diff --git a/accounts/abi/unpack.go b/accounts/abi/unpack.go
index ffa14ccd3b..57732797b6 100644
--- a/accounts/abi/unpack.go
+++ b/accounts/abi/unpack.go
@@ -38,7 +38,7 @@ type unpacker interface {
 func readInteger(kind reflect.Kind, b []byte) interface{} {
 	switch kind {
 	case reflect.Uint8:
-		return uint8(b[len(b)-1])
+		return b[len(b)-1]
 	case reflect.Uint16:
 		return binary.BigEndian.Uint16(b[len(b)-2:])
 	case reflect.Uint32:
diff --git a/build/ci.go b/build/ci.go
index af58ee6452..0c825ef31e 100644
--- a/build/ci.go
+++ b/build/ci.go
@@ -322,9 +322,15 @@ func doLint(cmdline []string) {
 	build.MustRun(goTool("get", "gopkg.in/alecthomas/gometalinter.v1"))
 	build.MustRunCommand(filepath.Join(GOBIN, "gometalinter.v1"), "--install")
 
+	// Run fast linters batched together
 	configs := []string{"--vendor", "--disable-all", "--enable=vet", "--enable=gofmt", "--enable=misspell"}
-
 	build.MustRunCommand(filepath.Join(GOBIN, "gometalinter.v1"), append(configs, packages...)...)
+
+	// Run slow linters one by one
+	for _, linter := range []string{"unconvert"} {
+		configs = []string{"--vendor", "--deadline=10m", "--disable-all", "--enable=" + linter}
+		build.MustRunCommand(filepath.Join(GOBIN, "gometalinter.v1"), append(configs, packages...)...)
+	}
 }
 
 // Release Packaging
diff --git a/cmd/puppeth/module_faucet.go b/cmd/puppeth/module_faucet.go
index acf1e4324e..3c1296bddb 100644
--- a/cmd/puppeth/module_faucet.go
+++ b/cmd/puppeth/module_faucet.go
@@ -133,7 +133,7 @@ func deployFaucet(client *sshClient, network string, bootnodes []string, config
 	})
 	files[filepath.Join(workdir, "docker-compose.yaml")] = composefile.Bytes()
 
-	files[filepath.Join(workdir, "genesis.json")] = []byte(config.node.genesis)
+	files[filepath.Join(workdir, "genesis.json")] = config.node.genesis
 	files[filepath.Join(workdir, "account.json")] = []byte(config.node.keyJSON)
 	files[filepath.Join(workdir, "account.pass")] = []byte(config.node.keyPass)
 
diff --git a/cmd/puppeth/module_node.go b/cmd/puppeth/module_node.go
index 8f912f9ebd..375e3e6463 100644
--- a/cmd/puppeth/module_node.go
+++ b/cmd/puppeth/module_node.go
@@ -128,7 +128,7 @@ func deployNode(client *sshClient, network string, bootv4, bootv5 []string, conf
 	files[filepath.Join(workdir, "docker-compose.yaml")] = composefile.Bytes()
 
 	//genesisfile, _ := json.MarshalIndent(config.genesis, "", "  ")
-	files[filepath.Join(workdir, "genesis.json")] = []byte(config.genesis)
+	files[filepath.Join(workdir, "genesis.json")] = config.genesis
 
 	if config.keyJSON != "" {
 		files[filepath.Join(workdir, "signer.json")] = []byte(config.keyJSON)
diff --git a/cmd/puppeth/ssh.go b/cmd/puppeth/ssh.go
index 26f8466850..47378a6063 100644
--- a/cmd/puppeth/ssh.go
+++ b/cmd/puppeth/ssh.go
@@ -27,7 +27,6 @@ import (
 	"os/user"
 	"path/filepath"
 	"strings"
-	"syscall"
 
 	"github.com/ethereum/go-ethereum/log"
 	"golang.org/x/crypto/ssh"
@@ -85,7 +84,7 @@ func dial(server string, pubkey []byte) (*sshClient, error) {
 	}
 	auths = append(auths, ssh.PasswordCallback(func() (string, error) {
 		fmt.Printf("What's the login password for %s at %s? (won't be echoed)\n> ", login, server)
-		blob, err := terminal.ReadPassword(int(syscall.Stdin))
+		blob, err := terminal.ReadPassword(int(os.Stdin.Fd()))
 
 		fmt.Println()
 		return string(blob), err
diff --git a/cmd/puppeth/wizard.go b/cmd/puppeth/wizard.go
index 5fbc11cb98..eb6d9e5aae 100644
--- a/cmd/puppeth/wizard.go
+++ b/cmd/puppeth/wizard.go
@@ -28,7 +28,6 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-	"syscall"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -231,7 +230,7 @@ func (w *wizard) readDefaultFloat(def float64) float64 {
 // line and returns it. The input will not be echoed.
 func (w *wizard) readPassword() string {
 	fmt.Printf("> ")
-	text, err := terminal.ReadPassword(int(syscall.Stdin))
+	text, err := terminal.ReadPassword(int(os.Stdin.Fd()))
 	if err != nil {
 		log.Crit("Failed to read password", "err", err)
 	}
diff --git a/common/hexutil/hexutil.go b/common/hexutil/hexutil.go
index 582a67c22c..02c488a3f1 100644
--- a/common/hexutil/hexutil.go
+++ b/common/hexutil/hexutil.go
@@ -53,9 +53,7 @@ var (
 
 type decError struct{ msg string }
 
-func (err decError) Error() string {
-	return string(err.msg)
-}
+func (err decError) Error() string { return err.msg }
 
 // Decode decodes a hex string with 0x prefix.
 func Decode(input string) ([]byte, error) {
diff --git a/common/hexutil/json.go b/common/hexutil/json.go
index 11e14cae7f..fbc21241c8 100644
--- a/common/hexutil/json.go
+++ b/common/hexutil/json.go
@@ -223,7 +223,7 @@ func (b *Uint64) UnmarshalText(input []byte) error {
 			return ErrSyntax
 		}
 		dec *= 16
-		dec += uint64(nib)
+		dec += nib
 	}
 	*b = Uint64(dec)
 	return nil
diff --git a/consensus/ethash/algorithm_go1.8.go b/consensus/ethash/algorithm_go1.8.go
index 62bf4dec1b..d691b758f0 100644
--- a/consensus/ethash/algorithm_go1.8.go
+++ b/consensus/ethash/algorithm_go1.8.go
@@ -31,7 +31,7 @@ func cacheSize(block uint64) uint64 {
 		return cacheSizes[epoch]
 	}
 	// No known cache size, calculate manually (sanity branch only)
-	size := uint64(cacheInitBytes + cacheGrowthBytes*uint64(epoch) - hashBytes)
+	size := cacheInitBytes + cacheGrowthBytes*uint64(epoch) - hashBytes
 	for !new(big.Int).SetUint64(size / hashBytes).ProbablyPrime(1) { // Always accurate for n < 2^64
 		size -= 2 * hashBytes
 	}
@@ -49,7 +49,7 @@ func datasetSize(block uint64) uint64 {
 		return datasetSizes[epoch]
 	}
 	// No known dataset size, calculate manually (sanity branch only)
-	size := uint64(datasetInitBytes + datasetGrowthBytes*uint64(epoch) - mixBytes)
+	size := datasetInitBytes + datasetGrowthBytes*uint64(epoch) - mixBytes
 	for !new(big.Int).SetUint64(size / mixBytes).ProbablyPrime(1) { // Always accurate for n < 2^64
 		size -= 2 * mixBytes
 	}
diff --git a/core/vm/interpreter.go b/core/vm/interpreter.go
index 516438509f..ea5468f901 100644
--- a/core/vm/interpreter.go
+++ b/core/vm/interpreter.go
@@ -161,8 +161,8 @@ func (in *Interpreter) Run(snapshot int, contract *Contract, input []byte) (ret
 
 		if in.cfg.Debug {
 			logged = false
-			pcCopy = uint64(pc)
-			gasCopy = uint64(contract.Gas)
+			pcCopy = pc
+			gasCopy = contract.Gas
 			stackCopy = newstack()
 			for _, val := range stack.data {
 				stackCopy.push(val)
diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index 5782d4cf53..cca4fe7a93 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -708,7 +708,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
 		ttl := d.requestTTL()
 		timeout := time.After(ttl)
 
-		go p.peer.RequestHeadersByNumber(uint64(check), 1, 0, false)
+		go p.peer.RequestHeadersByNumber(check, 1, 0, false)
 
 		// Wait until a reply arrives to this request
 		for arrived := false; !arrived; {
@@ -1518,7 +1518,7 @@ func (d *Downloader) deliver(id string, destCh chan dataPack, packet dataPack, i
 func (d *Downloader) qosTuner() {
 	for {
 		// Retrieve the current median RTT and integrate into the previoust target RTT
-		rtt := time.Duration(float64(1-qosTuningImpact)*float64(atomic.LoadUint64(&d.rttEstimate)) + qosTuningImpact*float64(d.peers.medianRTT()))
+		rtt := time.Duration((1-qosTuningImpact)*float64(atomic.LoadUint64(&d.rttEstimate)) + qosTuningImpact*float64(d.peers.medianRTT()))
 		atomic.StoreUint64(&d.rttEstimate, uint64(rtt))
 
 		// A new RTT cycle passed, increase our confidence in the estimated RTT
diff --git a/eth/downloader/fakepeer.go b/eth/downloader/fakepeer.go
index ebdb9c3342..b45acff7d0 100644
--- a/eth/downloader/fakepeer.go
+++ b/eth/downloader/fakepeer.go
@@ -62,7 +62,7 @@ func (p *FakePeer) RequestHeadersByHash(hash common.Hash, amount int, skip int,
 		number := origin.Number.Uint64()
 		headers = append(headers, origin)
 		if reverse {
-			for i := 0; i < int(skip)+1; i++ {
+			for i := 0; i <= skip; i++ {
 				if header := p.hc.GetHeader(hash, number); header != nil {
 					hash = header.ParentHash
 					number--
diff --git a/eth/filters/filter.go b/eth/filters/filter.go
index d16af84ee8..e208f8f38e 100644
--- a/eth/filters/filter.go
+++ b/eth/filters/filter.go
@@ -206,7 +206,7 @@ func (f *Filter) checkMatches(ctx context.Context, header *types.Header) (logs [
 	}
 	var unfiltered []*types.Log
 	for _, receipt := range receipts {
-		unfiltered = append(unfiltered, ([]*types.Log)(receipt.Logs)...)
+		unfiltered = append(unfiltered, receipt.Logs...)
 	}
 	logs = filterLogs(unfiltered, nil, nil, f.addresses, f.topics)
 	if len(logs) > 0 {
diff --git a/les/peer.go b/les/peer.go
index 524690e2f5..04d747a6b3 100644
--- a/les/peer.go
+++ b/les/peer.go
@@ -400,7 +400,7 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 
 	var send keyValueList
 	send = send.add("protocolVersion", uint64(p.version))
-	send = send.add("networkId", uint64(p.network))
+	send = send.add("networkId", p.network)
 	send = send.add("headTd", td)
 	send = send.add("headHash", head)
 	send = send.add("headNum", headNum)
diff --git a/metrics/metrics.go b/metrics/metrics.go
index da2cdbc53c..afdfd89fa7 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -112,10 +112,10 @@ func CollectProcessMetrics(refresh time.Duration) {
 		memPauses.Mark(int64(memstats[i%2].PauseTotalNs - memstats[(i-1)%2].PauseTotalNs))
 
 		if ReadDiskStats(diskstats[i%2]) == nil {
-			diskReads.Mark(int64(diskstats[i%2].ReadCount - diskstats[(i-1)%2].ReadCount))
-			diskReadBytes.Mark(int64(diskstats[i%2].ReadBytes - diskstats[(i-1)%2].ReadBytes))
-			diskWrites.Mark(int64(diskstats[i%2].WriteCount - diskstats[(i-1)%2].WriteCount))
-			diskWriteBytes.Mark(int64(diskstats[i%2].WriteBytes - diskstats[(i-1)%2].WriteBytes))
+			diskReads.Mark(diskstats[i%2].ReadCount - diskstats[(i-1)%2].ReadCount)
+			diskReadBytes.Mark(diskstats[i%2].ReadBytes - diskstats[(i-1)%2].ReadBytes)
+			diskWrites.Mark(diskstats[i%2].WriteCount - diskstats[(i-1)%2].WriteCount)
+			diskWriteBytes.Mark(diskstats[i%2].WriteBytes - diskstats[(i-1)%2].WriteBytes)
 		}
 		time.Sleep(refresh)
 	}
diff --git a/mobile/interface.go b/mobile/interface.go
index 72958e66a2..ac0c26088a 100644
--- a/mobile/interface.go
+++ b/mobile/interface.go
@@ -59,7 +59,7 @@ func (i *Interface) SetInt64(n int64)              { i.object = &n }
 func (i *Interface) SetUint8(bigint *BigInt)       { n := uint8(bigint.bigint.Uint64()); i.object = &n }
 func (i *Interface) SetUint16(bigint *BigInt)      { n := uint16(bigint.bigint.Uint64()); i.object = &n }
 func (i *Interface) SetUint32(bigint *BigInt)      { n := uint32(bigint.bigint.Uint64()); i.object = &n }
-func (i *Interface) SetUint64(bigint *BigInt)      { n := uint64(bigint.bigint.Uint64()); i.object = &n }
+func (i *Interface) SetUint64(bigint *BigInt)      { n := bigint.bigint.Uint64(); i.object = &n }
 func (i *Interface) SetBigInt(bigint *BigInt)      { i.object = &bigint.bigint }
 func (i *Interface) SetBigInts(bigints *BigInts)   { i.object = &bigints.bigints }
 
diff --git a/p2p/discover/table.go b/p2p/discover/table.go
index 2f5a26c34c..ec4eb94ad5 100644
--- a/p2p/discover/table.go
+++ b/p2p/discover/table.go
@@ -427,7 +427,7 @@ func (tab *Table) bondall(nodes []*Node) (result []*Node) {
 	rc := make(chan *Node, len(nodes))
 	for i := range nodes {
 		go func(n *Node) {
-			nn, _ := tab.bond(false, n.ID, n.addr(), uint16(n.TCP))
+			nn, _ := tab.bond(false, n.ID, n.addr(), n.TCP)
 			rc <- nn
 		}(nodes[i])
 	}
diff --git a/swarm/api/manifest.go b/swarm/api/manifest.go
index d3eced1980..32b5f80a7c 100644
--- a/swarm/api/manifest.go
+++ b/swarm/api/manifest.go
@@ -238,7 +238,7 @@ func (self *manifestTrie) addEntry(entry *manifestTrieEntry, quitC chan bool) {
 		return
 	}
 
-	b := byte(entry.Path[0])
+	b := entry.Path[0]
 	oldentry := self.entries[b]
 	if (oldentry == nil) || (oldentry.Path == entry.Path && oldentry.ContentType != ManifestType) {
 		self.entries[b] = entry
@@ -294,7 +294,7 @@ func (self *manifestTrie) deleteEntry(path string, quitC chan bool) {
 		return
 	}
 
-	b := byte(path[0])
+	b := path[0]
 	entry := self.entries[b]
 	if entry == nil {
 		return
@@ -425,7 +425,7 @@ func (self *manifestTrie) findPrefixOf(path string, quitC chan bool) (entry *man
 	}
 
 	//see if first char is in manifest entries
-	b := byte(path[0])
+	b := path[0]
 	entry = self.entries[b]
 	if entry == nil {
 		return self.entries[256], 0
diff --git a/swarm/fuse/fuse_file.go b/swarm/fuse/fuse_file.go
index 32c85d02f7..c94a0773f5 100644
--- a/swarm/fuse/fuse_file.go
+++ b/swarm/fuse/fuse_file.go
@@ -19,15 +19,16 @@
 package fuse
 
 import (
+	"errors"
+	"io"
+	"os"
+	"sync"
+
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
-	"errors"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/swarm/storage"
 	"golang.org/x/net/context"
-	"io"
-	"os"
-	"sync"
 )
 
 const (
@@ -87,7 +88,7 @@ func (file *SwarmFile) Attr(ctx context.Context, a *fuse.Attr) error {
 		if err != nil {
 			log.Warn("Couldnt get size of file %s : %v", file.path, err)
 		}
-		file.fileSize = int64(size)
+		file.fileSize = size
 	}
 	a.Size = uint64(file.fileSize)
 	return nil
diff --git a/swarm/network/depo.go b/swarm/network/depo.go
index 8695bf5d98..17540d2f9f 100644
--- a/swarm/network/depo.go
+++ b/swarm/network/depo.go
@@ -55,7 +55,7 @@ func (self *Depo) HandleUnsyncedKeysMsg(req *unsyncedKeysMsgData, p *peer) error
 	var err error
 	for _, req := range unsynced {
 		// skip keys that are found,
-		chunk, err = self.localStore.Get(storage.Key(req.Key[:]))
+		chunk, err = self.localStore.Get(req.Key[:])
 		if err != nil || chunk.SData == nil {
 			missing = append(missing, req)
 		}
diff --git a/swarm/network/kademlia/address.go b/swarm/network/kademlia/address.go
index 16c5ce5322..4c38a846f9 100644
--- a/swarm/network/kademlia/address.go
+++ b/swarm/network/kademlia/address.go
@@ -67,7 +67,7 @@ func proximity(one, other Address) (ret int) {
 	for i := 0; i < len(one); i++ {
 		oxo := one[i] ^ other[i]
 		for j := 0; j < 8; j++ {
-			if (uint8(oxo)>>uint8(7-j))&0x01 != 0 {
+			if (oxo>>uint8(7-j))&0x01 != 0 {
 				return i*8 + j
 			}
 		}
diff --git a/swarm/network/kademlia/kaddb.go b/swarm/network/kademlia/kaddb.go
index 3e4b261fde..cb0869467e 100644
--- a/swarm/network/kademlia/kaddb.go
+++ b/swarm/network/kademlia/kaddb.go
@@ -211,12 +211,12 @@ func (self *KadDb) findBest(maxBinSize int, binSize func(int) int) (node *NodeRe
 				}
 
 				// if node is scheduled to connect
-				if time.Time(node.After).After(time.Now()) {
+				if node.After.After(time.Now()) {
 					log.Debug(fmt.Sprintf("kaddb record %v (PO%03d:%d) skipped. seen at %v (%v ago), scheduled at %v", node.Addr, po, cursor, node.Seen, delta, node.After))
 					continue ROW
 				}
 
-				delta = time.Since(time.Time(node.Seen))
+				delta = time.Since(node.Seen)
 				if delta < self.initialRetryInterval {
 					delta = self.initialRetryInterval
 				}
@@ -230,7 +230,7 @@ func (self *KadDb) findBest(maxBinSize int, binSize func(int) int) (node *NodeRe
 				log.Debug(fmt.Sprintf("kaddb record %v (PO%03d:%d) ready to be tried. seen at %v (%v ago), scheduled at %v", node.Addr, po, cursor, node.Seen, delta, node.After))
 
 				// scheduling next check
-				interval = time.Duration(delta * time.Duration(self.connRetryExp))
+				interval = delta * time.Duration(self.connRetryExp)
 				after = time.Now().Add(interval)
 
 				log.Debug(fmt.Sprintf("kaddb record %v (PO%03d:%d) selected as candidate connection %v. seen at %v (%v ago), selectable since %v, retry after %v (in %v)", node.Addr, po, cursor, rounds, node.Seen, delta, node.After, after, interval))
diff --git a/swarm/network/protocol.go b/swarm/network/protocol.go
index 2f880df570..a418c1dbbd 100644
--- a/swarm/network/protocol.go
+++ b/swarm/network/protocol.go
@@ -309,7 +309,7 @@ func (self *bzz) handleStatus() (err error) {
 		Version:   uint64(Version),
 		ID:        "honey",
 		Addr:      self.selfAddr(),
-		NetworkId: uint64(self.NetworkId),
+		NetworkId: self.NetworkId,
 		Swap: &bzzswap.SwapProfile{
 			Profile:    self.swapParams.Profile,
 			PayProfile: self.swapParams.PayProfile,
diff --git a/swarm/network/syncer.go b/swarm/network/syncer.go
index a3814e4232..d76af022c1 100644
--- a/swarm/network/syncer.go
+++ b/swarm/network/syncer.go
@@ -378,7 +378,7 @@ func (self *syncer) syncHistory(state *syncState) chan interface{} {
 				}
 				select {
 				// blocking until history channel is read from
-				case history <- storage.Key(key):
+				case history <- key:
 					n++
 					log.Trace(fmt.Sprintf("syncer[%v]: history: %v (%v keys)", self.key.Log(), key.Log(), n))
 					state.Latest = key
diff --git a/swarm/storage/chunker.go b/swarm/storage/chunker.go
index 8c0d62cbe2..98cd6e75ea 100644
--- a/swarm/storage/chunker.go
+++ b/swarm/storage/chunker.go
@@ -205,9 +205,9 @@ func (self *TreeChunker) split(depth int, treeSize int64, key Key, data io.Reade
 	}
 	// dept > 0
 	// intermediate chunk containing child nodes hashes
-	branchCnt := int64((size + treeSize - 1) / treeSize)
+	branchCnt := (size + treeSize - 1) / treeSize
 
-	var chunk []byte = make([]byte, branchCnt*self.hashSize+8)
+	var chunk = make([]byte, branchCnt*self.hashSize+8)
 	var pos, i int64
 
 	binary.LittleEndian.PutUint64(chunk[0:8], uint64(size))
diff --git a/swarm/storage/memstore.go b/swarm/storage/memstore.go
index 155dd00882..3cb25ac625 100644
--- a/swarm/storage/memstore.go
+++ b/swarm/storage/memstore.go
@@ -78,7 +78,7 @@ type memTree struct {
 func newMemTree(b uint, parent *memTree, pidx uint) (node *memTree) {
 	node = new(memTree)
 	node.bits = b
-	node.width = 1 << uint(b)
+	node.width = 1 << b
 	node.subtree = make([]*memTree, node.width)
 	node.access = make([]uint64, node.width-1)
 	node.parent = parent
diff --git a/swarm/storage/pyramid.go b/swarm/storage/pyramid.go
index 42b83583d4..5de385dcbe 100644
--- a/swarm/storage/pyramid.go
+++ b/swarm/storage/pyramid.go
@@ -327,7 +327,7 @@ func (self *PyramidChunker) loadTree(chunkLevel [][]*TreeEntry, key Key, chunkC
 	// Add the root chunk entry
 	branchCount := int64(len(chunk.SData)-8) / self.hashSize
 	newEntry := &TreeEntry{
-		level:         int(depth - 1),
+		level:         depth - 1,
 		branchCount:   branchCount,
 		subtreeSize:   uint64(chunk.Size),
 		chunk:         chunk.SData,
@@ -352,7 +352,7 @@ func (self *PyramidChunker) loadTree(chunkLevel [][]*TreeEntry, key Key, chunkC
 				}
 				bewBranchCount := int64(len(newChunk.SData)-8) / self.hashSize
 				newEntry := &TreeEntry{
-					level:         int(lvl - 1),
+					level:         lvl - 1,
 					branchCount:   bewBranchCount,
 					subtreeSize:   uint64(newChunk.Size),
 					chunk:         newChunk.SData,
diff --git a/whisper/whisperv5/topic.go b/whisper/whisperv5/topic.go
index d1996c4604..c4ea67eefa 100644
--- a/whisper/whisperv5/topic.go
+++ b/whisper/whisperv5/topic.go
@@ -40,8 +40,8 @@ func BytesToTopic(b []byte) (t TopicType) {
 }
 
 // String converts a topic byte array to a string representation.
-func (topic *TopicType) String() string {
-	return string(common.ToHex(topic[:]))
+func (t *TopicType) String() string {
+	return common.ToHex(t[:])
 }
 
 // MarshalText returns the hex representation of t.
diff --git a/whisper/whisperv5/whisper.go b/whisper/whisperv5/whisper.go
index d09246f699..85849ccce4 100644
--- a/whisper/whisperv5/whisper.go
+++ b/whisper/whisperv5/whisper.go
@@ -171,7 +171,7 @@ func (w *Whisper) SetMaxMessageSize(size uint32) error {
 	if size > MaxMessageSize {
 		return fmt.Errorf("message size too large [%d>%d]", size, MaxMessageSize)
 	}
-	w.settings.Store(maxMsgSizeIdx, uint32(size))
+	w.settings.Store(maxMsgSizeIdx, size)
 	return nil
 }
 
diff --git a/whisper/whisperv6/topic.go b/whisper/whisperv6/topic.go
index 5ef7f69392..bf5da01e34 100644
--- a/whisper/whisperv6/topic.go
+++ b/whisper/whisperv6/topic.go
@@ -40,8 +40,8 @@ func BytesToTopic(b []byte) (t TopicType) {
 }
 
 // String converts a topic byte array to a string representation.
-func (topic *TopicType) String() string {
-	return string(common.ToHex(topic[:]))
+func (t *TopicType) String() string {
+	return common.ToHex(t[:])
 }
 
 // MarshalText returns the hex representation of t.
diff --git a/whisper/whisperv6/whisper.go b/whisper/whisperv6/whisper.go
index 553ac3f000..e2b884f3d4 100644
--- a/whisper/whisperv6/whisper.go
+++ b/whisper/whisperv6/whisper.go
@@ -171,7 +171,7 @@ func (w *Whisper) SetMaxMessageSize(size uint32) error {
 	if size > MaxMessageSize {
 		return fmt.Errorf("message size too large [%d>%d]", size, MaxMessageSize)
 	}
-	w.settings.Store(maxMsgSizeIdx, uint32(size))
+	w.settings.Store(maxMsgSizeIdx, size)
 	return nil
 }