diff --git a/.eslintrc.json b/.eslintrc.json
index b1789709..e648de87 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -52,7 +52,7 @@
     "no-extra-semi": "off",
     "no-fallthrough": "off",
     "no-func-assign": "off",
-    "no-implicit-coercion": "off",
+    "no-implicit-coercion": "error",
     "no-multi-assign": "error",
     "no-multiple-empty-lines": ["error", {
       "max": 1
diff --git a/bin/cli b/bin/cli
index 332ffccf..1d37e4c4 100755
--- a/bin/cli
+++ b/bin/cli
@@ -173,7 +173,7 @@ CLI.prototype.getBlock = async function getBlock() {
   let hash = this.config.str(0);
 
   if (hash.length !== 64)
-    hash = +hash;
+    hash = parseInt(hash, 10);
 
   const block = await this.client.getBlock(hash);
 
@@ -386,7 +386,7 @@ CLI.prototype.reset = async function reset() {
   let hash = this.config.str(0);
 
   if (hash.length !== 64)
-    hash = +hash;
+    hash = parseInt(hash, 10);
 
   await this.client.reset(hash);
 
diff --git a/lib/blockchain/layout-browser.js b/lib/blockchain/layout-browser.js
index 7eb90bad..701a627b 100644
--- a/lib/blockchain/layout-browser.js
+++ b/lib/blockchain/layout-browser.js
@@ -49,7 +49,7 @@ const layout = {
   vv: function vv(key) {
     assert(typeof key === 'string');
     assert(key.length === 36);
-    return [+key.slice(1, 4), key.slice(4, 36)];
+    return [parseInt(key.slice(1, 4), 10), key.slice(4, 36)];
   },
   T: function T(addr, hash) {
     addr = hex(addr);
@@ -80,10 +80,10 @@ const layout = {
     let hash, index;
     if (key.length === 139) {
       hash = key.slice(65, 129);
-      index = +key.slice(129);
+      index = parseInt(key.slice(129), 10);
     } else if (key.length === 115) {
       hash = key.slice(41, 105);
-      index = +key.slice(105);
+      index = parseInt(key.slice(105), 10);
     } else {
       assert(false);
     }
diff --git a/lib/btc/amount.js b/lib/btc/amount.js
index a64e1e67..0dbdcd4d 100644
--- a/lib/btc/amount.js
+++ b/lib/btc/amount.js
@@ -365,7 +365,7 @@ Amount.serialize = function serialize(value, exp, num) {
     result = '-' + result;
 
   if (num)
-    return +result;
+    return Number(result);
 
   return result;
 };
@@ -385,7 +385,7 @@ Amount.serializeUnsafe = function serializeUnsafe(value, exp, num) {
   value = value.toFixed(exp);
 
   if (num)
-    return +value;
+    return Number(value);
 
   if (exp !== 0) {
     value = value.replace(/0+$/, '');
diff --git a/lib/crypto/secp256k1.js b/lib/crypto/secp256k1.js
index 32813306..d2ee2f83 100644
--- a/lib/crypto/secp256k1.js
+++ b/lib/crypto/secp256k1.js
@@ -8,7 +8,7 @@
 
 let native;
 
-if (+process.env.BCOIN_NO_SECP256K1 !== 1) {
+if (Number(process.env.BCOIN_NO_SECP256K1) !== 1) {
   try {
     native = require('secp256k1/bindings');
   } catch (e) {
diff --git a/lib/http/base.js b/lib/http/base.js
index 355aa435..917d68ab 100644
--- a/lib/http/base.js
+++ b/lib/http/base.js
@@ -1495,7 +1495,7 @@ Response.prototype.send = function send(code, msg, type) {
 
   if (typeof msg === 'string') {
     const len = Buffer.byteLength(msg, 'utf8');
-    this.setHeader('Content-Length', len + '');
+    this.setHeader('Content-Length', len.toString(10));
     try {
       this.write(msg, 'utf8');
       this.end();
@@ -1506,7 +1506,7 @@ Response.prototype.send = function send(code, msg, type) {
   }
 
   if (Buffer.isBuffer(msg)) {
-    this.setHeader('Content-Length', msg.length + '');
+    this.setHeader('Content-Length', msg.length.toString(10));
     try {
       this.write(msg);
       this.end();
diff --git a/lib/http/request.js b/lib/http/request.js
index bcc1da38..98fc6304 100644
--- a/lib/http/request.js
+++ b/lib/http/request.js
@@ -234,7 +234,7 @@ RequestOptions.prototype.getHeaders = function getHeaders() {
     headers['Content-Type'] = getType(this.type);
 
   if (this.body)
-    headers['Content-Length'] = this.body.length + '';
+    headers['Content-Length'] = this.body.length.toString(10);
 
   if (this.auth) {
     const auth = `${this.auth.username}:${this.auth.password}`;
diff --git a/lib/http/rpc.js b/lib/http/rpc.js
index 7e1441bb..fc0c74c8 100644
--- a/lib/http/rpc.js
+++ b/lib/http/rpc.js
@@ -2184,7 +2184,7 @@ RPC.prototype.handleLongpoll = async function handleLongpoll(lpid) {
     throw new RPCError(errs.INVALID_PARAMETER, 'Invalid longpoll ID.');
 
   const watched = lpid.slice(0, 64);
-  const lastTX = +lpid.slice(64, 74);
+  const lastTX = parseInt(lpid.slice(64, 74), 10);
 
   if (!util.isHex(watched) || !util.isUInt32(lastTX))
     throw new RPCError(errs.INVALID_PARAMETER, 'Invalid longpoll ID.');
@@ -2450,7 +2450,7 @@ RPC.prototype.getHashRate = async function getHashRate(lookup, height) {
 
   const workDiff = tip.chainwork.sub(entry.chainwork);
   const timeDiff = maxTime - minTime;
-  const ps = +workDiff.toString(10) / timeDiff;
+  const ps = parseInt(workDiff.toString(10), 10) / timeDiff;
 
   return ps;
 };
diff --git a/lib/http/rpcclient.js b/lib/http/rpcclient.js
index c7fd5302..75e869e6 100644
--- a/lib/http/rpcclient.js
+++ b/lib/http/rpcclient.js
@@ -86,7 +86,7 @@ function RPCError(msg, code) {
   Error.call(this);
 
   this.type = 'RPCError';
-  this.message = msg + '';
+  this.message = String(msg);
   this.code = code >>> 0;
 
   if (Error.captureStackTrace)
diff --git a/lib/http/server.js b/lib/http/server.js
index f8c6b589..09c2bf1e 100644
--- a/lib/http/server.js
+++ b/lib/http/server.js
@@ -262,7 +262,7 @@ HTTPServer.prototype.initRouter = function initRouter() {
     if (hash.length === 64)
       hash = util.revHex(hash);
     else
-      hash = +hash;
+      hash = parseInt(hash, 10);
 
     const block = await this.chain.db.getBlock(hash);
 
diff --git a/lib/native.js b/lib/native.js
index 0c9df733..cdd37639 100644
--- a/lib/native.js
+++ b/lib/native.js
@@ -8,7 +8,7 @@
 
 exports.binding = null;
 
-if (+process.env.BCOIN_NO_NATIVE !== 1) {
+if (Number(process.env.BCOIN_NO_NATIVE) !== 1) {
   try {
     exports.binding = require('bcoin-native');
   } catch (e) {
diff --git a/lib/net/packets.js b/lib/net/packets.js
index b5a77175..4c4d5c0a 100644
--- a/lib/net/packets.js
+++ b/lib/net/packets.js
@@ -1536,7 +1536,7 @@ RejectPacket.prototype.getCode = function getCode() {
   const code = RejectPacket.codesByVal[this.code];
 
   if (!code)
-    return this.code + '';
+    return this.code.toString(10);
 
   return code.toLowerCase();
 };
diff --git a/lib/net/upnp.js b/lib/net/upnp.js
index 84b60fbc..7a8293ca 100644
--- a/lib/net/upnp.js
+++ b/lib/net/upnp.js
@@ -374,7 +374,7 @@ UPNPService.prototype.soapRequest = async function soapRequest(action, args) {
     expect: 'xml',
     headers: {
       'Content-Type': 'text/xml; charset="utf-8"',
-      'Content-Length': Buffer.byteLength(req, 'utf8') + '',
+      'Content-Length': Buffer.byteLength(req, 'utf8').toString(10),
       'Connection': 'close',
       'SOAPAction': JSON.stringify(`${type}#${action}`)
     },
@@ -683,7 +683,7 @@ function findError(el) {
   const ccode = child.find('errorCode');
 
   if (ccode && /^\d+$/.test(ccode.text))
-    code = +ccode.text;
+    code = parseInt(ccode.text, 10);
 
   let desc = 'Unknown';
   const cdesc = child.find('errorDescription');
diff --git a/lib/node/logger.js b/lib/node/logger.js
index 747c8b24..6f8eb73c 100644
--- a/lib/node/logger.js
+++ b/lib/node/logger.js
@@ -45,7 +45,7 @@ function Logger(options) {
  * @const {Boolean}
  */
 
-Logger.HAS_TTY = !!(process.stdout && process.stdout.isTTY);
+Logger.HAS_TTY = Boolean(process.stdout && process.stdout.isTTY);
 
 /**
  * Maximum file size.
@@ -625,7 +625,7 @@ Logger.prototype.logError = function logError(level, module, err) {
       console.error(err);
   }
 
-  let msg = (err.message + '').replace(/^ *Error: */, '');
+  let msg = String(err.message).replace(/^ *Error: */, '');
 
   if (level !== Logger.levels.ERROR)
     msg = `Error: ${msg}`;
diff --git a/lib/primitives/abstractblock.js b/lib/primitives/abstractblock.js
index 5f3a50f6..cc2b5af8 100644
--- a/lib/primitives/abstractblock.js
+++ b/lib/primitives/abstractblock.js
@@ -72,7 +72,7 @@ AbstractBlock.prototype.parseOptions = function parseOptions(options) {
   this.nonce = options.nonce;
 
   if (options.mutable != null)
-    this.mutable = !!options.mutable;
+    this.mutable = Boolean(options.mutable);
 
   return this;
 };
diff --git a/lib/primitives/coin.js b/lib/primitives/coin.js
index f9e6a7f9..b5e73221 100644
--- a/lib/primitives/coin.js
+++ b/lib/primitives/coin.js
@@ -163,7 +163,7 @@ Coin.prototype.toKey = function toKey() {
 Coin.prototype.fromKey = function fromKey(key) {
   assert(key.length > 64);
   this.hash = key.slice(0, 64);
-  this.index = +key.slice(64);
+  this.index = parseInt(key.slice(64), 10);
   return this;
 };
 
diff --git a/lib/primitives/outpoint.js b/lib/primitives/outpoint.js
index 9195c61c..a23400ea 100644
--- a/lib/primitives/outpoint.js
+++ b/lib/primitives/outpoint.js
@@ -110,7 +110,7 @@ Outpoint.prototype.toKey = function toKey() {
 Outpoint.prototype.fromKey = function fromKey(key) {
   assert(key.length > 64);
   this.hash = key.slice(0, 64);
-  this.index = +key.slice(64);
+  this.index = parseInt(key.slice(64), 10);
   return this;
 };
 
diff --git a/lib/protocol/network.js b/lib/protocol/network.js
index 16d2144a..88599b43 100644
--- a/lib/protocol/network.js
+++ b/lib/protocol/network.js
@@ -100,7 +100,7 @@ Network.prototype._init = function _init() {
 
   for (const key of Object.keys(this.checkpointMap)) {
     const hash = this.checkpointMap[key];
-    const height = +key;
+    const height = Number(key);
 
     this.checkpoints.push({ hash: hash, height: height });
   }
diff --git a/lib/utils/lru.js b/lib/utils/lru.js
index e3378e97..b971ae3f 100644
--- a/lib/utils/lru.js
+++ b/lib/utils/lru.js
@@ -115,7 +115,7 @@ LRU.prototype.set = function set(key, value) {
   if (this.capacity === 0)
     return;
 
-  key = key + '';
+  key = String(key);
 
   let item = this.map.get(key);
 
@@ -151,7 +151,7 @@ LRU.prototype.get = function get(key) {
   if (this.capacity === 0)
     return null;
 
-  key = key + '';
+  key = String(key);
 
   const item = this.map.get(key);
 
@@ -173,7 +173,7 @@ LRU.prototype.get = function get(key) {
 LRU.prototype.has = function has(key) {
   if (this.capacity === 0)
     return false;
-  return this.map.has(key + '');
+  return this.map.has(String(key));
 };
 
 /**
@@ -186,7 +186,7 @@ LRU.prototype.remove = function remove(key) {
   if (this.capacity === 0)
     return false;
 
-  key = key + '';
+  key = String(key);
 
   const item = this.map.get(key);
 
diff --git a/lib/utils/util.js b/lib/utils/util.js
index 19e2cac5..843046db 100644
--- a/lib/utils/util.js
+++ b/lib/utils/util.js
@@ -315,7 +315,7 @@ util.fmt = nodeUtil.format;
 util.format = function format(args, color) {
   if (args.length > 0 && args[0] && typeof args[0] === 'object') {
     if (color == null)
-      color = !!(process.stdout && process.stdout.isTTY);
+      color = Boolean(process.stdout && process.stdout.isTTY);
     return util.inspectify(args[0], color);
   }
   return util.fmt(...args);
@@ -540,7 +540,7 @@ util.pad8 = function pad8(num) {
   assert(typeof num === 'number');
   assert(num >= 0);
 
-  num = num + '';
+  num = num.toString(10);
 
   switch (num.length) {
     case 1:
@@ -565,7 +565,7 @@ util.pad32 = function pad32(num) {
   assert(typeof num === 'number');
   assert(num >= 0);
 
-  num = num + '';
+  num = num.toString(10);
 
   switch (num.length) {
     case 1:
diff --git a/lib/wallet/account.js b/lib/wallet/account.js
index 70e492c4..4eb12c67 100644
--- a/lib/wallet/account.js
+++ b/lib/wallet/account.js
@@ -187,7 +187,7 @@ Account.prototype.fromOptions = function fromOptions(options) {
     this.type = Account.types.MULTISIG;
 
   if (!this.name)
-    this.name = this.accountIndex + '';
+    this.name = this.accountIndex.toString(10);
 
   if (this.m < 1 || this.m > this.n)
     throw new Error('m ranges between 1 and n');
diff --git a/lib/wallet/layout-browser.js b/lib/wallet/layout-browser.js
index 440dcf1b..cbaa13ff 100644
--- a/lib/wallet/layout-browser.js
+++ b/lib/wallet/layout-browser.js
@@ -42,7 +42,7 @@ layouts.walletdb = {
   },
   ww: function ww(key) {
     assert(typeof key === 'string');
-    return +key.slice(1);
+    return parseInt(key.slice(1), 10);
   },
   l: function l(id) {
     assert(typeof id === 'string');
@@ -61,7 +61,7 @@ layouts.walletdb = {
   },
   ii: function ii(key) {
     assert(typeof key === 'string');
-    return [+key.slice(1, 11), key.slice(11)];
+    return [parseInt(key.slice(1, 11), 10), key.slice(11)];
   },
   n: function n(wid, index) {
     return 'n' + pad32(wid) + pad32(index);
@@ -75,14 +75,14 @@ layouts.walletdb = {
   },
   bb: function bb(key) {
     assert(typeof key === 'string');
-    return +key.slice(1);
+    return parseInt(key.slice(1), 10);
   },
   o: function o(hash, index) {
     assert(typeof hash === 'string');
     return 'o' + hash + pad32(index);
   },
   oo: function oo(key) {
-    return [key.slice(1, 65), +key.slice(65)];
+    return [key.slice(1, 65), parseInt(key.slice(65), 10)];
   }
 };
 
@@ -94,7 +94,7 @@ layouts.txdb = {
   },
   pre: function pre(key) {
     assert(typeof key === 'string');
-    return +key.slice(1, 11);
+    return parseInt(key.slice(1, 11), 10);
   },
   R: 'R',
   hi: function hi(ch, hash, index) {
@@ -104,7 +104,7 @@ layouts.txdb = {
   hii: function hii(key) {
     assert(typeof key === 'string');
     key = key.slice(12);
-    return [key.slice(0, 64), +key.slice(64)];
+    return [key.slice(0, 64), parseInt(key.slice(64), 10)];
   },
   ih: function ih(ch, index, hash) {
     assert(typeof hash === 'string');
@@ -113,7 +113,7 @@ layouts.txdb = {
   ihh: function ihh(key) {
     assert(typeof key === 'string');
     key = key.slice(12);
-    return [+key.slice(0, 10), key.slice(10)];
+    return [parseInt(key.slice(0, 10), 10), key.slice(10)];
   },
   iih: function iih(ch, index, num, hash) {
     assert(typeof hash === 'string');
@@ -122,7 +122,11 @@ layouts.txdb = {
   iihh: function iihh(key) {
     assert(typeof key === 'string');
     key = key.slice(12);
-    return [+key.slice(0, 10), +key.slice(10, 20), key.slice(20)];
+    return [
+      parseInt(key.slice(0, 10), 10),
+      parseInt(key.slice(10, 20), 10),
+      key.slice(20)
+    ];
   },
   ihi: function ihi(ch, index, hash, num) {
     assert(typeof hash === 'string');
@@ -131,7 +135,11 @@ layouts.txdb = {
   ihii: function ihii(key) {
     assert(typeof key === 'string');
     key = key.slice(12);
-    return [+key.slice(0, 10), key.slice(10, 74), +key.slice(74)];
+    return [
+      parseInt(key.slice(0, 10), 10),
+      key.slice(10, 74),
+      parseInt(key.slice(74), 10)
+    ];
   },
   ha: function ha(ch, hash) {
     assert(typeof hash === 'string');
@@ -229,6 +237,6 @@ layouts.txdb = {
   bb: function bb(key) {
     assert(typeof key === 'string');
     key = key.slice(12);
-    return +key.slice(0);
+    return parseInt(key.slice(0), 10);
   }
 };
diff --git a/lib/wallet/wallet.js b/lib/wallet/wallet.js
index 13a9541e..7f62fe7e 100644
--- a/lib/wallet/wallet.js
+++ b/lib/wallet/wallet.js
@@ -671,7 +671,7 @@ Wallet.prototype._createAccount = async function _createAccount(options, passphr
   let name = options.name;
 
   if (!name)
-    name = this.accountDepth + '';
+    name = this.accountDepth.toString(10);
 
   if (await this.hasAccount(name))
     throw new Error('Account already exists.');
diff --git a/lib/workers/child.js b/lib/workers/child.js
index 8cc99543..6b1430aa 100644
--- a/lib/workers/child.js
+++ b/lib/workers/child.js
@@ -149,9 +149,9 @@ function listenExit(handler) {
 
   const onError = (err) => {
     if (err && err.stack)
-      console.error(err.stack + '');
+      console.error(String(err.stack));
     else
-      console.error(err + '');
+      console.error(String(err));
 
     process.exit(1);
   };
diff --git a/lib/workers/packets.js b/lib/workers/packets.js
index b8a96117..85113d58 100644
--- a/lib/workers/packets.js
+++ b/lib/workers/packets.js
@@ -176,8 +176,8 @@ ErrorPacket.prototype.cmd = packetTypes.ERROR;
 ErrorPacket.prototype.getSize = function getSize() {
   let size = 0;
 
-  size += encoding.sizeVarString(this.error.message + '', 'utf8');
-  size += encoding.sizeVarString(this.error.stack + '', 'utf8');
+  size += encoding.sizeVarString(String(this.error.message), 'utf8');
+  size += encoding.sizeVarString(String(this.error.stack), 'utf8');
   size += encoding.sizeVarString(this.error.type || '', 'utf8');
 
   switch (typeof this.error.code) {
@@ -198,8 +198,8 @@ ErrorPacket.prototype.getSize = function getSize() {
 };
 
 ErrorPacket.prototype.toWriter = function toWriter(bw) {
-  bw.writeVarString(this.error.message + '', 'utf8');
-  bw.writeVarString(this.error.stack + '', 'utf8');
+  bw.writeVarString(String(this.error.message), 'utf8');
+  bw.writeVarString(String(this.error.stack), 'utf8');
   bw.writeVarString(this.error.type || '', 'utf8');
 
   switch (typeof this.error.code) {
@@ -319,7 +319,7 @@ CheckResultPacket.prototype.getSize = function getSize() {
   size += 1;
   size += encoding.sizeVarString(err.code, 'utf8');
   size += encoding.sizeVarString(err.message, 'utf8');
-  size += encoding.sizeVarString(err.stack + '', 'utf8');
+  size += encoding.sizeVarString(String(err.stack), 'utf8');
   size += 1;
   size += 4;
 
@@ -337,7 +337,7 @@ CheckResultPacket.prototype.toWriter = function toWriter(bw) {
   bw.writeU8(1);
   bw.writeVarString(err.code, 'utf8');
   bw.writeVarString(err.message, 'utf8');
-  bw.writeVarString(err.stack + '', 'utf8');
+  bw.writeVarString(String(err.stack), 'utf8');
   bw.writeU8(err.op === -1 ? 0xff : err.op);
   bw.writeU32(err.ip === -1 ? 0xffffffff : err.ip);
 };
diff --git a/migrate/walletdb2to3.js b/migrate/walletdb2to3.js
index e8e9b09a..381cb976 100644
--- a/migrate/walletdb2to3.js
+++ b/migrate/walletdb2to3.js
@@ -73,7 +73,7 @@ async function updatePathMap() {
     const keys = Object.keys(oldPaths);
 
     for (let i = 0; i < keys.length; i++) {
-      keys[i] = +keys[i];
+      keys[i] = Number(keys[i]);
       const key = keys[i];
       const oldPath = oldPaths[key];
       const path = new Path(oldPath);