diff --git a/.aegir.js b/.aegir.js
index 603bcc8e..7ba3e1fb 100644
--- a/.aegir.js
+++ b/.aegir.js
@@ -49,5 +49,11 @@ module.exports = {
   hooks: {
     pre: before,
     post: after
+  },
+  webpack: {
+    node: {
+      // needed by bcrypto
+      Buffer: true
+    }
   }
 }
diff --git a/doc/API.md b/doc/API.md
index 9deb5b1e..6ba854cf 100644
--- a/doc/API.md
+++ b/doc/API.md
@@ -585,7 +585,7 @@ Writes a value to a key in the DHT.
 | Name | Type | Description |
 |------|------|-------------|
 | key | `string` | key to add to the dht |
-| value | `Buffer` | value to add to the dht |
+| value | `Uint8Array` | value to add to the dht |
 | [options] | `object` | put options |
 | [options.minPeers] | `number` | minimum number of peers required to successfully put (default: closestPeers.length) |
 
@@ -600,7 +600,7 @@ Writes a value to a key in the DHT.
 ```js
 // ...
 const key = '/key'
-const value = Buffer.from('oh hello there')
+const value = uint8ArrayFromString('oh hello there')
 
 await libp2p.contentRouting.put(key, value)
 ```
@@ -623,7 +623,7 @@ Queries the DHT for a value stored for a given key.
 
 | Type | Description |
 |------|-------------|
-| `Promise<Buffer>` | Value obtained from the DHT |
+| `Promise<Uint8Array>` | Value obtained from the DHT |
 
 #### Example
 
@@ -653,7 +653,7 @@ Queries the DHT for the n values stored for the given key (without sorting).
 
 | Type | Description |
 |------|-------------|
-| `Promise<Array<{from: PeerId, val: Buffer}>>` | Array of records obtained from the DHT |
+| `Promise<Array<{from: PeerId, val: Uint8Array}>>` | Array of records obtained from the DHT |
 
 #### Example
 
@@ -970,7 +970,7 @@ Delete the provided peer from the book.
 ```js
 peerStore.metadataBook.delete(peerId)
 // false
-peerStore.metadataBook.set(peerId, 'nickname', Buffer.from('homePeer'))
+peerStore.metadataBook.set(peerId, 'nickname', uint8ArrayFromString('homePeer'))
 peerStore.metadataBook.delete(peerId)
 // true
 ```
@@ -999,7 +999,7 @@ Deletes the provided peer metadata key-value pair from the book.
 ```js
 peerStore.metadataBook.deleteValue(peerId, 'location')
 // false
-peerStore.metadataBook.set(peerId, 'location', Buffer.from('Berlin'))
+peerStore.metadataBook.set(peerId, 'location', uint8ArrayFromString('Berlin'))
 peerStore.metadataBook.deleteValue(peerId, 'location')
 // true
 ```
@@ -1020,14 +1020,14 @@ Get the known metadata of a provided peer.
 
 | Type | Description |
 |------|-------------|
-| `Map<string, Buffer>` | Peer Metadata |
+| `Map<string, Uint8Array>` | Peer Metadata |
 
 #### Example
 
 ```js
 peerStore.metadataBook.get(peerId)
 // undefined
-peerStore.metadataBook.set(peerId, 'location', Buffer.from('Berlin'))
+peerStore.metadataBook.set(peerId, 'location', uint8ArrayFromString('Berlin'))
 peerStore.metadataBook.get(peerId)
 // Metadata Map
 ```
@@ -1049,14 +1049,14 @@ Get specific metadata of a provided peer.
 
 | Type | Description |
 |------|-------------|
-| `Map<string, Buffer>` | Peer Metadata |
+| `Map<string, Uint8Array>` | Peer Metadata |
 
 #### Example
 
 ```js
 peerStore.metadataBook.getValue(peerId, 'location')
 // undefined
-peerStore.metadataBook.set(peerId, 'location', Buffer.from('Berlin'))
+peerStore.metadataBook.set(peerId, 'location', uint8ArrayFromString('Berlin'))
 peerStore.metadataBook.getValue(peerId, 'location')
 // Metadata Map
 ```
@@ -1073,7 +1073,7 @@ Set known metadata of a given `peerId`.
 |------|------|-------------|
 | peerId | [`PeerId`][peer-id] | peerId to set |
 | key | `string` | key of the metadata value to store |
-| value | `Buffer` | metadata value to store |
+| value | `Uint8Array` | metadata value to store |
 
 #### Returns
 
@@ -1084,7 +1084,7 @@ Set known metadata of a given `peerId`.
 #### Example
 
 ```js
-peerStore.metadataBook.set(peerId, 'location', Buffer.from('Berlin'))
+peerStore.metadataBook.set(peerId, 'location', uint8ArrayFromString('Berlin'))
 ```
 
 ### peerStore.protoBook.delete
@@ -1308,7 +1308,7 @@ Publishes messages to the given topics.
 | Name | Type | Description |
 |------|------|-------------|
 | topic | `string` | topic to publish |
-| data | `Buffer` | data to publish  |
+| data | `Uint8Array` | data to publish  |
 
 #### Returns
 
@@ -1320,7 +1320,7 @@ Publishes messages to the given topics.
 
 ```js
 const topic = 'topic'
-const data = Buffer.from('data')
+const data = uint8ArrayFromString('data')
 
 await libp2p.pubsub.publish(topic, data)
 ```
@@ -1336,7 +1336,7 @@ Subscribes the given handler to a pubsub topic.
 | Name | Type | Description |
 |------|------|-------------|
 | topic | `string` | topic to subscribe |
-| handler | `function({ from: string, data: Buffer, seqno: Buffer, topicIDs: Array<string>, signature: Buffer, key: Buffer })` | handler for new data on topic |
+| handler | `function({ from: string, data: Uint8Array, seqno: Uint8Array, topicIDs: Array<string>, signature: Uint8Array, key: Uint8Array })` | handler for new data on topic |
 
 #### Returns
 
@@ -1679,19 +1679,19 @@ Encrypt protected data using the Cryptographic Message Syntax (CMS).
 | Name | Type | Description |
 |------|------|-------------|
 | name | `string` | The local key name. |
-| data | `Buffer` | The data to encrypt. |
+| data | `Uint8Array` | The data to encrypt. |
 
 #### Returns
 
 | Type | Description |
 |------|-------------|
-| `Promise<Buffer>` | Encrypted data as a PKCS #7 message in DER. |
+| `Promise<Uint8Array>` | Encrypted data as a PKCS #7 message in DER. |
 
 #### Example
 
 ```js
 const keyInfo = await libp2p.keychain.createKey('keyTest', 'rsa', 4096)
-const enc = await libp2p.keychain.cms.encrypt('keyTest', Buffer.from('data'))
+const enc = await libp2p.keychain.cms.encrypt('keyTest', uint8ArrayFromString('data'))
 ```
 
 ### keychain.cms.decrypt
@@ -1711,13 +1711,13 @@ The keychain must contain one of the keys used to encrypt the data.  If none of
 
 | Type | Description |
 |------|-------------|
-| `Promise<Buffer>` | Decrypted data. |
+| `Promise<Uint8Array>` | Decrypted data. |
 
 #### Example
 
 ```js
 const keyInfo = await libp2p.keychain.createKey('keyTest', 'rsa', 4096)
-const enc = await libp2p.keychain.cms.encrypt('keyTest', Buffer.from('data'))
+const enc = await libp2p.keychain.cms.encrypt('keyTest', uint8ArrayFromString('data'))
 const decData = await libp2p.keychain.cms.decrypt(enc)
 ```
 
diff --git a/examples/chat/src/stream.js b/examples/chat/src/stream.js
index 30385b97..de888dc7 100644
--- a/examples/chat/src/stream.js
+++ b/examples/chat/src/stream.js
@@ -3,6 +3,7 @@
 
 const pipe = require('it-pipe')
 const lp = require('it-length-prefixed')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 function stdinToStream(stream) {
   // Read utf-8 from stdin
@@ -28,7 +29,7 @@ function streamToConsole(stream) {
       // For each chunk of data
       for await (const msg of source) {
         // Output the data as a utf8 string
-        console.log('> ' + msg.toString('utf8').replace('\n', ''))
+        console.log('> ' + uint8ArrayToString(msg).replace('\n', ''))
       }
     }
   )
diff --git a/examples/pnet/index.js b/examples/pnet/index.js
index 2f45d576..1e766d53 100644
--- a/examples/pnet/index.js
+++ b/examples/pnet/index.js
@@ -1,18 +1,17 @@
 /* eslint no-console: ["off"] */
 'use strict'
 
-const { Buffer } = require('buffer')
 const { generate } = require('libp2p/src/pnet')
 const privateLibp2pNode = require('./libp2p-node')
 
 const pipe = require('it-pipe')
 
-// Create a buffer and write the swarm key to it
-const swarmKey = Buffer.alloc(95)
+// Create a Uint8Array and write the swarm key to it
+const swarmKey = new Uint8Array(95)
 generate(swarmKey)
 
 // This key is for testing a different key not working
-const otherSwarmKey = Buffer.alloc(95)
+const otherSwarmKey = new Uint8Array(95)
 generate(otherSwarmKey)
 
 ;(async () => {
diff --git a/examples/pnet/libp2p-node.js b/examples/pnet/libp2p-node.js
index 7bd0d16a..849d47d3 100644
--- a/examples/pnet/libp2p-node.js
+++ b/examples/pnet/libp2p-node.js
@@ -11,7 +11,7 @@ const Protector = require('libp2p/src/pnet')
  * privateLibp2pNode returns a libp2p node function that will use the swarm
  * key with the given `swarmKey` to create the Protector
  *
- * @param {Buffer} swarmKey
+ * @param {Uint8Array} swarmKey
  * @returns {Promise<libp2p>} Returns a libp2pNode function for use in IPFS creation
  */
 const privateLibp2pNode = async (swarmKey) => {
diff --git a/examples/pubsub/1.js b/examples/pubsub/1.js
index 21399541..2c223715 100644
--- a/examples/pubsub/1.js
+++ b/examples/pubsub/1.js
@@ -1,13 +1,13 @@
 /* eslint-disable no-console */
 'use strict'
 
-const { Buffer } = require('buffer')
 const Libp2p = require('../../')
 const TCP = require('libp2p-tcp')
 const Mplex = require('libp2p-mplex')
 const { NOISE } = require('libp2p-noise')
 const SECIO = require('libp2p-secio')
 const Gossipsub = require('libp2p-gossipsub')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const createNode = async () => {
   const node = await Libp2p.create({
@@ -48,6 +48,6 @@ const createNode = async () => {
 
   // node2 publishes "news" every second
   setInterval(() => {
-    node2.pubsub.publish(topic, Buffer.from('Bird bird bird, bird is the word!'))
+    node2.pubsub.publish(topic, uint8ArrayFromString('Bird bird bird, bird is the word!'))
   }, 1000)
 })()
diff --git a/examples/pubsub/README.md b/examples/pubsub/README.md
index f471b7ad..0ed99c52 100644
--- a/examples/pubsub/README.md
+++ b/examples/pubsub/README.md
@@ -57,7 +57,7 @@ await node2.pubsub.subscribe(topic, (msg) => {
 
 // node2 publishes "news" every second
 setInterval(() => {
-  node2.pubsub.publish(topic, Buffer.from('Bird bird bird, bird is the word!'))
+  node2.pubsub.publish(topic, uint8ArrayFromString('Bird bird bird, bird is the word!'))
 }, 1000)
 ```
 
diff --git a/examples/pubsub/message-filtering/1.js b/examples/pubsub/message-filtering/1.js
index eba3c647..a6f63fe1 100644
--- a/examples/pubsub/message-filtering/1.js
+++ b/examples/pubsub/message-filtering/1.js
@@ -1,13 +1,13 @@
 /* eslint-disable no-console */
 'use strict'
 
-const { Buffer } = require('buffer')
 const Libp2p = require('../../../')
 const TCP = require('libp2p-tcp')
 const Mplex = require('libp2p-mplex')
 const { NOISE } = require('libp2p-noise')
 const SECIO = require('libp2p-secio')
 const Gossipsub = require('libp2p-gossipsub')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const createNode = async () => {
   const node = await Libp2p.create({
@@ -73,7 +73,7 @@ const createNode = async () => {
   // car is not a fruit !
   setInterval(() => {
     console.log('############## fruit ' + myFruits[count] + ' ##############')
-    node1.pubsub.publish(topic, Buffer.from(myFruits[count]))
+    node1.pubsub.publish(topic, uint8ArrayFromString(myFruits[count]))
     count++
     if (count == myFruits.length) {
       count = 0
diff --git a/examples/pubsub/message-filtering/README.md b/examples/pubsub/message-filtering/README.md
index 8f7de5be..b59b26a0 100644
--- a/examples/pubsub/message-filtering/README.md
+++ b/examples/pubsub/message-filtering/README.md
@@ -79,7 +79,7 @@ const myFruits = ['banana', 'apple', 'car', 'orange'];
 
 setInterval(() => {
   console.log('############## fruit ' + myFruits[count] + ' ##############')
-  node1.pubsub.publish(topic, Buffer.from(myFruits[count]))
+  node1.pubsub.publish(topic, new TextEncoder().encode(myFruits[count]))
   count++
   if (count == myFruits.length) {
     count = 0
diff --git a/package.json b/package.json
index 7c1358ae..9d0bea10 100644
--- a/package.json
+++ b/package.json
@@ -50,7 +50,7 @@
     "err-code": "^2.0.0",
     "events": "^3.1.0",
     "hashlru": "^2.3.0",
-    "interface-datastore": "^1.0.4",
+    "interface-datastore": "^2.0.0",
     "ipfs-utils": "^2.2.0",
     "it-all": "^1.0.1",
     "it-buffer": "^0.1.2",
@@ -58,69 +58,67 @@
     "it-length-prefixed": "^3.0.1",
     "it-pipe": "^1.1.0",
     "it-protocol-buffers": "^0.2.0",
-    "libp2p-crypto": "^0.17.9",
-    "libp2p-interfaces": "^0.3.1",
-    "libp2p-utils": "^0.1.2",
-    "mafmt": "^7.0.0",
+    "libp2p-crypto": "^0.18.0",
+    "libp2p-interfaces": "^0.5.0",
+    "libp2p-utils": "^0.2.0",
+    "mafmt": "^8.0.0",
     "merge-options": "^2.0.0",
     "moving-average": "^1.0.0",
-    "multiaddr": "^7.4.3",
+    "multiaddr": "^8.0.0",
     "multicodec": "^1.0.2",
-    "multistream-select": "^0.15.0",
+    "multistream-select": "^1.0.0",
     "mutable-proxy": "^1.0.0",
     "node-forge": "^0.9.1",
     "p-any": "^3.0.0",
     "p-fifo": "^1.0.0",
     "p-settle": "^4.0.1",
-    "peer-id": "^0.13.11",
-    "protons": "^1.0.1",
+    "peer-id": "^0.14.0",
+    "protons": "^2.0.0",
     "retimer": "^2.0.0",
     "sanitize-filename": "^1.6.3",
-    "streaming-iterables": "^4.1.0",
-    "timeout-abort-controller": "^1.0.0",
+    "streaming-iterables": "^5.0.2",
+    "timeout-abort-controller": "^1.1.1",
     "varint": "^5.0.0",
     "xsalsa20": "^1.0.2"
   },
   "devDependencies": {
     "@nodeutils/defaults-deep": "^1.1.0",
     "abortable-iterator": "^3.0.0",
-    "aegir": "^22.0.0",
+    "aegir": "^26.0.0",
     "chai": "^4.2.0",
     "chai-as-promised": "^7.1.1",
     "chai-bytes": "^0.1.2",
     "chai-string": "^1.5.0",
-    "cids": "^0.8.0",
-    "datastore-fs": "^1.1.0",
-    "datastore-level": "^1.1.0",
+    "cids": "^1.0.0",
     "delay": "^4.3.0",
     "dirty-chai": "^2.0.1",
-    "interop-libp2p": "^0.1.0",
-    "ipfs-http-client": "^44.0.0",
+    "interop-libp2p": "^0.2.0",
+    "ipfs-http-client": "^46.0.0",
     "it-concat": "^1.0.0",
     "it-pair": "^1.0.0",
     "it-pushable": "^1.4.0",
-    "level": "^6.0.1",
-    "libp2p-bootstrap": "^0.11.0",
-    "libp2p-delegated-content-routing": "^0.5.0",
-    "libp2p-delegated-peer-routing": "^0.5.0",
-    "libp2p-floodsub": "^0.21.0",
-    "libp2p-gossipsub": "^0.4.6",
-    "libp2p-kad-dht": "^0.19.1",
-    "libp2p-mdns": "^0.14.1",
-    "libp2p-mplex": "^0.9.5",
-    "libp2p-noise": "^1.1.1",
-    "libp2p-secio": "^0.12.4",
-    "libp2p-tcp": "^0.14.1",
-    "libp2p-webrtc-star": "^0.18.0",
-    "libp2p-websockets": "^0.13.1",
-    "multihashes": "^0.4.19",
-    "nock": "^12.0.3",
+    "libp2p-bootstrap": "^0.12.0",
+    "libp2p-delegated-content-routing": "^0.6.0",
+    "libp2p-delegated-peer-routing": "^0.6.0",
+    "libp2p-floodsub": "^0.22.0",
+    "libp2p-gossipsub": "^0.5.0",
+    "libp2p-kad-dht": "^0.20.0",
+    "libp2p-mdns": "^0.15.0",
+    "libp2p-mplex": "^0.10.0",
+    "libp2p-noise": "^2.0.0",
+    "libp2p-secio": "^0.13.1",
+    "libp2p-tcp": "^0.15.1",
+    "libp2p-webrtc-star": "^0.19.0",
+    "libp2p-websockets": "^0.14.0",
+    "multihashes": "^3.0.1",
+    "nock": "^13.0.3",
     "p-defer": "^3.0.0",
     "p-times": "^3.0.0",
     "p-wait-for": "^3.1.0",
     "promisify-es6": "^1.0.3",
     "rimraf": "^3.0.2",
-    "sinon": "^9.0.2"
+    "sinon": "^9.0.2",
+    "uint8arrays": "^1.1.0"
   },
   "contributors": [
     "David Dias <daviddias.p@gmail.com>",
diff --git a/src/circuit/index.js b/src/circuit/index.js
index 904e9ad2..baf10e37 100644
--- a/src/circuit/index.js
+++ b/src/circuit/index.js
@@ -122,11 +122,11 @@ class Circuit {
           type: CircuitPB.Type.HOP,
           srcPeer: {
             id: this.peerId.toBytes(),
-            addrs: this._libp2p.multiaddrs.map(addr => addr.buffer)
+            addrs: this._libp2p.multiaddrs.map(addr => addr.bytes)
           },
           dstPeer: {
             id: destinationPeer.toBytes(),
-            addrs: [multiaddr(destinationAddr).buffer]
+            addrs: [multiaddr(destinationAddr).bytes]
           }
         }
       })
diff --git a/src/content-routing.js b/src/content-routing.js
index 71b2290e..dcf549e7 100644
--- a/src/content-routing.js
+++ b/src/content-routing.js
@@ -64,8 +64,8 @@ module.exports = (node) => {
 
     /**
      * Store the given key/value pair in the DHT.
-     * @param {Buffer} key
-     * @param {Buffer} value
+     * @param {Uint8Array} key
+     * @param {Uint8Array} value
      * @param {Object} [options] - put options
      * @param {number} [options.minPeers] - minimum number of peers required to successfully put
      * @returns {Promise<void>}
@@ -81,10 +81,10 @@ module.exports = (node) => {
     /**
      * Get the value to the given key.
      * Times out after 1 minute by default.
-     * @param {Buffer} key
+     * @param {Uint8Array} key
      * @param {Object} [options] - get options
      * @param {number} [options.timeout] - optional timeout (default: 60000)
-     * @returns {Promise<{from: PeerId, val: Buffer}>}
+     * @returns {Promise<{from: PeerId, val: Uint8Array}>}
      */
     async get (key, options) { // eslint-disable-line require-await
       if (!node.isStarted() || !dht.isStarted) {
@@ -96,11 +96,11 @@ module.exports = (node) => {
 
     /**
      * Get the `n` values to the given key without sorting.
-     * @param {Buffer} key
+     * @param {Uint8Array} key
      * @param {number} nVals
      * @param {Object} [options] - get options
      * @param {number} [options.timeout] - optional timeout (default: 60000)
-     * @returns {Promise<Array<{from: PeerId, val: Buffer}>>}
+     * @returns {Promise<Array<{from: PeerId, val: Uint8Array}>>}
      */
     async getMany (key, nVals, options) { // eslint-disable-line require-await
       if (!node.isStarted() || !dht.isStarted) {
diff --git a/src/identify/index.js b/src/identify/index.js
index 4e6a1570..a313ad0e 100644
--- a/src/identify/index.js
+++ b/src/identify/index.js
@@ -5,11 +5,11 @@ const log = debug('libp2p:identify')
 log.error = debug('libp2p:identify:error')
 
 const errCode = require('err-code')
-const { Buffer } = require('buffer')
 const pb = require('it-protocol-buffers')
 const lp = require('it-length-prefixed')
 const pipe = require('it-pipe')
 const { collect, take, consume } = require('streaming-iterables')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const PeerId = require('peer-id')
 const multiaddr = require('multiaddr')
@@ -32,7 +32,7 @@ const { codes } = require('../errors')
 class IdentifyService {
   /**
    * Takes the `addr` and converts it to a Multiaddr if possible
-   * @param {Buffer|String} addr
+   * @param {Uint8Array|String} addr
    * @returns {Multiaddr|null}
    */
   static getCleanMultiaddr (addr) {
@@ -91,7 +91,7 @@ class IdentifyService {
    */
   async push (connections) {
     const signedPeerRecord = await this._getSelfPeerRecord()
-    const listenAddrs = this._libp2p.multiaddrs.map((ma) => ma.buffer)
+    const listenAddrs = this._libp2p.multiaddrs.map((ma) => ma.bytes)
     const protocols = Array.from(this._protocols.keys())
 
     const pushes = connections.map(async connection => {
@@ -199,7 +199,7 @@ class IdentifyService {
     }
 
     this.peerStore.protoBook.set(id, protocols)
-    this.peerStore.metadataBook.set(id, 'AgentVersion', Buffer.from(message.agentVersion))
+    this.peerStore.metadataBook.set(id, 'AgentVersion', uint8ArrayFromString(message.agentVersion))
 
     // TODO: Track our observed address so that we can score it
     log('received observed address of %s', observedAddr)
@@ -234,7 +234,7 @@ class IdentifyService {
    * @param {Connection} options.connection
    */
   async _handleIdentify ({ connection, stream }) {
-    let publicKey = Buffer.alloc(0)
+    let publicKey = new Uint8Array(0)
     if (this.peerId.pubKey) {
       publicKey = this.peerId.pubKey.bytes
     }
@@ -245,9 +245,9 @@ class IdentifyService {
       protocolVersion: PROTOCOL_VERSION,
       agentVersion: AGENT_VERSION,
       publicKey,
-      listenAddrs: this._libp2p.multiaddrs.map((ma) => ma.buffer),
+      listenAddrs: this._libp2p.multiaddrs.map((ma) => ma.bytes),
       signedPeerRecord,
-      observedAddr: connection.remoteAddr.buffer,
+      observedAddr: connection.remoteAddr.bytes,
       protocols: Array.from(this._protocols.keys())
     })
 
@@ -311,7 +311,7 @@ class IdentifyService {
 
   /**
    * Get self signed peer record raw envelope.
-   * @return {Buffer}
+   * @return {Uint8Array}
    */
   async _getSelfPeerRecord () {
     const selfSignedPeerRecord = this.peerStore.addressBook.getRawEnvelope(this.peerId)
diff --git a/src/keychain/cms.js b/src/keychain/cms.js
index 9bec4b94..60bfd323 100644
--- a/src/keychain/cms.js
+++ b/src/keychain/cms.js
@@ -5,6 +5,8 @@ require('node-forge/lib/pbe')
 const forge = require('node-forge/lib/forge')
 const { certificateForKey, findAsync } = require('./util')
 const errcode = require('err-code')
+const uint8ArrayFromString = require('uint8arrays/from-string')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 /**
  * Cryptographic Message Syntax (aka PKCS #7)
@@ -32,15 +34,15 @@ class CMS {
   /**
    * Creates some protected data.
    *
-   * The output Buffer contains the PKCS #7 message in DER.
+   * The output Uint8Array contains the PKCS #7 message in DER.
    *
    * @param {string} name - The local key name.
-   * @param {Buffer} plain - The data to encrypt.
+   * @param {Uint8Array} plain - The data to encrypt.
    * @returns {undefined}
    */
   async encrypt (name, plain) {
-    if (!Buffer.isBuffer(plain)) {
-      throw errcode(new Error('Plain data must be a Buffer'), 'ERR_INVALID_PARAMS')
+    if (!(plain instanceof Uint8Array)) {
+      throw errcode(new Error('Plain data must be a Uint8Array'), 'ERR_INVALID_PARAMS')
     }
 
     const key = await this.keychain.findKeyByName(name)
@@ -56,7 +58,7 @@ class CMS {
 
     // convert message to DER
     const der = forge.asn1.toDer(p7.toAsn1()).getBytes()
-    return Buffer.from(der, 'binary')
+    return uint8ArrayFromString(der, 'ascii')
   }
 
   /**
@@ -65,17 +67,17 @@ class CMS {
    * The keychain must contain one of the keys used to encrypt the data.  If none of the keys
    * exists, an Error is returned with the property 'missingKeys'.  It is array of key ids.
    *
-   * @param {Buffer} cmsData - The CMS encrypted data to decrypt.
+   * @param {Uint8Array} cmsData - The CMS encrypted data to decrypt.
    * @returns {undefined}
    */
   async decrypt (cmsData) {
-    if (!Buffer.isBuffer(cmsData)) {
+    if (!(cmsData instanceof Uint8Array)) {
       throw errcode(new Error('CMS data is required'), 'ERR_INVALID_PARAMS')
     }
 
     let cms
     try {
-      const buf = forge.util.createBuffer(cmsData.toString('binary'))
+      const buf = forge.util.createBuffer(uint8ArrayToString(cmsData, 'ascii'))
       const obj = forge.asn1.fromDer(buf)
       cms = forge.pkcs7.messageFromAsn1(obj)
     } catch (err) {
@@ -115,7 +117,7 @@ class CMS {
     const pem = await this.keychain._getPrivateKey(key.name)
     const privateKey = forge.pki.decryptRsaPrivateKey(pem, this.keychain._())
     cms.decrypt(r.recipient, privateKey)
-    return Buffer.from(cms.content.getBytes(), 'binary')
+    return uint8ArrayFromString(cms.content.getBytes(), 'ascii')
   }
 }
 
diff --git a/src/keychain/index.js b/src/keychain/index.js
index ef6aac7d..d01acb68 100644
--- a/src/keychain/index.js
+++ b/src/keychain/index.js
@@ -8,6 +8,8 @@ const DS = require('interface-datastore')
 const CMS = require('./cms')
 const errcode = require('err-code')
 const { Number } = require('ipfs-utils/src/globalthis')
+const uint8ArrayToString = require('uint8arrays/to-string')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 require('node-forge/lib/sha512')
 
@@ -155,7 +157,7 @@ class Keychain {
   static generateOptions () {
     const options = Object.assign({}, defaultOptions)
     const saltLength = Math.ceil(NIST.minSaltLength / 3) * 3 // no base64 padding
-    options.dek.salt = crypto.randomBytes(saltLength).toString('base64')
+    options.dek.salt = uint8ArrayToString(crypto.randomBytes(saltLength), 'base64')
     return options
   }
 
@@ -212,8 +214,8 @@ class Keychain {
         id: kid
       }
       const batch = self.store.batch()
-      batch.put(dsname, pem)
-      batch.put(DsInfoName(name), JSON.stringify(keyInfo))
+      batch.put(dsname, uint8ArrayFromString(pem))
+      batch.put(DsInfoName(name), uint8ArrayFromString(JSON.stringify(keyInfo)))
 
       await batch.commit()
     } catch (err) {
@@ -236,7 +238,7 @@ class Keychain {
 
     const info = []
     for await (const value of self.store.query(query)) {
-      info.push(JSON.parse(value.value))
+      info.push(JSON.parse(uint8ArrayToString(value.value)))
     }
 
     return info
@@ -271,7 +273,7 @@ class Keychain {
     const dsname = DsInfoName(name)
     try {
       const res = await this.store.get(dsname)
-      return JSON.parse(res.toString())
+      return JSON.parse(uint8ArrayToString(res))
     } catch (err) {
       return throwDelayed(errcode(new Error(`Key '${name}' does not exist. ${err.message}`), 'ERR_KEY_NOT_FOUND'))
     }
@@ -321,15 +323,14 @@ class Keychain {
     if (exists) return throwDelayed(errcode(new Error(`Key '${newName}' already exists`), 'ERR_KEY_ALREADY_EXISTS'))
 
     try {
-      let res = await this.store.get(oldDsname)
-      const pem = res.toString()
-      res = await self.store.get(oldInfoName)
+      const pem = await self.store.get(oldDsname)
+      const res = await self.store.get(oldInfoName)
 
-      const keyInfo = JSON.parse(res.toString())
+      const keyInfo = JSON.parse(uint8ArrayToString(res))
       keyInfo.name = newName
       const batch = self.store.batch()
       batch.put(newDsname, pem)
-      batch.put(newInfoName, JSON.stringify(keyInfo))
+      batch.put(newInfoName, uint8ArrayFromString(JSON.stringify(keyInfo)))
       batch.delete(oldDsname)
       batch.delete(oldInfoName)
       await batch.commit()
@@ -357,7 +358,7 @@ class Keychain {
     const dsname = DsName(name)
     try {
       const res = await this.store.get(dsname)
-      const pem = res.toString()
+      const pem = uint8ArrayToString(res)
       const privateKey = await crypto.keys.import(pem, this._())
       return privateKey.export(password)
     } catch (err) {
@@ -405,8 +406,8 @@ class Keychain {
       id: kid
     }
     const batch = self.store.batch()
-    batch.put(dsname, pem)
-    batch.put(DsInfoName(name), JSON.stringify(keyInfo))
+    batch.put(dsname, uint8ArrayFromString(pem))
+    batch.put(DsInfoName(name), uint8ArrayFromString(JSON.stringify(keyInfo)))
     await batch.commit()
 
     return keyInfo
@@ -434,8 +435,8 @@ class Keychain {
         id: kid
       }
       const batch = self.store.batch()
-      batch.put(dsname, pem)
-      batch.put(DsInfoName(name), JSON.stringify(keyInfo))
+      batch.put(dsname, uint8ArrayFromString(pem))
+      batch.put(DsInfoName(name), uint8ArrayFromString(JSON.stringify(keyInfo)))
       await batch.commit()
       return keyInfo
     } catch (err) {
@@ -458,7 +459,7 @@ class Keychain {
     try {
       const dsname = DsName(name)
       const res = await this.store.get(dsname)
-      return res.toString()
+      return uint8ArrayToString(res)
     } catch (err) {
       return throwDelayed(errcode(new Error(`Key '${name}' does not exist. ${err.message}`), 'ERR_KEY_NOT_FOUND'))
     }
diff --git a/src/keychain/util.js b/src/keychain/util.js
index 50ce4174..816b4366 100644
--- a/src/keychain/util.js
+++ b/src/keychain/util.js
@@ -8,13 +8,13 @@ exports = module.exports
 /**
  * Gets a self-signed X.509 certificate for the key.
  *
- * The output Buffer contains the PKCS #7 message in DER.
+ * The output Uint8Array contains the PKCS #7 message in DER.
  *
  * TODO: move to libp2p-crypto package
  *
  * @param {KeyInfo} key - The id and name of the key
  * @param {RsaPrivateKey} privateKey - The naked key
- * @returns {undefined}
+ * @returns {Uint8Array}
  */
 exports.certificateForKey = (key, privateKey) => {
   const publicKey = pki.setRsaPublicKey(privateKey.n, privateKey.e)
diff --git a/src/peer-store/README.md b/src/peer-store/README.md
index 9c715c99..b95cdaf0 100644
--- a/src/peer-store/README.md
+++ b/src/peer-store/README.md
@@ -75,9 +75,9 @@ A `peerId.toB58String()` identifier mapping to a `Set` of protocol identifier st
 
 #### Metadata Book
 
-The `metadataBook` keeps track of the known metadata of a peer. Its metadata is stored in a key value fashion, where a key identifier (`string`) represents a metadata value (`Buffer`).
+The `metadataBook` keeps track of the known metadata of a peer. Its metadata is stored in a key value fashion, where a key identifier (`string`) represents a metadata value (`Uint8Array`).
 
-`Map<string, Map<string, Buffer>>`
+`Map<string, Map<string, Uint8Array>>`
 
 A `peerId.toB58String()` identifier mapping to the peer metadata Map.
 
diff --git a/src/peer-store/address-book.js b/src/peer-store/address-book.js
index d4c958a8..0036a0ce 100644
--- a/src/peer-store/address-book.js
+++ b/src/peer-store/address-book.js
@@ -31,7 +31,7 @@ class AddressBook extends Book {
   /**
   * CertifiedRecord object
   * @typedef {Object} CertifiedRecord
-  * @property {Buffer} raw raw envelope.
+  * @property {Uint8Array} raw raw envelope.
   * @property {number} seqNumber seq counter.
   */
 
@@ -128,7 +128,7 @@ class AddressBook extends Book {
    * Get the raw Envelope for a peer. Returns
    * undefined if no Envelope is found.
    * @param {PeerId} peerId
-   * @return {Buffer|undefined}
+   * @return {Uint8Array|undefined}
    */
   getRawEnvelope (peerId) {
     const entry = this.data.get(peerId.toB58String())
diff --git a/src/peer-store/metadata-book.js b/src/peer-store/metadata-book.js
index 148ded41..bd84f53a 100644
--- a/src/peer-store/metadata-book.js
+++ b/src/peer-store/metadata-book.js
@@ -4,8 +4,7 @@ const errcode = require('err-code')
 const debug = require('debug')
 const log = debug('libp2p:peer-store:proto-book')
 log.error = debug('libp2p:peer-store:proto-book:error')
-
-const { Buffer } = require('buffer')
+const uint8ArrayEquals = require('uint8arrays/equals')
 
 const PeerId = require('peer-id')
 
@@ -38,7 +37,7 @@ class MetadataBook extends Book {
 
     /**
      * Map known peers to their known protocols.
-     * @type {Map<string, Map<string, Buffer>>}
+     * @type {Map<string, Map<string, Uint8Array>>}
      */
     this.data = new Map()
   }
@@ -48,7 +47,7 @@ class MetadataBook extends Book {
    * @override
    * @param {PeerId} peerId
    * @param {string} key metadata key
-   * @param {Buffer} value metadata value
+   * @param {Uint8Array} value metadata value
    * @returns {ProtoBook}
    */
   set (peerId, key, value) {
@@ -57,7 +56,7 @@ class MetadataBook extends Book {
       throw errcode(new Error('peerId must be an instance of peer-id'), ERR_INVALID_PARAMETERS)
     }
 
-    if (typeof key !== 'string' || !Buffer.isBuffer(value)) {
+    if (typeof key !== 'string' || !(value instanceof Uint8Array)) {
       log.error('valid key and value must be provided to store data')
       throw errcode(new Error('valid key and value must be provided'), ERR_INVALID_PARAMETERS)
     }
@@ -77,7 +76,7 @@ class MetadataBook extends Book {
     const recMap = rec.get(key)
 
     // Already exists and is equal
-    if (recMap && value.equals(recMap)) {
+    if (recMap && uint8ArrayEquals(value, recMap)) {
       log(`the metadata provided to store is equal to the already stored for ${id} on ${key}`)
       return
     }
@@ -91,7 +90,7 @@ class MetadataBook extends Book {
   /**
    * Get the known data of a provided peer.
    * @param {PeerId} peerId
-   * @returns {Map<string, Buffer>}
+   * @returns {Map<string, Uint8Array>}
    */
   get (peerId) {
     if (!PeerId.isPeerId(peerId)) {
@@ -105,7 +104,7 @@ class MetadataBook extends Book {
    * Get specific metadata value, if it exists
    * @param {PeerId} peerId
    * @param {string} key
-   * @returns {Buffer}
+   * @returns {Uint8Array}
    */
   getValue (peerId, key) {
     if (!PeerId.isPeerId(peerId)) {
diff --git a/src/peer-store/persistent/index.js b/src/peer-store/persistent/index.js
index 7860f7e7..68505911 100644
--- a/src/peer-store/persistent/index.js
+++ b/src/peer-store/persistent/index.js
@@ -189,7 +189,7 @@ class PersistentPeerStore extends PeerStore {
 
       const encodedData = Addresses.encode({
         addrs: entry.addresses.map((address) => ({
-          multiaddr: address.multiaddr.buffer,
+          multiaddr: address.multiaddr.bytes,
           isCertified: address.isCertified
         })),
         certified_record: entry.record ? {
@@ -287,7 +287,7 @@ class PersistentPeerStore extends PeerStore {
    * @private
    * @param {Object} params
    * @param {Key} params.key datastore key
-   * @param {Buffer} params.value datastore value stored
+   * @param {Uint8Array} params.value datastore value stored
    * @return {Promise<void>}
    */
   async _processDatastoreEntry ({ key, value }) {
diff --git a/src/pnet/README.md b/src/pnet/README.md
index 97d5c0b5..d3cce111 100644
--- a/src/pnet/README.md
+++ b/src/pnet/README.md
@@ -64,7 +64,7 @@ node -e "require('libp2p/src/pnet').generate(process.stdout)" > swarm.key
 
 ```js
 const writeKey = require('libp2p/src/pnet').generate
-const swarmKey = Buffer.alloc(95)
+const swarmKey = new Uint8Array(95)
 writeKey(swarmKey)
 fs.writeFileSync('swarm.key', swarmKey)
 ```
diff --git a/src/pnet/crypto.js b/src/pnet/crypto.js
index 1675b372..ec8f4452 100644
--- a/src/pnet/crypto.js
+++ b/src/pnet/crypto.js
@@ -1,10 +1,11 @@
 'use strict'
 
-const { Buffer } = require('buffer')
 const debug = require('debug')
 const Errors = require('./errors')
 const xsalsa20 = require('xsalsa20')
 const KEY_LENGTH = require('./key-generator').KEY_LENGTH
+const uint8ArrayFromString = require('uint8arrays/from-string')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 const log = debug('libp2p:pnet')
 log.trace = debug('libp2p:pnet:trace')
@@ -13,15 +14,15 @@ log.error = debug('libp2p:pnet:err')
 /**
   * Creates a stream iterable to encrypt messages in a private network
  *
- * @param {Buffer} nonce The nonce to use in encryption
- * @param {Buffer} psk The private shared key to use in encryption
+ * @param {Uint8Array} nonce The nonce to use in encryption
+ * @param {Uint8Array} psk The private shared key to use in encryption
  * @returns {*} a through iterable
  */
 module.exports.createBoxStream = (nonce, psk) => {
   const xor = xsalsa20(nonce, psk)
   return (source) => (async function * () {
     for await (const chunk of source) {
-      yield Buffer.from(xor.update(chunk.slice()))
+      yield Uint8Array.from(xor.update(chunk.slice()))
     }
   })()
 }
@@ -29,8 +30,8 @@ module.exports.createBoxStream = (nonce, psk) => {
 /**
   * Creates a stream iterable to decrypt messages in a private network
  *
- * @param {Buffer} nonce The nonce of the remote peer
- * @param {Buffer} psk The private shared key to use in decryption
+ * @param {Uint8Array} nonce The nonce of the remote peer
+ * @param {Uint8Array} psk The private shared key to use in decryption
  * @returns {*} a through iterable
  */
 module.exports.createUnboxStream = (nonce, psk) => {
@@ -39,15 +40,15 @@ module.exports.createUnboxStream = (nonce, psk) => {
     log.trace('Decryption enabled')
 
     for await (const chunk of source) {
-      yield Buffer.from(xor.update(chunk.slice()))
+      yield Uint8Array.from(xor.update(chunk.slice()))
     }
   })()
 }
 
 /**
- * Decode the version 1 psk from the given Buffer
+ * Decode the version 1 psk from the given Uint8Array
  *
- * @param {Buffer} pskBuffer
+ * @param {Uint8Array} pskBuffer
  * @throws {INVALID_PSK}
  * @returns {Object} The PSK metadata (tag, codecName, psk)
  */
@@ -58,10 +59,10 @@ module.exports.decodeV1PSK = (pskBuffer) => {
     // from the buffer line by line to evaluate the next line
     // programmatically instead of making assumptions about the
     // encodings of each line.
-    const metadata = pskBuffer.toString().split(/(?:\r\n|\r|\n)/g)
+    const metadata = uint8ArrayToString(pskBuffer).split(/(?:\r\n|\r|\n)/g)
     const pskTag = metadata.shift()
     const codec = metadata.shift()
-    const psk = Buffer.from(metadata.shift(), 'hex')
+    const psk = uint8ArrayFromString(metadata.shift(), 'base16')
 
     if (psk.byteLength !== KEY_LENGTH) {
       throw new Error(Errors.INVALID_PSK)
diff --git a/src/pnet/index.js b/src/pnet/index.js
index 2754e6de..43b5a527 100644
--- a/src/pnet/index.js
+++ b/src/pnet/index.js
@@ -25,7 +25,7 @@ log.error = debug('libp2p:pnet:err')
  */
 class Protector {
   /**
-   * @param {Buffer} keyBuffer The private shared key buffer
+   * @param {Uint8Array} keyBuffer The private shared key buffer
    * @constructor
    */
   constructor (keyBuffer) {
diff --git a/src/pnet/key-generator.js b/src/pnet/key-generator.js
index 53840d13..64a24dfb 100644
--- a/src/pnet/key-generator.js
+++ b/src/pnet/key-generator.js
@@ -2,15 +2,19 @@
 
 const crypto = require('libp2p-crypto')
 const KEY_LENGTH = 32
+const uint8ArrayToString = require('uint8arrays/to-string')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 /**
  * Generates a PSK that can be used in a libp2p-pnet private network
- * @param {Writer} writer An object containing a `write` method
+ * @param {Uint8Array} bytes An object to write the psk into
  * @returns {void}
  */
-function generate (writer) {
-  const psk = crypto.randomBytes(KEY_LENGTH).toString('hex')
-  writer.write('/key/swarm/psk/1.0.0/\n/base16/\n' + psk)
+function generate (bytes) {
+  const psk = uint8ArrayToString(crypto.randomBytes(KEY_LENGTH), 'base16')
+  const key = uint8ArrayFromString('/key/swarm/psk/1.0.0/\n/base16/\n' + psk)
+
+  bytes.set(key)
 }
 
 module.exports = generate
diff --git a/src/pubsub.js b/src/pubsub.js
index df8667c7..f602408d 100644
--- a/src/pubsub.js
+++ b/src/pubsub.js
@@ -1,8 +1,8 @@
 'use strict'
 
-const { Buffer } = require('buffer')
 const errCode = require('err-code')
 const { messages, codes } = require('./errors')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 module.exports = (node, Pubsub, config) => {
   const pubsub = new Pubsub(node.peerId, node.registrar, config)
@@ -50,7 +50,7 @@ module.exports = (node, Pubsub, config) => {
     /**
      * Publish messages to the given topics.
      * @param {Array<string>|string} topic
-     * @param {Buffer} data
+     * @param {Uint8Array} data
      * @returns {Promise<void>}
      */
     publish: (topic, data) => {
@@ -58,10 +58,14 @@ module.exports = (node, Pubsub, config) => {
         throw errCode(new Error(messages.NOT_STARTED_YET), codes.PUBSUB_NOT_STARTED)
       }
 
+      if (typeof data === 'string' || data instanceof String) {
+        data = uint8ArrayFromString(data)
+      }
+
       try {
-        data = Buffer.from(data)
+        data = Uint8Array.from(data)
       } catch (err) {
-        throw errCode(new Error('data must be convertible to a Buffer'), 'ERR_DATA_IS_NOT_VALID')
+        throw errCode(new Error('data must be convertible to a Uint8Array'), 'ERR_DATA_IS_NOT_VALID')
       }
 
       return pubsub.publish(topic, data)
diff --git a/src/record/README.md b/src/record/README.md
index 0a665fa5..47a5600b 100644
--- a/src/record/README.md
+++ b/src/record/README.md
@@ -17,10 +17,11 @@ You can read further about the envelope in [libp2p/specs#217](https://github.com
 ```js
 // interface-record implementation example with the "libp2p-example" namespace
 const Record = require('libp2p-interfaces/src/record')
+const fromString = require('uint8arrays/from-string')
 
 class ExampleRecord extends Record {
   constructor () {
-    super ('libp2p-example', Buffer.from('0302', 'hex'))
+    super ('libp2p-example', fromString('0302', 'hex'))
   }
 
   marshal () {}
diff --git a/src/record/envelope/index.js b/src/record/envelope/index.js
index 72f77900..528c6745 100644
--- a/src/record/envelope/index.js
+++ b/src/record/envelope/index.js
@@ -4,12 +4,12 @@ const debug = require('debug')
 const log = debug('libp2p:envelope')
 log.error = debug('libp2p:envelope:error')
 const errCode = require('err-code')
-
-const { Buffer } = require('buffer')
-
-const crypto = require('libp2p-crypto')
+const uint8arraysConcat = require('uint8arrays/concat')
+const uint8arraysFromString = require('uint8arrays/from-string')
+const cryptoKeys = require('libp2p-crypto/src/keys')
 const PeerId = require('peer-id')
 const varint = require('varint')
+const uint8arraysEquals = require('uint8arrays/equals')
 
 const { codes } = require('../../errors')
 const Protobuf = require('./envelope.proto')
@@ -23,9 +23,9 @@ class Envelope {
    * @constructor
    * @param {object} params
    * @param {PeerId} params.peerId
-   * @param {Buffer} params.payloadType
-   * @param {Buffer} params.payload marshaled record
-   * @param {Buffer} params.signature signature of the domain string :: type hint :: payload.
+   * @param {Uint8Array} params.payloadType
+   * @param {Uint8Array} params.payload marshaled record
+   * @param {Uint8Array} params.signature signature of the domain string :: type hint :: payload.
    */
   constructor ({ peerId, payloadType, payload, signature }) {
     this.peerId = peerId
@@ -39,14 +39,14 @@ class Envelope {
 
   /**
    * Marshal the envelope content.
-   * @return {Buffer}
+   * @return {Uint8Array}
    */
   marshal () {
     if (this._marshal) {
       return this._marshal
     }
 
-    const publicKey = crypto.keys.marshalPublicKey(this.peerId.pubKey)
+    const publicKey = cryptoKeys.marshalPublicKey(this.peerId.pubKey)
 
     this._marshal = Protobuf.encode({
       public_key: publicKey,
@@ -64,10 +64,10 @@ class Envelope {
    * @return {boolean}
    */
   equals (other) {
-    return this.peerId.pubKey.bytes.equals(other.peerId.pubKey.bytes) &&
-      this.payloadType.equals(other.payloadType) &&
-      this.payload.equals(other.payload) &&
-      this.signature.equals(other.signature)
+    return uint8arraysEquals(this.peerId.pubKey.bytes, other.peerId.pubKey.bytes) &&
+      uint8arraysEquals(this.payloadType, other.payloadType) &&
+      uint8arraysEquals(this.payload, other.payload) &&
+      uint8arraysEquals(this.signature, other.signature)
   }
 
   /**
@@ -83,14 +83,14 @@ class Envelope {
 }
 
 /**
- * Helper function that prepares a buffer to sign or verify a signature.
+ * Helper function that prepares a Uint8Array to sign or verify a signature.
  * @param {string} domain
- * @param {Buffer} payloadType
- * @param {Buffer} payload
- * @return {Buffer}
+ * @param {Uint8Array} payloadType
+ * @param {Uint8Array} payload
+ * @return {Uint8Array}
  */
 const formatSignaturePayload = (domain, payloadType, payload) => {
-  // When signing, a peer will prepare a buffer by concatenating the following:
+  // When signing, a peer will prepare a Uint8Array by concatenating the following:
   // - The length of the domain separation string string in bytes
   // - The domain separation string, encoded as UTF-8
   // - The length of the payload_type field in bytes
@@ -98,23 +98,24 @@ const formatSignaturePayload = (domain, payloadType, payload) => {
   // - The length of the payload field in bytes
   // - The value of the payload field
 
-  const domainLength = varint.encode(Buffer.byteLength(domain))
+  domain = uint8arraysFromString(domain)
+  const domainLength = varint.encode(domain.byteLength)
   const payloadTypeLength = varint.encode(payloadType.length)
   const payloadLength = varint.encode(payload.length)
 
-  return Buffer.concat([
-    Buffer.from(domainLength),
-    Buffer.from(domain),
-    Buffer.from(payloadTypeLength),
+  return uint8arraysConcat([
+    new Uint8Array(domainLength),
+    domain,
+    new Uint8Array(payloadTypeLength),
     payloadType,
-    Buffer.from(payloadLength),
+    new Uint8Array(payloadLength),
     payload
   ])
 }
 
 /**
  * Unmarshal a serialized Envelope protobuf message.
- * @param {Buffer} data
+ * @param {Uint8Array} data
  * @return {Promise<Envelope>}
  */
 Envelope.createFromProtobuf = async (data) => {
@@ -139,7 +140,7 @@ Envelope.createFromProtobuf = async (data) => {
 */
 Envelope.seal = async (record, peerId) => {
   const domain = record.domain
-  const payloadType = Buffer.from(record.codec)
+  const payloadType = uint8arraysFromString(record.codec)
   const payload = record.marshal()
 
   const signData = formatSignaturePayload(domain, payloadType, payload)
@@ -156,7 +157,7 @@ Envelope.seal = async (record, peerId) => {
 /**
  * Open and certify a given marshalled envelope.
  * Data is unmarshalled and the signature validated for the given domain.
- * @param {Buffer} data
+ * @param {Uint8Array} data
  * @param {string} domain
  * @return {Envelope}
  */
diff --git a/src/record/peer-record/index.js b/src/record/peer-record/index.js
index 432f9501..2bd5cdc9 100644
--- a/src/record/peer-record/index.js
+++ b/src/record/peer-record/index.js
@@ -36,7 +36,7 @@ class PeerRecord extends Record {
 
   /**
    * Marshal a record to be used in an envelope.
-   * @return {Buffer}
+   * @return {Uint8Array}
    */
   marshal () {
     if (this._marshal) {
@@ -47,7 +47,7 @@ class PeerRecord extends Record {
       peer_id: this.peerId.toBytes(),
       seq: this.seqNumber,
       addresses: this.multiaddrs.map((m) => ({
-        multiaddr: m.buffer
+        multiaddr: m.bytes
       }))
     })
 
@@ -81,7 +81,7 @@ class PeerRecord extends Record {
 
 /**
  * Unmarshal Peer Record Protobuf.
- * @param {Buffer} buf marshaled peer record.
+ * @param {Uint8Array} buf marshaled peer record.
  * @return {PeerRecord}
  */
 PeerRecord.createFromProtobuf = (buf) => {
diff --git a/test/content-routing/content-routing.node.js b/test/content-routing/content-routing.node.js
index 1fc7967d..adda6c13 100644
--- a/test/content-routing/content-routing.node.js
+++ b/test/content-routing/content-routing.node.js
@@ -3,6 +3,7 @@
 
 const chai = require('chai')
 chai.use(require('dirty-chai'))
+chai.use(require('chai-as-promised'))
 const { expect } = chai
 const nock = require('nock')
 const sinon = require('sinon')
@@ -96,7 +97,7 @@ describe('content-routing', () => {
     let delegate
 
     beforeEach(async () => {
-      const [peerId] = await peerUtils.createPeerId({ fixture: false })
+      const [peerId] = await peerUtils.createPeerId({ fixture: true })
 
       delegate = new DelegatedContentRouter(peerId, {
         host: '0.0.0.0',
@@ -227,7 +228,7 @@ describe('content-routing', () => {
     let delegate
 
     beforeEach(async () => {
-      const [peerId] = await peerUtils.createPeerId({ fixture: false })
+      const [peerId] = await peerUtils.createPeerId({ fixture: true })
 
       delegate = new DelegatedContentRouter(peerId, {
         host: '0.0.0.0',
diff --git a/test/content-routing/dht/operation.node.js b/test/content-routing/dht/operation.node.js
index b9dc7118..6f8a4a0b 100644
--- a/test/content-routing/dht/operation.node.js
+++ b/test/content-routing/dht/operation.node.js
@@ -1,14 +1,12 @@
 'use strict'
 /* eslint-env mocha */
 
-const { Buffer } = require('buffer')
-const chai = require('chai')
-chai.use(require('dirty-chai'))
-const { expect } = chai
+const { expect } = require('aegir/utils/chai')
 
 const multiaddr = require('multiaddr')
 const pWaitFor = require('p-wait-for')
 const mergeOptions = require('merge-options')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const { create } = require('../../../src')
 const { subsystemOptions, subsystemMulticodecs } = require('./utils')
@@ -68,8 +66,8 @@ describe('DHT subsystem operates correctly', () => {
     })
 
     it('should put on a peer and get from the other', async () => {
-      const key = Buffer.from('hello')
-      const value = Buffer.from('world')
+      const key = uint8ArrayFromString('hello')
+      const value = uint8ArrayFromString('world')
 
       await libp2p.dialProtocol(remAddr, subsystemMulticodecs)
       await Promise.all([
@@ -131,8 +129,8 @@ describe('DHT subsystem operates correctly', () => {
     it('should put on a peer and get from the other', async () => {
       await libp2p.dial(remAddr)
 
-      const key = Buffer.from('hello')
-      const value = Buffer.from('world')
+      const key = uint8ArrayFromString('hello')
+      const value = uint8ArrayFromString('world')
 
       await remoteLibp2p._dht.start()
       await pWaitFor(() => libp2p._dht.routingTable.size === 1)
diff --git a/test/dialing/direct.node.js b/test/dialing/direct.node.js
index 98614a45..401f4eb5 100644
--- a/test/dialing/direct.node.js
+++ b/test/dialing/direct.node.js
@@ -1,11 +1,7 @@
 'use strict'
 /* eslint-env mocha */
 
-const { Buffer } = require('buffer')
-const chai = require('chai')
-chai.use(require('dirty-chai'))
-chai.use(require('chai-as-promised'))
-const { expect } = chai
+const { expect } = require('aegir/utils/chai')
 const sinon = require('sinon')
 const Transport = require('libp2p-tcp')
 const Muxer = require('libp2p-mplex')
@@ -19,6 +15,7 @@ const pipe = require('it-pipe')
 const AggregateError = require('aggregate-error')
 const { Connection } = require('libp2p-interfaces/src/connection')
 const { AbortError } = require('libp2p-interfaces/src/transport/errors')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const Libp2p = require('../../src')
 const Dialer = require('../../src/dialer')
@@ -27,7 +24,7 @@ const PeerStore = require('../../src/peer-store')
 const TransportManager = require('../../src/transport-manager')
 const { codes: ErrorCodes } = require('../../src/errors')
 const Protector = require('../../src/pnet')
-const swarmKeyBuffer = Buffer.from(require('../fixtures/swarm.key'))
+const swarmKeyBuffer = uint8ArrayFromString(require('../fixtures/swarm.key'))
 
 const mockUpgrader = require('../utils/mockUpgrader')
 const createMockConnection = require('../utils/mockConnection')
diff --git a/test/dialing/relay.node.js b/test/dialing/relay.node.js
index 79f8ac37..a5919408 100644
--- a/test/dialing/relay.node.js
+++ b/test/dialing/relay.node.js
@@ -1,7 +1,6 @@
 'use strict'
 /* eslint-env mocha */
 
-const { Buffer } = require('buffer')
 const chai = require('chai')
 chai.use(require('dirty-chai'))
 chai.use(require('chai-as-promised'))
@@ -13,6 +12,7 @@ const { collect } = require('streaming-iterables')
 const pipe = require('it-pipe')
 const AggregateError = require('aggregate-error')
 const PeerId = require('peer-id')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const { createPeerId } = require('../utils/creators/peer')
 const baseOptions = require('../utils/base-options')
@@ -88,7 +88,7 @@ describe('Dialing (via relay, TCP)', () => {
     )
 
     const { stream: echoStream } = await connection.newStream('/echo/1.0.0')
-    const input = Buffer.from('hello')
+    const input = uint8ArrayFromString('hello')
     const [output] = await pipe(
       [input],
       echoStream,
@@ -162,7 +162,7 @@ describe('Dialing (via relay, TCP)', () => {
 
     // Tamper with the our multiaddrs for the circuit message
     sinon.stub(srcLibp2p, 'multiaddrs').value([{
-      buffer: Buffer.from('an invalid multiaddr')
+      bytes: uint8ArrayFromString('an invalid multiaddr')
     }])
 
     await expect(srcLibp2p.dial(dialAddr))
diff --git a/test/identify/index.spec.js b/test/identify/index.spec.js
index 2e83ff65..799a3ebd 100644
--- a/test/identify/index.spec.js
+++ b/test/identify/index.spec.js
@@ -13,6 +13,7 @@ const PeerId = require('peer-id')
 const duplexPair = require('it-pair/duplex')
 const multiaddr = require('multiaddr')
 const pWaitFor = require('p-wait-for')
+const unit8ArrayToString = require('uint8arrays/to-string')
 
 const { codes: Errors } = require('../../src/errors')
 const { IdentifyService, multicodecs } = require('../../src/identify')
@@ -148,7 +149,7 @@ describe('Identify', () => {
     const metadataArgs = localIdentify.peerStore.metadataBook.set.firstCall.args
     expect(metadataArgs[0].id.bytes).to.equal(remotePeer.bytes)
     expect(metadataArgs[1]).to.equal('AgentVersion')
-    expect(metadataArgs[2].toString()).to.equal(`js-libp2p/${pkg.version}`)
+    expect(unit8ArrayToString(metadataArgs[2])).to.equal(`js-libp2p/${pkg.version}`)
 
     // Validate the remote peer gets updated in the peer store
     const call = localIdentify.peerStore.addressBook.set.firstCall
diff --git a/test/insecure/plaintext.spec.js b/test/insecure/plaintext.spec.js
index 3642e8f1..b0c0e9cb 100644
--- a/test/insecure/plaintext.spec.js
+++ b/test/insecure/plaintext.spec.js
@@ -1,7 +1,6 @@
 'use strict'
 /* eslint-env mocha */
 
-const { Buffer } = require('buffer')
 const chai = require('chai')
 chai.use(require('dirty-chai'))
 const { expect } = chai
@@ -56,7 +55,7 @@ describe('plaintext', () => {
 
     // When we attempt to get the remote peer key, return the wrong peers pub key
     sinon.stub(remotePeer, 'marshalPubKey').callsFake(() => {
-      return Buffer.alloc(0)
+      return new Uint8Array(0)
     })
 
     return Promise.all([
diff --git a/test/keychain/cms-interop.spec.js b/test/keychain/cms-interop.spec.js
index 8eb19f6e..1c39eda5 100644
--- a/test/keychain/cms-interop.spec.js
+++ b/test/keychain/cms-interop.spec.js
@@ -7,13 +7,9 @@ const dirtyChai = require('dirty-chai')
 const expect = chai.expect
 chai.use(dirtyChai)
 chai.use(require('chai-string'))
-
-const os = require('os')
-const path = require('path')
-const { isNode } = require('ipfs-utils/src/env')
-const FsStore = require('datastore-fs')
-const LevelStore = require('datastore-level')
-
+const uint8ArrayFromString = require('uint8arrays/from-string')
+const uint8ArrayToString = require('uint8arrays/to-string')
+const { MemoryDatastore } = require('interface-datastore')
 const Keychain = require('../../src/keychain')
 
 describe('cms interop', () => {
@@ -22,13 +18,11 @@ describe('cms interop', () => {
   let ks
 
   before(() => {
-    const datastore = isNode
-      ? new FsStore(path.join(os.tmpdir(), 'test-keystore-1-' + Date.now()))
-      : new LevelStore('test-keystore-1', { db: require('level') })
+    const datastore = new MemoryDatastore()
     ks = new Keychain(datastore, { passPhrase: passPhrase })
   })
 
-  const plainData = Buffer.from('This is a message from Alice to Bob')
+  const plainData = uint8ArrayFromString('This is a message from Alice to Bob')
 
   it('imports openssl key', async function () {
     this.timeout(10 * 1000)
@@ -67,8 +61,8 @@ knU1yykWGkdlbclCuu0NaAfmb8o0OX50CbEKZB7xmsv8tnqn0H0jMF4GCSqGSIb3
 DQEHATAdBglghkgBZQMEASoEEP/PW1JWehQx6/dsLkp/Mf+gMgQwFM9liLTqC56B
 nHILFmhac/+a/StQOKuf9dx5qXeGvt9LnwKuGGSfNX4g+dTkoa6N
 `
-    const plain = await ks.cms.decrypt(Buffer.from(example, 'base64'))
+    const plain = await ks.cms.decrypt(uint8ArrayFromString(example.replace(/\s/g, ''), 'base64'))
     expect(plain).to.exist()
-    expect(plain.toString()).to.equal(plainData.toString())
+    expect(uint8ArrayToString(plain)).to.equal(uint8ArrayToString(plainData))
   })
 })
diff --git a/test/keychain/keychain.spec.js b/test/keychain/keychain.spec.js
index 0451cd37..8124c72c 100644
--- a/test/keychain/keychain.spec.js
+++ b/test/keychain/keychain.spec.js
@@ -5,15 +5,12 @@
 const { chai, expect } = require('aegir/utils/chai')
 const fail = expect.fail
 chai.use(require('chai-string'))
+const uint8ArrayFromString = require('uint8arrays/from-string')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 const peerUtils = require('../utils/creators/peer')
 
-const os = require('os')
-const path = require('path')
-const { isNode } = require('ipfs-utils/src/env')
 const { MemoryDatastore } = require('interface-datastore')
-const FsStore = require('datastore-fs')
-const LevelStore = require('datastore-level')
 const Keychain = require('../../src/keychain')
 const PeerId = require('peer-id')
 
@@ -26,16 +23,20 @@ describe('keychain', () => {
   let ks
   let datastore1, datastore2
 
-  before(() => {
-    datastore1 = isNode
-      ? new FsStore(path.join(os.tmpdir(), 'test-keystore-1-' + Date.now()))
-      : new LevelStore('test-keystore-1', { db: require('level') })
-    datastore2 = isNode
-      ? new FsStore(path.join(os.tmpdir(), 'test-keystore-2-' + Date.now()))
-      : new LevelStore('test-keystore-2', { db: require('level') })
+  before(async () => {
+    datastore1 = new MemoryDatastore()
+    datastore2 = new MemoryDatastore()
 
     ks = new Keychain(datastore2, { passPhrase: passPhrase })
     emptyKeystore = new Keychain(datastore1, { passPhrase: passPhrase })
+
+    await datastore1.open()
+    await datastore2.open()
+  })
+
+  after(async () => {
+    await datastore2.close()
+    await datastore2.close()
   })
 
   it('can start without a password', () => {
@@ -74,7 +75,7 @@ describe('keychain', () => {
     const keychainWithPassword = new Keychain(datastore2, { passPhrase: `hello-${Date.now()}-${Date.now()}` })
     const id = `key-${Math.random()}`
 
-    await keychainWithPassword.createKey(id, 'rsa', 2048)
+    await keychainWithPassword.createKey(id, 'ed25519')
 
     await expect(keychain.findKeyById(id)).to.eventually.be.ok()
   })
@@ -84,7 +85,7 @@ describe('keychain', () => {
     const keychainWithPassword = new Keychain(datastore2, { passPhrase: `hello-${Date.now()}-${Date.now()}` })
     const name = `key-${Math.random()}`
 
-    expect(await keychainWithPassword.createKey(name, 'rsa', 2048)).to.have.property('name', name)
+    expect(await keychainWithPassword.createKey(name, 'ed25519')).to.have.property('name', name)
     expect(await keychainWithoutPassword.findKeyByName(name)).to.have.property('name', name)
     await keychainWithoutPassword.removeKey(name)
     await expect(keychainWithoutPassword.findKeyByName(name)).to.be.rejectedWith(/does not exist/)
@@ -278,7 +279,7 @@ describe('keychain', () => {
   })
 
   describe('CMS protected data', () => {
-    const plainData = Buffer.from('This is a message from Alice to Bob')
+    const plainData = uint8ArrayFromString('This is a message from Alice to Bob')
     let cms
 
     it('service is available', () => {
@@ -291,7 +292,7 @@ describe('keychain', () => {
       expect(err).to.have.property('code', 'ERR_KEY_NOT_FOUND')
     })
 
-    it('requires plain data as a Buffer', async () => {
+    it('requires plain data as a Uint8Array', async () => {
       const err = await ks.cms.encrypt(rsaKeyName, 'plain data').then(fail, err => err)
       expect(err).to.exist()
       expect(err).to.have.property('code', 'ERR_INVALID_PARAMS')
@@ -300,7 +301,7 @@ describe('keychain', () => {
     it('encrypts', async () => {
       cms = await ks.cms.encrypt(rsaKeyName, plainData)
       expect(cms).to.exist()
-      expect(cms).to.be.instanceOf(Buffer)
+      expect(cms).to.be.instanceOf(Uint8Array)
     })
 
     it('is a PKCS #7 message', async () => {
@@ -326,7 +327,7 @@ describe('keychain', () => {
     it('can be read with the key', async () => {
       const plain = await ks.cms.decrypt(cms)
       expect(plain).to.exist()
-      expect(plain.toString()).to.equal(plainData.toString())
+      expect(uint8ArrayToString(plain)).to.equal(uint8ArrayToString(plainData))
     })
   })
 
@@ -380,7 +381,7 @@ describe('keychain', () => {
     let alice
 
     before(async function () {
-      const encoded = Buffer.from(alicePrivKey, 'base64')
+      const encoded = uint8ArrayFromString(alicePrivKey, 'base64pad')
       alice = await PeerId.createFromPrivKey(encoded)
     })
 
@@ -522,7 +523,7 @@ describe('libp2p.keychain', () => {
 
     await libp2p.loadKeychain()
 
-    const kInfo = await libp2p.keychain.createKey('keyName', 'rsa', 2048)
+    const kInfo = await libp2p.keychain.createKey('keyName', 'ed25519')
     expect(kInfo).to.exist()
   })
 
@@ -555,7 +556,7 @@ describe('libp2p.keychain', () => {
     })
     await libp2p.loadKeychain()
 
-    const kInfo = await libp2p.keychain.createKey('keyName', 'rsa', 2048)
+    const kInfo = await libp2p.keychain.createKey('keyName', 'ed25519')
     expect(kInfo).to.exist()
 
     const [libp2p2] = await peerUtils.createPeer({
diff --git a/test/keychain/peerid.spec.js b/test/keychain/peerid.spec.js
index 4360e538..430d47a7 100644
--- a/test/keychain/peerid.spec.js
+++ b/test/keychain/peerid.spec.js
@@ -10,6 +10,7 @@ const multihash = require('multihashes')
 const crypto = require('libp2p-crypto')
 const rsaUtils = require('libp2p-crypto/src/keys/rsa-utils')
 const rsaClass = require('libp2p-crypto/src/keys/rsa-class')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const sample = {
   id: '122019318b6e5e0cf93a2314bf01269a2cc23cd3dcd452d742cdb9379d8646f6e4a9',
@@ -22,7 +23,7 @@ describe('peer ID', () => {
   let publicKeyDer // a buffer
 
   before(async () => {
-    const encoded = Buffer.from(sample.privKey, 'base64')
+    const encoded = uint8ArrayFromString(sample.privKey, 'base64pad')
     peer = await PeerId.createFromPrivKey(encoded)
   })
 
diff --git a/test/peer-discovery/index.node.js b/test/peer-discovery/index.node.js
index 4d28e23c..bbea8a0a 100644
--- a/test/peer-discovery/index.node.js
+++ b/test/peer-discovery/index.node.js
@@ -13,6 +13,7 @@ const crypto = require('libp2p-crypto')
 const KadDht = require('libp2p-kad-dht')
 const MulticastDNS = require('libp2p-mdns')
 const multiaddr = require('multiaddr')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 const Libp2p = require('../../src')
 const baseOptions = require('../utils/base-options')
@@ -110,7 +111,7 @@ describe('peer discovery scenarios', () => {
             enabled: true,
             interval: 200, // discover quickly
             // use a random tag to prevent CI collision
-            serviceTag: crypto.randomBytes(10).toString('hex')
+            serviceTag: uint8ArrayToString(crypto.randomBytes(10), 'base16')
           }
         }
       }
diff --git a/test/peer-store/metadata-book.spec.js b/test/peer-store/metadata-book.spec.js
index 39bf5bed..8d3e815b 100644
--- a/test/peer-store/metadata-book.spec.js
+++ b/test/peer-store/metadata-book.spec.js
@@ -5,6 +5,7 @@ const chai = require('chai')
 chai.use(require('dirty-chai'))
 chai.use(require('chai-bytes'))
 const { expect } = chai
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const pDefer = require('p-defer')
 const PeerStore = require('../../src/peer-store')
@@ -76,7 +77,7 @@ describe('metadataBook', () => {
     it('stores the content and emit change event', () => {
       const defer = pDefer()
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       peerStore.once('change:metadata', ({ peerId, metadata }) => {
         expect(peerId).to.exist()
@@ -99,8 +100,8 @@ describe('metadataBook', () => {
     it('emits on set if not storing the exact same content', () => {
       const defer = pDefer()
       const metadataKey = 'location'
-      const metadataValue1 = Buffer.from('mars')
-      const metadataValue2 = Buffer.from('saturn')
+      const metadataValue1 = uint8ArrayFromString('mars')
+      const metadataValue2 = uint8ArrayFromString('saturn')
 
       let changeCounter = 0
       peerStore.on('change:metadata', () => {
@@ -129,7 +130,7 @@ describe('metadataBook', () => {
     it('does not emit on set if it is storing the exact same content', () => {
       const defer = pDefer()
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       let changeCounter = 0
       peerStore.on('change:metadata', () => {
@@ -180,7 +181,7 @@ describe('metadataBook', () => {
 
     it('returns the metadata stored', () => {
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
@@ -217,7 +218,7 @@ describe('metadataBook', () => {
 
     it('returns the metadata value stored for the given key', () => {
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
@@ -229,7 +230,7 @@ describe('metadataBook', () => {
     it('returns undefined if no metadata is known for the provided peer and key', () => {
       const metadataKey = 'location'
       const metadataBadKey = 'nickname'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
@@ -279,7 +280,7 @@ describe('metadataBook', () => {
     it('returns true if the record exists and an event is emitted', () => {
       const defer = pDefer()
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
@@ -337,7 +338,7 @@ describe('metadataBook', () => {
     it('returns true if the record exists and an event is emitted', () => {
       const defer = pDefer()
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
@@ -357,7 +358,7 @@ describe('metadataBook', () => {
       const defer = pDefer()
       const metadataKey = 'location'
       const metadataBadKey = 'nickname'
-      const metadataValue = Buffer.from('mars')
+      const metadataValue = uint8ArrayFromString('mars')
 
       mb.set(peerId, metadataKey, metadataValue)
 
diff --git a/test/peer-store/peer-store.spec.js b/test/peer-store/peer-store.spec.js
index 42af502b..c9d18800 100644
--- a/test/peer-store/peer-store.spec.js
+++ b/test/peer-store/peer-store.spec.js
@@ -7,6 +7,7 @@ const { expect } = chai
 
 const PeerStore = require('../../src/peer-store')
 const multiaddr = require('multiaddr')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const peerUtils = require('../utils/creators/peer')
 
@@ -196,7 +197,7 @@ describe('peer-store', () => {
 
     it('returns peers if only metadata is known', () => {
       const metadataKey = 'location'
-      const metadataValue = Buffer.from('earth')
+      const metadataValue = uint8ArrayFromString('earth')
       peerStore.metadataBook.set(peerIds[0], metadataKey, metadataValue)
 
       const peers = peerStore.peers
diff --git a/test/peer-store/persisted-peer-store.spec.js b/test/peer-store/persisted-peer-store.spec.js
index 0e201316..ee6b1ced 100644
--- a/test/peer-store/persisted-peer-store.spec.js
+++ b/test/peer-store/persisted-peer-store.spec.js
@@ -12,6 +12,7 @@ const PeerStore = require('../../src/peer-store/persistent')
 
 const multiaddr = require('multiaddr')
 const { MemoryDatastore } = require('interface-datastore')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const peerUtils = require('../utils/creators/peer')
 
@@ -145,7 +146,7 @@ describe('Persisted PeerStore', () => {
       await Promise.all(commitSpy.returnValues)
 
       // MetadataBook
-      peerStore.metadataBook.set(peers[0], 'location', Buffer.from('earth'))
+      peerStore.metadataBook.set(peers[0], 'location', uint8ArrayFromString('earth'))
 
       // let batch commit complete
       await Promise.all(commitSpy.returnValues)
@@ -186,7 +187,7 @@ describe('Persisted PeerStore', () => {
       // ProtoBook
       peerStore.protoBook.set(peer, protocols)
       // MetadataBook
-      peerStore.metadataBook.set(peer, 'location', Buffer.from('earth'))
+      peerStore.metadataBook.set(peer, 'location', uint8ArrayFromString('earth'))
 
       // let batch commit complete
       await Promise.all(commitSpy.returnValues)
@@ -408,7 +409,7 @@ describe('Persisted PeerStore', () => {
       // Add Peer0 data in multiple books
       peerStore.addressBook.set(peers[0], multiaddrs)
       peerStore.protoBook.set(peers[0], protocols)
-      peerStore.metadataBook.set(peers[0], 'location', Buffer.from('earth'))
+      peerStore.metadataBook.set(peers[0], 'location', uint8ArrayFromString('earth'))
 
       // let batch commit complete
       await Promise.all(commitSpy.returnValues)
diff --git a/test/pnet/index.spec.js b/test/pnet/index.spec.js
index c137f23f..9fa2b9f2 100644
--- a/test/pnet/index.spec.js
+++ b/test/pnet/index.spec.js
@@ -1,7 +1,6 @@
 /* eslint-env mocha */
 'use strict'
 
-const { Buffer } = require('buffer')
 const chai = require('chai')
 const dirtyChai = require('dirty-chai')
 chai.use(dirtyChai)
@@ -9,13 +8,14 @@ const expect = chai.expect
 const duplexPair = require('it-pair/duplex')
 const pipe = require('it-pipe')
 const { collect } = require('streaming-iterables')
+const uint8ArrayFromString = require('uint8arrays/from-string')
 
 const Protector = require('../../src/pnet')
 const Errors = Protector.errors
 const generate = Protector.generate
 
-const swarmKeyBuffer = Buffer.alloc(95)
-const wrongSwarmKeyBuffer = Buffer.alloc(95)
+const swarmKeyBuffer = new Uint8Array(95)
+const wrongSwarmKeyBuffer = new Uint8Array(95)
 
 // Write new psk files to the buffers
 generate(swarmKeyBuffer)
@@ -39,7 +39,7 @@ describe('private network', () => {
     ])
 
     pipe(
-      [Buffer.from('hello world'), Buffer.from('doo dah')],
+      [uint8ArrayFromString('hello world'), uint8ArrayFromString('doo dah')],
       aToB
     )
 
@@ -53,7 +53,7 @@ describe('private network', () => {
       collect
     )
 
-    expect(output).to.eql([Buffer.from('hello world'), Buffer.from('doo dah')])
+    expect(output).to.eql([uint8ArrayFromString('hello world'), uint8ArrayFromString('doo dah')])
   })
 
   it('should not be able to share correct data with different keys', async () => {
@@ -67,7 +67,7 @@ describe('private network', () => {
     ])
 
     pipe(
-      [Buffer.from('hello world'), Buffer.from('doo dah')],
+      [uint8ArrayFromString('hello world'), uint8ArrayFromString('doo dah')],
       aToB
     )
 
@@ -76,19 +76,19 @@ describe('private network', () => {
       collect
     )
 
-    expect(output).to.not.eql([Buffer.from('hello world'), Buffer.from('doo dah')])
+    expect(output).to.not.eql([uint8ArrayFromString('hello world'), uint8ArrayFromString('doo dah')])
   })
 
   describe('invalid psks', () => {
     it('should not accept a bad psk', () => {
       expect(() => {
-        return new Protector(Buffer.from('not-a-key'))
+        return new Protector(uint8ArrayFromString('not-a-key'))
       }).to.throw(Errors.INVALID_PSK)
     })
 
     it('should not accept a psk of incorrect length', () => {
       expect(() => {
-        return new Protector(Buffer.from('/key/swarm/psk/1.0.0/\n/base16/\ndffb7e'))
+        return new Protector(uint8ArrayFromString('/key/swarm/psk/1.0.0/\n/base16/\ndffb7e'))
       }).to.throw(Errors.INVALID_PSK)
     })
   })
diff --git a/test/pubsub/implementations.node.js b/test/pubsub/implementations.node.js
index 7ce32c0a..a17d7744 100644
--- a/test/pubsub/implementations.node.js
+++ b/test/pubsub/implementations.node.js
@@ -13,6 +13,7 @@ const Floodsub = require('libp2p-floodsub')
 const Gossipsub = require('libp2p-gossipsub')
 const { multicodec: floodsubMulticodec } = require('libp2p-floodsub')
 const { multicodec: gossipsubMulticodec } = require('libp2p-gossipsub')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 const multiaddr = require('multiaddr')
 
@@ -81,7 +82,7 @@ describe('Pubsub subsystem is able to use different implementations', () => {
     expect(connection).to.exist()
 
     libp2p.pubsub.subscribe(topic, (msg) => {
-      expect(msg.data.toString()).to.equal(data)
+      expect(uint8ArrayToString(msg.data)).to.equal(data)
       defer.resolve()
     })
 
diff --git a/test/pubsub/operation.node.js b/test/pubsub/operation.node.js
index 64a3d4e0..bf169cb3 100644
--- a/test/pubsub/operation.node.js
+++ b/test/pubsub/operation.node.js
@@ -10,6 +10,7 @@ const pWaitFor = require('p-wait-for')
 const pDefer = require('p-defer')
 const mergeOptions = require('merge-options')
 const multiaddr = require('multiaddr')
+const uint8ArrayToString = require('uint8arrays/to-string')
 
 const { create } = require('../../src')
 const { subsystemOptions, subsystemMulticodecs } = require('./utils')
@@ -82,7 +83,7 @@ describe('Pubsub subsystem operates correctly', () => {
       expect(subscribedTopics).to.not.include(topic)
 
       libp2p.pubsub.subscribe(topic, (msg) => {
-        expect(msg.data.toString()).to.equal(data)
+        expect(uint8ArrayToString(msg.data)).to.equal(data)
         defer.resolve()
       })
 
@@ -171,7 +172,7 @@ describe('Pubsub subsystem operates correctly', () => {
       expect(subscribedTopics).to.not.include(topic)
 
       libp2p.pubsub.subscribe(topic, (msg) => {
-        expect(msg.data.toString()).to.equal(data)
+        expect(uint8ArrayToString(msg.data)).to.equal(data)
         defer.resolve()
       })
 
@@ -242,7 +243,7 @@ describe('Pubsub subsystem operates correctly', () => {
       const defer1 = pDefer()
       const defer2 = pDefer()
       const handler = (msg) => {
-        expect(msg.data.toString()).to.equal(data)
+        expect(uint8ArrayToString(msg.data)).to.equal(data)
         counter++
         counter === 1 ? defer1.resolve() : defer2.resolve()
       }
@@ -307,7 +308,7 @@ describe('Pubsub subsystem operates correctly', () => {
       libp2p.pubsub.publish(topic, 'message1')
       remoteLibp2p.pubsub.publish(topic, 'message2')
       await pWaitFor(() => handlerSpy.callCount === 2)
-      expect(handlerSpy.args.map(([message]) => message.data.toString())).to.include.members(['message1', 'message2'])
+      expect(handlerSpy.args.map(([message]) => uint8ArrayToString(message.data))).to.include.members(['message1', 'message2'])
 
       // Disconnect the first connection (this acts as a delayed reconnect)
       await originalConnection.close()
@@ -317,7 +318,7 @@ describe('Pubsub subsystem operates correctly', () => {
       libp2p.pubsub.publish(topic, 'message3')
       remoteLibp2p.pubsub.publish(topic, 'message4')
       await pWaitFor(() => handlerSpy.callCount === 2)
-      expect(handlerSpy.args.map(([message]) => message.data.toString())).to.include.members(['message3', 'message4'])
+      expect(handlerSpy.args.map(([message]) => uint8ArrayToString(message.data))).to.include.members(['message3', 'message4'])
     })
   })
 })
diff --git a/test/record/envelope.spec.js b/test/record/envelope.spec.js
index 0b164252..7fbb23ad 100644
--- a/test/record/envelope.spec.js
+++ b/test/record/envelope.spec.js
@@ -4,6 +4,7 @@
 const chai = require('chai')
 chai.use(require('dirty-chai'))
 chai.use(require('chai-bytes'))
+chai.use(require('chai-as-promised'))
 const { expect } = chai
 
 const Envelope = require('../../src/record/envelope')
diff --git a/test/upgrading/upgrader.spec.js b/test/upgrading/upgrader.spec.js
index 2580cd5b..7282dcd1 100644
--- a/test/upgrading/upgrader.spec.js
+++ b/test/upgrading/upgrader.spec.js
@@ -1,11 +1,7 @@
 'use strict'
 /* eslint-env mocha */
 
-const { Buffer } = require('buffer')
-const chai = require('chai')
-chai.use(require('dirty-chai'))
-chai.use(require('chai-as-promised'))
-const { expect } = chai
+const { expect } = require('aegir/utils/chai')
 const sinon = require('sinon')
 const Muxer = require('libp2p-mplex')
 const multiaddr = require('multiaddr')
@@ -16,7 +12,8 @@ const pSettle = require('p-settle')
 const Transport = require('libp2p-websockets')
 const { NOISE: Crypto } = require('libp2p-noise')
 const Protector = require('../../src/pnet')
-const swarmKeyBuffer = Buffer.from(require('../fixtures/swarm.key'))
+const uint8ArrayFromString = require('uint8arrays/from-string')
+const swarmKeyBuffer = uint8ArrayFromString(require('../fixtures/swarm.key'))
 
 const Libp2p = require('../../src')
 const Upgrader = require('../../src/upgrader')
@@ -102,7 +99,7 @@ describe('Upgrader', () => {
     const { stream, protocol } = await connections[0].newStream('/echo/1.0.0')
     expect(protocol).to.equal('/echo/1.0.0')
 
-    const hello = Buffer.from('hello there!')
+    const hello = uint8ArrayFromString('hello there!')
     const result = await pipe(
       [hello],
       stream,
@@ -172,7 +169,7 @@ describe('Upgrader', () => {
     const { stream, protocol } = await connections[0].newStream('/echo/1.0.0')
     expect(protocol).to.equal('/echo/1.0.0')
 
-    const hello = Buffer.from('hello there!')
+    const hello = uint8ArrayFromString('hello there!')
     const result = await pipe(
       [hello],
       stream,