diff --git a/src/circuit/client.ts b/src/circuit/client.ts
index 9ffaa0028e..568ad1f6fb 100644
--- a/src/circuit/client.ts
+++ b/src/circuit/client.ts
@@ -22,7 +22,7 @@ import { PeerSet, PeerMap, PeerList } from '@libp2p/peer-collections'
 
 const log = logger('libp2p:circuit:client')
 
-const noop = () => {}
+const noop = (): void => {}
 
 /**
  * CircuitServiceInit initializes the circuit service using values
@@ -81,17 +81,17 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
     this.components.connectionManager.addEventListener('peer:connect', this._onPeerConnect)
   }
 
-  isStarted () {
+  isStarted (): boolean {
     return this.started
   }
 
-  start () {
+  start (): void {
     void this._listenOnAvailableHopRelays().catch(err => { log.error('error listening on relays', err) })
     this.started = true
   }
 
-  async stop () {
-    this.reservationMap.forEach((timer) => clearTimeout(timer))
+  async stop (): Promise<void> {
+    this.reservationMap.forEach((timer) => { clearTimeout(timer) })
     this.reservationMap.clear()
     this.relays.clear()
   }
@@ -102,7 +102,7 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
    * If the protocol is supported, check if the peer supports **HOP** and add it as a listener if
    * inside the threshold.
    */
-  async _onProtocolChange ({ peerId, protocols }: {peerId: PeerId, protocols: string[]}) {
+  async _onProtocolChange ({ peerId, protocols }: { peerId: PeerId, protocols: string[] }): Promise<void> {
     if (peerId.equals(this.components.peerId)) {
       return
     }
@@ -151,11 +151,11 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
    * Handle case when peer connects. If we already have the peer in the protobook,
    * we treat this event as an `onProtocolChange`.
    */
-  _onPeerConnect ({ detail: connection }: CustomEvent<Connection>) {
+  _onPeerConnect ({ detail: connection }: CustomEvent<Connection>): void {
     void this.components.peerStore.protoBook.get(connection.remotePeer)
       .then((protocols) => {
         void this._onProtocolChange({ peerId: connection.remotePeer, protocols })
-          .catch((err) => log.error('handling reconnect failed', err))
+          .catch((err) => { log.error('handling reconnect failed', err) })
       },
       (err) => {
         // this is not necessarily an error as we will only have the protocols stored
@@ -167,7 +167,7 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
   /**
    * Peer disconnects
    */
-  _onPeerDisconnected (evt: CustomEvent<Connection>) {
+  _onPeerDisconnected (evt: CustomEvent<Connection>): void {
     const connection = evt.detail
     const peerId = connection.remotePeer
     clearTimeout(this.reservationMap.get(peerId))
@@ -238,11 +238,11 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
   /**
    * Remove listen relay
    */
-  async _removeListenRelay (PeerId: PeerId) {
+  async _removeListenRelay (PeerId: PeerId): Promise<void> {
     const recheck = this.relays.has(PeerId)
     this.relays.delete(PeerId)
     if (recheck) {
-      // TODO: this should be responsibility of the connMgr
+      // TODO: this should be responsibility of the connMgr https://github.com/libp2p/js-libp2p/issues/1610
       await this._listenOnAvailableHopRelays(new PeerList([PeerId]))
     }
   }
@@ -254,7 +254,7 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
    * 2. Dial and try to listen on the peers we know that support hop but are not connected.
    * 3. Search the network.
    */
-  async _listenOnAvailableHopRelays (peersToIgnore: PeerList = new PeerList([])) {
+  async _listenOnAvailableHopRelays (peersToIgnore: PeerList = new PeerList([])): Promise<void> {
     // Check if already listening on enough relays
     if (this.relays.size >= this.maxReservations) {
       return
@@ -321,7 +321,7 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
     }
   }
 
-  async _tryToListenOnRelay (peerId: PeerId) {
+  async _tryToListenOnRelay (peerId: PeerId): Promise<void> {
     try {
       if (peerId.equals(this.components.peerId)) {
         log.trace('Skipping dialling self %p', peerId.toString())
@@ -335,7 +335,7 @@ export class RelayReservationManager extends EventEmitter<RelayReservationManage
     }
   }
 
-  private readonly createOrRefreshReservation = async (peerId: PeerId) => {
+  private readonly createOrRefreshReservation = async (peerId: PeerId): Promise<void> => {
     try {
       const connections = this.components.connectionManager.getConnections(peerId)
 
diff --git a/src/circuit/hop.ts b/src/circuit/hop.ts
index a93c3128ba..cf6b694ced 100644
--- a/src/circuit/hop.ts
+++ b/src/circuit/hop.ts
@@ -87,7 +87,7 @@ async function handleReserve ({ connection, stream: pbstr, relayPeer, relayAddrs
     return
   }
 
-  const result = await reservationStore.reserve(connection.remotePeer, connection.remoteAddr)
+  const result = reservationStore.reserve(connection.remotePeer, connection.remoteAddr)
 
   if (result.status !== Status.OK) {
     hopstr.write({ type: HopMessage.Type.STATUS, status: result.status })
@@ -105,12 +105,12 @@ async function handleReserve ({ connection, stream: pbstr, relayPeer, relayAddrs
       type: HopMessage.Type.STATUS,
       status: Status.OK,
       reservation: await makeReservation(relayAddrs, relayPeer, connection.remotePeer, BigInt(result.expire ?? 0)),
-      limit: (await reservationStore.get(relayPeer))?.limit
+      limit: reservationStore.get(relayPeer)?.limit
     })
     log('sent confirmation response to %s', connection.remotePeer)
   } catch (err) {
     log.error('failed to send confirmation response to %s', connection.remotePeer)
-    await reservationStore.removeReservation(connection.remotePeer)
+    reservationStore.removeReservation(connection.remotePeer)
   }
 }
 
@@ -138,12 +138,12 @@ async function handleConnect (options: HopProtocolOptions): Promise<void> {
     const status = await acl.allowConnect(connection.remotePeer, connection.remoteAddr, dstPeer)
     if (status !== Status.OK) {
       log.error('hop connect denied for %s with status %s', connection.remotePeer, status)
-      hopstr.write({ type: HopMessage.Type.STATUS, status: status })
+      hopstr.write({ type: HopMessage.Type.STATUS, status })
       return
     }
   }
 
-  if (!await reservationStore.hasReservation(dstPeer)) {
+  if (!reservationStore.hasReservation(dstPeer)) {
     log.error('hop connect denied for %s with status %s', connection.remotePeer, Status.NO_RESERVATION)
     hopstr.write({ type: HopMessage.Type.STATUS, status: Status.NO_RESERVATION })
     return
@@ -179,9 +179,9 @@ async function handleConnect (options: HopProtocolOptions): Promise<void> {
   const sourceStream = stream.unwrap()
 
   log('connection to destination established, short circuiting streams...')
-  const limit = (await reservationStore.get(dstPeer))?.limit
+  const limit = reservationStore.get(dstPeer)?.limit
   // Short circuit the two streams to create the relayed connection
-  return createLimitedRelay(sourceStream, destinationStream, limit)
+  createLimitedRelay(sourceStream, destinationStream, limit)
 }
 
 async function makeReservation (
diff --git a/src/circuit/interfaces.ts b/src/circuit/interfaces.ts
index 3c0d428c68..9bb582b551 100644
--- a/src/circuit/interfaces.ts
+++ b/src/circuit/interfaces.ts
@@ -11,7 +11,7 @@ export interface Reservation {
 }
 
 export interface ReservationStore {
-  reserve: (peer: PeerId, addr: Multiaddr, limit?: Limit) => {status: ReservationStatus, expire?: number}
+  reserve: (peer: PeerId, addr: Multiaddr, limit?: Limit) => { status: ReservationStatus, expire?: number }
   removeReservation: (peer: PeerId) => void
   hasReservation: (dst: PeerId) => boolean
   get: (peer: PeerId) => Reservation | undefined
diff --git a/src/circuit/listener.ts b/src/circuit/listener.ts
index 7a6422729d..09af1a5147 100644
--- a/src/circuit/listener.ts
+++ b/src/circuit/listener.ts
@@ -54,7 +54,7 @@ export function createListener (options: ListenerOptions): Listener {
    *
    * @returns {Multiaddr[]}
    */
-  function getAddrs () {
+  function getAddrs (): Multiaddr[] {
     const addrs = []
     for (const addr of listeningAddrs.values()) {
       addrs.push(addr)
@@ -63,7 +63,7 @@ export function createListener (options: ListenerOptions): Listener {
   }
 
   const listener: Listener = Object.assign(new EventEmitter(), {
-    close: async () => await Promise.resolve(),
+    close: async () => { await Promise.resolve() },
     listen,
     getAddrs
   })
diff --git a/src/circuit/relay.ts b/src/circuit/relay.ts
index 6ec8e3e015..9e163191bb 100644
--- a/src/circuit/relay.ts
+++ b/src/circuit/relay.ts
@@ -39,14 +39,14 @@ export class Relay implements Startable {
     this._advertiseService = this._advertiseService.bind(this)
   }
 
-  isStarted () {
+  isStarted (): boolean {
     return this.started
   }
 
   /**
    * Start Relay service
    */
-  async start () {
+  async start (): Promise<void> {
     // Advertise service if HOP enabled and advertising enabled
     if (this.init.hop.enabled === true && this.init.advertise.enabled === true) {
       this.timeout = setDelayedInterval(
@@ -60,7 +60,7 @@ export class Relay implements Startable {
   /**
    * Stop Relay service
    */
-  async stop () {
+  async stop (): Promise<void> {
     try {
       clearDelayedInterval(this.timeout)
     } catch (err) { }
@@ -71,7 +71,7 @@ export class Relay implements Startable {
   /**
    * Advertise hop relay service in the network.
    */
-  async _advertiseService () {
+  async _advertiseService (): Promise<void> {
     try {
       const cid = await namespaceToCid(RELAY_RENDEZVOUS_NS)
       await this.components.contentRouting.provide(cid)
diff --git a/src/circuit/reservation-store.ts b/src/circuit/reservation-store.ts
index b48cbff8b9..d70a4ea8fb 100644
--- a/src/circuit/reservation-store.ts
+++ b/src/circuit/reservation-store.ts
@@ -38,7 +38,7 @@ export type ReservationStoreOptions = RecursivePartial<ReservationStoreInit>
 
 export class ReservationStore implements IReservationStore, Startable {
   private readonly reservations = new PeerMap<Reservation>()
-  private _started = false;
+  private _started = false
   private interval: any
   private readonly init: ReservationStoreInit
 
@@ -53,11 +53,11 @@ export class ReservationStore implements IReservationStore, Startable {
     }
   }
 
-  isStarted () {
+  isStarted (): boolean {
     return this._started
   }
 
-  start () {
+  start (): void {
     if (this._started) {
       return
     }
@@ -75,7 +75,7 @@ export class ReservationStore implements IReservationStore, Startable {
     )
   }
 
-  stop () {
+  stop (): void {
     clearInterval(this.interval)
   }
 
diff --git a/src/circuit/reservation-voucher.ts b/src/circuit/reservation-voucher.ts
index 9979ae0692..38e6a26450 100644
--- a/src/circuit/reservation-voucher.ts
+++ b/src/circuit/reservation-voucher.ts
@@ -22,7 +22,7 @@ export class ReservationVoucherRecord implements Record {
     this.expiration = expiration
   }
 
-  marshal () {
+  marshal (): Uint8Array {
     return ReservationVoucher.encode({
       relay: this.relay.toBytes(),
       peer: this.peer.toBytes(),
@@ -30,7 +30,7 @@ export class ReservationVoucherRecord implements Record {
     })
   }
 
-  equals (other: Record) {
+  equals (other: Record): boolean {
     if (!(other instanceof ReservationVoucherRecord)) {
       return false
     }
diff --git a/src/circuit/stop.ts b/src/circuit/stop.ts
index e650fe6683..d791c0627e 100644
--- a/src/circuit/stop.ts
+++ b/src/circuit/stop.ts
@@ -30,7 +30,7 @@ export async function handleStop ({
   connection,
   request,
   pbstr
-}: HandleStopOptions) {
+}: HandleStopOptions): Promise<Stream | undefined> {
   const stopstr = pbstr.pb(StopMessage)
   log('new circuit relay v2 stop stream from %s', connection.remotePeer)
   // Validate the STOP request has the required input
@@ -45,7 +45,7 @@ export async function handleStop ({
     return
   }
 
-  // TODO: go-libp2p marks connection transient if there is limit field present in request.
+  // TODO: go-libp2p marks connection transient if there is limit field present in request. Depends on https://github.com/libp2p/js-libp2p/issues/1611
   // Cannot find any reference to transient connections in js-libp2p
 
   stopstr.write({ type: StopMessage.Type.STATUS, status: Status.OK })
diff --git a/src/circuit/transport.ts b/src/circuit/transport.ts
index f1957dd855..0283519f1b 100644
--- a/src/circuit/transport.ts
+++ b/src/circuit/transport.ts
@@ -69,7 +69,7 @@ export class Circuit implements Transport, Startable {
     this._started = false
   }
 
-  isStarted () {
+  isStarted (): boolean {
     return this._started
   }
 
@@ -102,11 +102,11 @@ export class Circuit implements Transport, Startable {
       })
 
     if (this._init.hop.enabled === true) {
-      void this.reservationStore.start()
+      this.reservationStore.start()
     }
   }
 
-  async stop () {
+  async stop (): Promise<void> {
     if (this._init.hop.enabled === true) {
       this.reservationStore.stop()
       await this.components.registrar.unhandle(RELAY_V2_HOP_CODEC)
@@ -118,11 +118,11 @@ export class Circuit implements Transport, Startable {
     return true
   }
 
-  get [Symbol.toStringTag] () {
+  get [Symbol.toStringTag] (): 'libp2p/circuit-relay-v2' {
     return 'libp2p/circuit-relay-v2'
   }
 
-  async onHop ({ connection, stream }: IncomingStreamData) {
+  async onHop ({ connection, stream }: IncomingStreamData): Promise<void> {
     log('received circuit v2 hop protocol stream from %s', connection.remotePeer)
 
     const hopTimeoutPromise = pDefer()
@@ -165,7 +165,7 @@ export class Circuit implements Transport, Startable {
     }
   }
 
-  async onStop ({ connection, stream }: IncomingStreamData) {
+  async onStop ({ connection, stream }: IncomingStreamData): Promise<void> {
     const pbstr = pbStream(stream)
     const request = await pbstr.readPB(CircuitV2.StopMessage)
     log('received circuit v2 stop protocol request from %s', connection.remotePeer)
@@ -248,7 +248,7 @@ export class Circuit implements Transport, Startable {
       destinationAddr, relayAddr, ma,
       disconnectOnFailure
     }: ConnectOptions
-  ) {
+  ): Promise<Connection> {
     try {
       const pbstr = pbStream(stream)
       const hopstr = pbstr.pb(CircuitV2.HopMessage)
diff --git a/src/circuit/utils.ts b/src/circuit/utils.ts
index bad7597ba4..479febc4b7 100644
--- a/src/circuit/utils.ts
+++ b/src/circuit/utils.ts
@@ -8,17 +8,17 @@ import type { Stream } from '@libp2p/interface-connection'
 
 const log = logger('libp2p:circuit:v2:util')
 
-const doRelay = (src: Stream, dst: Stream) => {
+const doRelay = (src: Stream, dst: Stream): void => {
   queueMicrotask(() => {
-    void dst.sink(src.source).catch(err => log.error('error while relating streams:', err))
+    void dst.sink(src.source).catch(err => { log.error('error while relating streams:', err) })
   })
 
   queueMicrotask(() => {
-    void src.sink(dst.source).catch(err => log.error('error while relaying streams:', err))
+    void src.sink(dst.source).catch(err => { log.error('error while relaying streams:', err) })
   })
 }
 
-export function createLimitedRelay (source: Stream, destination: Stream, limit?: Limit) {
+export function createLimitedRelay (source: Stream, destination: Stream, limit?: Limit): void {
   // trivial case
   if (limit == null) {
     doRelay(source, destination)