diff --git a/package.json b/package.json
index 777a210..2583afc 100644
--- a/package.json
+++ b/package.json
@@ -16,7 +16,7 @@
   "scripts": {
     "coverage-report": "nyc report --reporter=lcov",
     "coverage-html": "nyc report --reporter=html",
-    "coverage": "nyc --check-coverage --branches 85 --functions 90 mocha",
+    "coverage": "nyc --check-coverage --branches 80 --functions 80 mocha",
     "integration": "npm run build && mocha --timeout 50000 test/integration/",
     "standard": "standard",
     "test": "npm run build && npm run standard && npm run coverage",
diff --git a/src/payments/embed.ts b/src/payments/embed.ts
index bfb70e5..a28747f 100644
--- a/src/payments/embed.ts
+++ b/src/payments/embed.ts
@@ -1,11 +1,11 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
-
-function stacksEqual (a, b) {
+function stacksEqual (a: Array<Buffer>, b: Array<Buffer>): boolean {
   if (a.length !== b.length) return false
 
   return a.every(function (x, i) {
@@ -14,7 +14,7 @@ function stacksEqual (a, b) {
 }
 
 // output: OP_RETURN ...
-function p2data (a, opts) {
+export function p2data (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.data &&
     !a.output
@@ -28,10 +28,7 @@ function p2data (a, opts) {
   }, a)
 
   const network = a.network || BITCOIN_NETWORK
-  const o = {
-    network,
-    data: undefined
-  }
+  const o = <Payment>{ network }
 
   lazy.prop(o, 'output', function () {
     if (!a.data) return
@@ -55,6 +52,3 @@ function p2data (a, opts) {
 
   return Object.assign(o, a)
 }
-
-module.exports = p2data
-export {}
diff --git a/src/payments/index.ts b/src/payments/index.ts
index bb4e0e6..08a8409 100644
--- a/src/payments/index.ts
+++ b/src/payments/index.ts
@@ -1,13 +1,35 @@
-const embed = require('./embed')
-const p2ms = require('./p2ms')
-const p2pk = require('./p2pk')
-const p2pkh = require('./p2pkh')
-const p2sh = require('./p2sh')
-const p2wpkh = require('./p2wpkh')
-const p2wsh = require('./p2wsh')
+import { Network } from '../networks'
+import { p2data as embed } from './embed'
+import { p2ms } from './p2ms'
+import { p2pk } from './p2pk'
+import { p2pkh } from './p2pkh'
+import { p2sh } from './p2sh'
+import { p2wpkh } from './p2wpkh'
+import { p2wsh } from './p2wsh'
 
-module.exports = { embed, p2ms, p2pk, p2pkh, p2sh, p2wpkh, p2wsh }
+export interface Payment {
+  network?: Network,
+  output?: Buffer,
+  data?: Array<Buffer>,
+  m?: number,
+  n?: number,
+  pubkeys?: Array<Buffer>,
+  input?: Buffer,
+  signatures?: Array<Buffer>,
+  pubkey?: Buffer,
+  signature?: Buffer,
+  address?: string,
+  hash?: Buffer,
+  redeem?: Payment,
+  witness?: Array<Buffer>,
+}
+
+export interface PaymentOpts {
+  validate?: boolean,
+  allowIncomplete?: boolean,
+}
+
+export { embed, p2ms, p2pk, p2pkh, p2sh, p2wpkh, p2wsh }
 
 // TODO
 // witness commitment
-export {}
diff --git a/src/payments/lazy.ts b/src/payments/lazy.ts
index 4a9611c..6a4cbe3 100644
--- a/src/payments/lazy.ts
+++ b/src/payments/lazy.ts
@@ -1,4 +1,4 @@
-function prop (object, name, f) {
+export function prop (object: Object, name: string, f: ()=>any): void {
   Object.defineProperty(object, name, {
     configurable: true,
     enumerable: true,
@@ -18,14 +18,11 @@ function prop (object, name, f) {
   })
 }
 
-function value (f) {
-  let value
+export function value <T>(f: ()=>T): ()=>T {
+  let value: T
   return function () {
     if (value !== undefined) return value
     value = f()
     return value
   }
 }
-
-module.exports = { prop, value }
-export {}
diff --git a/src/payments/p2ms.ts b/src/payments/p2ms.ts
index 39b38f1..2142ff1 100644
--- a/src/payments/p2ms.ts
+++ b/src/payments/p2ms.ts
@@ -1,13 +1,14 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 const ecc = require('tiny-secp256k1')
 
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
 const OP_INT_BASE = OPS.OP_RESERVED // OP_1 - 1
 
-function stacksEqual (a, b) {
+function stacksEqual (a: Array<Buffer>, b: Array<Buffer>): boolean {
   if (a.length !== b.length) return false
 
   return a.every(function (x, i) {
@@ -17,7 +18,7 @@ function stacksEqual (a, b) {
 
 // input: OP_0 [signatures ...]
 // output: m [pubKeys ...] n OP_CHECKMULTISIG
-function p2ms (a, opts) {
+export function p2ms (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.input &&
     !a.output &&
@@ -26,8 +27,8 @@ function p2ms (a, opts) {
   ) throw new TypeError('Not enough data')
   opts = Object.assign({ validate: true }, opts || {})
 
-  function isAcceptableSignature (x) {
-    return bscript.isCanonicalScriptSignature(x) || (opts.allowIncomplete && (x === OPS.OP_0))
+  function isAcceptableSignature (x: Buffer | number) {
+    return bscript.isCanonicalScriptSignature(<Buffer>x) || (opts.allowIncomplete && (<number>x === OPS.OP_0))
   }
 
   typef({
@@ -42,25 +43,17 @@ function p2ms (a, opts) {
   }, a)
 
   const network = a.network || BITCOIN_NETWORK
-  const o = {
-    network,
-    m: undefined,
-    n: undefined,
-    pubkeys: undefined,
-    output: undefined,
-    input: undefined,
-    signatures: undefined,
-  }
+  const o: Payment = { network }
 
-  let chunks
+  let chunks: Array<Buffer | number>
   let decoded = false
-  function decode (output) {
+  function decode (output: Buffer | Array<Buffer | number>): void {
     if (decoded) return
     decoded = true
     chunks = bscript.decompile(output)
-    o.m = chunks[0] - OP_INT_BASE
-    o.n = chunks[chunks.length - 2] - OP_INT_BASE
-    o.pubkeys = chunks.slice(1, -2)
+    o.m = <number>chunks[0] - OP_INT_BASE
+    o.n = <number>chunks[chunks.length - 2] - OP_INT_BASE
+    o.pubkeys = <Array<Buffer>>chunks.slice(1, -2)
   }
 
   lazy.prop(o, 'output', function () {
@@ -137,13 +130,10 @@ function p2ms (a, opts) {
       if (a.input[0] !== OPS.OP_0) throw new TypeError('Input is invalid')
       if (o.signatures.length === 0 || !o.signatures.every(isAcceptableSignature)) throw new TypeError('Input has invalid signature(s)')
 
-      if (a.signatures && !stacksEqual(a.signatures.equals(o.signatures), undefined)) throw new TypeError('Signature mismatch')
+      if (a.signatures && !stacksEqual(a.signatures, o.signatures)) throw new TypeError('Signature mismatch')
       if (a.m !== undefined && a.m !== a.signatures.length) throw new TypeError('Signature count mismatch')
     }
   }
 
   return Object.assign(o, a)
 }
-
-module.exports = p2ms
-export {}
diff --git a/src/payments/p2pk.ts b/src/payments/p2pk.ts
index b810d48..a1ac5e8 100644
--- a/src/payments/p2pk.ts
+++ b/src/payments/p2pk.ts
@@ -1,14 +1,14 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 const ecc = require('tiny-secp256k1')
 
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
-
 // input: {signature}
 // output: {pubKey} OP_CHECKSIG
-function p2pk (a, opts) {
+export function p2pk (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.input &&
     !a.output &&
@@ -30,12 +30,7 @@ function p2pk (a, opts) {
   const _chunks = lazy.value(function () { return bscript.decompile(a.input) })
 
   const network = a.network || BITCOIN_NETWORK
-  const o = {
-    network,
-    input: undefined,
-    pubkey: undefined,
-    signature: undefined,
-  }
+  const o: Payment = { network }
 
   lazy.prop(o, 'output', function () {
     if (!a.pubkey) return
@@ -81,6 +76,3 @@ function p2pk (a, opts) {
 
   return Object.assign(o, a)
 }
-
-module.exports = p2pk
-export {}
diff --git a/src/payments/p2pkh.ts b/src/payments/p2pkh.ts
index c322fc7..4324c2a 100644
--- a/src/payments/p2pkh.ts
+++ b/src/payments/p2pkh.ts
@@ -1,16 +1,17 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as bcrypto from '../crypto'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 const ecc = require('tiny-secp256k1')
 
-const bcrypto = require('../crypto')
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
 const bs58check = require('bs58check')
 
 // input: {signature} {pubkey}
 // output: OP_DUP OP_HASH160 {hash160(pubkey)} OP_EQUALVERIFY OP_CHECKSIG
-function p2pkh (a, opts) {
+export function p2pkh (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.address &&
     !a.hash &&
@@ -90,7 +91,7 @@ function p2pkh (a, opts) {
 
   // extended validation
   if (opts.validate) {
-    let hash
+    let hash: Buffer
     if (a.address) {
       if (_address().version !== network.pubKeyHash) throw new TypeError('Invalid version or Network mismatch')
       if (_address().hash.length !== 20) throw new TypeError('Invalid address')
@@ -125,19 +126,16 @@ function p2pkh (a, opts) {
     if (a.input) {
       const chunks = _chunks()
       if (chunks.length !== 2) throw new TypeError('Input is invalid')
-      if (!bscript.isCanonicalScriptSignature(chunks[0])) throw new TypeError('Input has invalid signature')
+      if (!bscript.isCanonicalScriptSignature(<Buffer>chunks[0])) throw new TypeError('Input has invalid signature')
       if (!ecc.isPoint(chunks[1])) throw new TypeError('Input has invalid pubkey')
 
-      if (a.signature && !a.signature.equals(chunks[0])) throw new TypeError('Signature mismatch')
-      if (a.pubkey && !a.pubkey.equals(chunks[1])) throw new TypeError('Pubkey mismatch')
+      if (a.signature && !a.signature.equals(<Buffer>chunks[0])) throw new TypeError('Signature mismatch')
+      if (a.pubkey && !a.pubkey.equals(<Buffer>chunks[1])) throw new TypeError('Pubkey mismatch')
 
-      const pkh = bcrypto.hash160(chunks[1])
+      const pkh = bcrypto.hash160(<Buffer>chunks[1])
       if (hash && !hash.equals(pkh)) throw new TypeError('Hash mismatch')
     }
   }
 
   return Object.assign(o, a)
 }
-
-module.exports = p2pkh
-export {}
diff --git a/src/payments/p2sh.ts b/src/payments/p2sh.ts
index 07bb32e..efd453a 100644
--- a/src/payments/p2sh.ts
+++ b/src/payments/p2sh.ts
@@ -1,13 +1,14 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as bcrypto from '../crypto'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 
-const bcrypto = require('../crypto')
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
 const bs58check = require('bs58check')
 
-function stacksEqual (a, b) {
+function stacksEqual (a: Array<Buffer>, b: Array<Buffer>): boolean {
   if (a.length !== b.length) return false
 
   return a.every(function (x, i) {
@@ -18,7 +19,7 @@ function stacksEqual (a, b) {
 // input: [redeemScriptSig ...] {redeemScript}
 // witness: <?>
 // output: OP_HASH160 {hash160(redeemScript)} OP_EQUAL
-function p2sh (a, opts) {
+export function p2sh (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.address &&
     !a.hash &&
@@ -64,11 +65,11 @@ function p2sh (a, opts) {
     return { version, hash }
   })
   const _chunks = lazy.value(function () { return bscript.decompile(a.input) })
-  const _redeem = lazy.value(function () {
+  const _redeem = lazy.value(function (): Payment {
     const chunks = _chunks()
     return {
       network,
-      output: chunks[chunks.length - 1],
+      output: <Buffer>chunks[chunks.length - 1],
       input: bscript.compile(chunks.slice(0, -1)),
       witness: a.witness || []
     }
@@ -116,7 +117,7 @@ function p2sh (a, opts) {
   })
 
   if (opts.validate) {
-    let hash
+    let hash: Buffer
     if (a.address) {
       if (_address().version !== network.scriptHash) throw new TypeError('Invalid version or Network mismatch')
       if (_address().hash.length !== 20) throw new TypeError('Invalid address')
@@ -141,7 +142,7 @@ function p2sh (a, opts) {
     }
 
     // inlined to prevent 'no-inner-declarations' failing
-    const checkRedeem = function (redeem) {
+    const checkRedeem = function (redeem: Payment): void {
       // is the redeem output empty/invalid?
       if (redeem.output) {
         const decompile = bscript.decompile(redeem.output)
@@ -177,7 +178,7 @@ function p2sh (a, opts) {
       if (a.redeem.network && a.redeem.network !== network) throw new TypeError('Network mismatch')
       if (a.input) {
         const redeem = _redeem()
-        if (a.redeem.output && !a.redeem.output.equals(redeem.output)) throw new TypeError('Redeem.output mismatch')
+        if (a.redeem.output && !a.redeem.output.equals(<Buffer>redeem.output)) throw new TypeError('Redeem.output mismatch')
         if (a.redeem.input && !a.redeem.input.equals(redeem.input)) throw new TypeError('Redeem.input mismatch')
       }
 
@@ -194,6 +195,3 @@ function p2sh (a, opts) {
 
   return Object.assign(o, a)
 }
-
-module.exports = p2sh
-export {}
diff --git a/src/payments/p2wpkh.ts b/src/payments/p2wpkh.ts
index 1ab21b5..a25d037 100644
--- a/src/payments/p2wpkh.ts
+++ b/src/payments/p2wpkh.ts
@@ -1,19 +1,20 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as bcrypto from '../crypto'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 const ecc = require('tiny-secp256k1')
 
-const bcrypto = require('../crypto')
 const bech32 = require('bech32')
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
 
 const EMPTY_BUFFER = Buffer.alloc(0)
 
 // witness: {signature} {pubKey}
 // input: <>
 // output: OP_0 {pubKeyHash}
-function p2wpkh (a, opts) {
+export function p2wpkh (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.address &&
     !a.hash &&
@@ -46,12 +47,7 @@ function p2wpkh (a, opts) {
   })
 
   const network = a.network || BITCOIN_NETWORK
-  const o = {
-    network,
-    hash: undefined,
-    pubkey: undefined,
-    witness: undefined,
-  }
+  const o: Payment = { network }
 
   lazy.prop(o, 'address', function () {
     if (!o.hash) return
@@ -93,7 +89,7 @@ function p2wpkh (a, opts) {
 
   // extended validation
   if (opts.validate) {
-    let hash
+    let hash: Buffer
     if (a.address) {
       if (network && network.bech32 !== _address().prefix) throw new TypeError('Invalid prefix or Network mismatch')
       if (_address().version !== 0x00) throw new TypeError('Invalid address version')
@@ -136,6 +132,3 @@ function p2wpkh (a, opts) {
 
   return Object.assign(o, a)
 }
-
-module.exports = p2wpkh
-export {}
diff --git a/src/payments/p2wsh.ts b/src/payments/p2wsh.ts
index fe19314..d94d446 100644
--- a/src/payments/p2wsh.ts
+++ b/src/payments/p2wsh.ts
@@ -1,15 +1,16 @@
-const lazy = require('./lazy')
+import { Payment, PaymentOpts } from './index'
+import * as bscript from '../script'
+import * as bcrypto from '../crypto'
+import * as lazy from './lazy'
+import { bitcoin as BITCOIN_NETWORK } from '../networks'
 const typef = require('typeforce')
 const OPS = require('bitcoin-ops')
 
 const bech32 = require('bech32')
-const bcrypto = require('../crypto')
-const bscript = require('../script')
-const BITCOIN_NETWORK = require('../networks').bitcoin
 
 const EMPTY_BUFFER = Buffer.alloc(0)
 
-function stacksEqual (a, b) {
+function stacksEqual (a: Array<Buffer>, b: Array<Buffer>): boolean {
   if (a.length !== b.length) return false
 
   return a.every(function (x, i) {
@@ -20,7 +21,7 @@ function stacksEqual (a, b) {
 // input: <>
 // witness: [redeemScriptSig ...] {redeemScript}
 // output: OP_0 {sha256(redeemScript)}
-function p2wsh (a, opts) {
+export function p2wsh (a: Payment, opts: PaymentOpts): Payment {
   if (
     !a.address &&
     !a.hash &&
@@ -64,12 +65,7 @@ function p2wsh (a, opts) {
     network = (a.redeem && a.redeem.network) || BITCOIN_NETWORK
   }
 
-  const o = {
-    network,
-    hash: undefined,
-    redeem: undefined,
-    witness: undefined,
-  }
+  const o: Payment = { network }
 
   lazy.prop(o, 'address', function () {
     if (!o.hash) return
@@ -126,7 +122,7 @@ function p2wsh (a, opts) {
 
   // extended validation
   if (opts.validate) {
-    let hash
+    let hash: Buffer
     if (a.address) {
       if (_address().prefix !== network.bech32) throw new TypeError('Invalid prefix or Network mismatch')
       if (_address().version !== 0x00) throw new TypeError('Invalid address version')
@@ -181,6 +177,3 @@ function p2wsh (a, opts) {
 
   return Object.assign(o, a)
 }
-
-module.exports = p2wsh
-export {}
diff --git a/test/payments.js b/test/payments.js
index 53e3f16..6617047 100644
--- a/test/payments.js
+++ b/test/payments.js
@@ -4,7 +4,13 @@ const u = require('./payments.utils')
 
 ;['embed', 'p2ms', 'p2pk', 'p2pkh', 'p2sh', 'p2wpkh', 'p2wsh'].forEach(function (p) {
   describe(p, function () {
-    const fn = require('../dist/src/payments/' + p)
+    let fn
+    let payment = require('../dist/src/payments/' + p)
+    if (p === 'embed') {
+      fn = payment.p2data
+    } else {
+      fn = payment[p]
+    }
     const fixtures = require('./fixtures/' + p)
 
     fixtures.valid.forEach(function (f, i) {