net/validator/main.go b/code/go/0chain.net/validator/main.go
index e68049e4b..684041f31 100644
--- a/code/go/0chain.net/validator/main.go
+++ b/code/go/0chain.net/validator/main.go
@@ -115,7 +115,9 @@ func main() {
 
 	chain.SetServerChain(serverChain)
 
-	SetupValidatorOnBC(*logDir)
+	if err := SetupValidatorOnBC(*logDir); err != nil {
+		Logger.Info("error setting up validator on blockchain", zap.Any("err", err))
+	}
 
 	mode := "main net"
 	if config.Development() {
@@ -171,7 +173,6 @@ func RegisterValidator() {
 			time.Sleep(transaction.SLEEP_FOR_TXN_CONFIRMATION * time.Second)
 			t, err := transaction.VerifyTransaction(txnHash, chain.GetServerChain())
 			if err == nil {
-				txnVerified = true
 				Logger.Info("Transaction for adding validator accepted and verified", zap.String("txn_hash", t.Hash), zap.Any("txn_output", t.TransactionOutput))
 				return
 			}
@@ -184,13 +185,18 @@ func RegisterValidator() {
 	}
 }
 
-func SetupValidatorOnBC(logDir string) {
+func SetupValidatorOnBC(logDir string) error {
 	var logName = logDir + "/validator.log"
 	zcncore.SetLogFile(logName, false)
 	zcncore.SetLogLevel(3)
-	zcncore.InitZCNSDK(serverChain.BlockWorker, config.Configuration.SignatureScheme)
-	zcncore.SetWalletInfo(node.Self.GetWalletString(), false)
+	if err := zcncore.InitZCNSDK(serverChain.BlockWorker, config.Configuration.SignatureScheme); err != nil {
+		return err
+	}
+	if err := zcncore.SetWalletInfo(node.Self.GetWalletString(), false); err != nil {
+		return err
+	}
 	go RegisterValidator()
+	return nil
 }
 
 /*HomePageHandler - provides basic info when accessing the home page of the server */
diff --git a/code/go/0chain.net/validatorcore/storage/challenge_handler.go b/code/go/0chain.net/validatorcore/storage/challenge_handler.go
index d8a321b97..528eb6531 100644
--- a/code/go/0chain.net/validatorcore/storage/challenge_handler.go
+++ b/code/go/0chain.net/validatorcore/storage/challenge_handler.go
@@ -87,7 +87,9 @@ func ChallengeHandler(ctx context.Context, r *http.Request) (interface{}, error)
 		validationTicket.ValidatorID = node.Self.ID
 		validationTicket.ValidatorKey = node.Self.PublicKey
 		validationTicket.Timestamp = common.Now()
-		validationTicket.Sign()
+		if err := validationTicket.Sign(); err != nil {
+			return nil, common.NewError("invalid_parameters", err.Error())
+		}
 		return &validationTicket, nil
 	}
 
@@ -99,10 +101,12 @@ func ChallengeHandler(ctx context.Context, r *http.Request) (interface{}, error)
 	validationTicket.ValidatorID = node.Self.ID
 	validationTicket.ValidatorKey = node.Self.PublicKey
 	validationTicket.Timestamp = common.Now()
-	validationTicket.Sign()
+	if err := validationTicket.Sign(); err != nil {
+		return nil, common.NewError("invalid_parameters", err.Error())
+	}
 	Logger.Info("Validation passed.", zap.Any("challenge_id", challengeRequest.ChallengeID))
 
-	lru.Add(challengeHash, &validationTicket)
+	lru.Add(challengeHash, &validationTicket) //nolint:errcheck // never returns an error anyway
 	return &validationTicket, nil
 
 }
diff --git a/code/go/0chain.net/validatorcore/storage/handler.go b/code/go/0chain.net/validatorcore/storage/handler.go
index 79e08f091..6f6e01713 100644
--- a/code/go/0chain.net/validatorcore/storage/handler.go
+++ b/code/go/0chain.net/validatorcore/storage/handler.go
@@ -18,6 +18,6 @@ func SetupHandlers(r *mux.Router) {
 }
 
 func DumpGoRoutines(ctx context.Context, r *http.Request) (interface{}, error) {
-	pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
+	_ = pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
 	return "success", nil
 }
diff --git a/code/go/0chain.net/validatorcore/storage/writemarker/entity_test.go b/code/go/0chain.net/validatorcore/storage/writemarker/entity_test.go
index 1212947d6..5747886e8 100644
--- a/code/go/0chain.net/validatorcore/storage/writemarker/entity_test.go
+++ b/code/go/0chain.net/validatorcore/storage/writemarker/entity_test.go
@@ -127,7 +127,10 @@ func setupEntityTest(t *testing.T) (*writemarker.WriteMarker, *zcncrypto.Wallet,
 	}
 	wm.ClientID = wallet.ClientID
 
-	sigSch.SetPrivateKey(wallet.Keys[0].PrivateKey)
+	err = sigSch.SetPrivateKey(wallet.Keys[0].PrivateKey)
+	if err != nil {
+		return wm, wallet, err
+	}
 	sig, err := sigSch.Sign(encryption.Hash(wm.GetHashData()))
 	if err != nil {
 		return wm, wallet, err