diff --git a/packages/protons-benchmark/src/protons/rpc.ts b/packages/protons-benchmark/src/protons/rpc.ts
index 75781fd..a757885 100644
--- a/packages/protons-benchmark/src/protons/rpc.ts
+++ b/packages/protons-benchmark/src/protons/rpc.ts
@@ -115,7 +115,7 @@ export namespace RPC {
 
           if (opts.writeDefaults === true || obj.topic !== '') {
             w.uint32(34)
-            w.string(obj.topic)
+            w.string(obj.topic ?? '')
           }
 
           if (obj.signature != null) {
diff --git a/packages/protons-runtime/src/codec.ts b/packages/protons-runtime/src/codec.ts
index 367849a..c73fe80 100644
--- a/packages/protons-runtime/src/codec.ts
+++ b/packages/protons-runtime/src/codec.ts
@@ -16,7 +16,7 @@ export interface EncodeOptions {
 }
 
 export interface EncodeFunction<T> {
-  (value: T, writer: Writer, opts?: EncodeOptions): void
+  (value: Partial<T>, writer: Writer, opts?: EncodeOptions): void
 }
 
 export interface DecodeFunction<T> {
diff --git a/packages/protons-runtime/src/codecs/message.ts b/packages/protons-runtime/src/codecs/message.ts
index f7abf47..eca5171 100644
--- a/packages/protons-runtime/src/codecs/message.ts
+++ b/packages/protons-runtime/src/codecs/message.ts
@@ -6,6 +6,6 @@ export interface Factory<A, T> {
   new (obj: A): T
 }
 
-export function message <T> (encode: (obj: T, writer: Writer, opts?: EncodeOptions) => void, decode: (reader: Reader, length?: number) => T): Codec<T> {
+export function message <T> (encode: (obj: Partial<T>, writer: Writer, opts?: EncodeOptions) => void, decode: (reader: Reader, length?: number) => T): Codec<T> {
   return createCodec('message', CODEC_TYPES.LENGTH_DELIMITED, encode, decode)
 }
diff --git a/packages/protons/src/index.ts b/packages/protons/src/index.ts
index d26c19f..6f5744d 100644
--- a/packages/protons/src/index.ts
+++ b/packages/protons/src/index.ts
@@ -37,22 +37,22 @@ const types: Record<string, string> = {
   uint64: 'bigint'
 }
 
-const encoderGenerators: Record<string, (val: string) => string> = {
-  bool: (val) => `w.bool(${val})`,
-  bytes: (val) => `w.bytes(${val})`,
-  double: (val) => `w.double(${val})`,
-  fixed32: (val) => `w.fixed32(${val})`,
-  fixed64: (val) => `w.fixed64(${val})`,
-  float: (val) => `w.float(${val})`,
-  int32: (val) => `w.int32(${val})`,
-  int64: (val) => `w.int64(${val})`,
-  sfixed32: (val) => `w.sfixed32(${val})`,
-  sfixed64: (val) => `w.sfixed64(${val})`,
-  sint32: (val) => `w.sint32(${val})`,
-  sint64: (val) => `w.sint64(${val})`,
-  string: (val) => `w.string(${val})`,
-  uint32: (val) => `w.uint32(${val})`,
-  uint64: (val) => `w.uint64(${val})`
+const encoderGenerators: Record<string, (val: string, includeDefault: boolean) => string> = {
+  bool: (val, includeDefault) => `w.bool(${val}${includeDefault ? ' ?? false' : ''})`,
+  bytes: (val, includeDefault) => `w.bytes(${val}${includeDefault ? ' ?? new Uint8Array(0)' : ''})`,
+  double: (val, includeDefault) => `w.double(${val}${includeDefault ? ' ?? 0' : ''})`,
+  fixed32: (val, includeDefault) => `w.fixed32(${val}${includeDefault ? ' ?? 0' : ''})`,
+  fixed64: (val, includeDefault) => `w.fixed64(${val}${includeDefault ? ' ?? 0n' : ''})`,
+  float: (val, includeDefault) => `w.float(${val}${includeDefault ? ' ?? 0' : ''})`,
+  int32: (val, includeDefault) => `w.int32(${val}${includeDefault ? ' ?? 0' : ''})`,
+  int64: (val, includeDefault) => `w.int64(${val}${includeDefault ? ' ?? 0n' : ''})`,
+  sfixed32: (val, includeDefault) => `w.sfixed32(${val}${includeDefault ? ' ?? 0' : ''})`,
+  sfixed64: (val, includeDefault) => `w.sfixed64(${val}${includeDefault ? ' ?? 0n' : ''})`,
+  sint32: (val, includeDefault) => `w.sint32(${val}${includeDefault ? ' ?? 0' : ''})`,
+  sint64: (val, includeDefault) => `w.sint64(${val}${includeDefault ? ' ?? 0n' : ''})`,
+  string: (val, includeDefault) => `w.string(${val}${includeDefault ? ' ?? \'\'' : ''})`,
+  uint32: (val, includeDefault) => `w.uint32(${val}${includeDefault ? ' ?? 0' : ''})`,
+  uint64: (val, includeDefault) => `w.uint64(${val}${includeDefault ? ' ?? 0n' : ''})`
 }
 
 const decoderGenerators: Record<string, () => string> = {
@@ -92,21 +92,21 @@ const defaultValueGenerators: Record<string, () => string> = {
 }
 
 const defaultValueTestGenerators: Record<string, (field: string) => string> = {
-  bool: (field) => `${field} !== false`,
+  bool: (field) => `(${field} != null && ${field} !== false)`,
   bytes: (field) => `(${field} != null && ${field}.byteLength > 0)`,
-  double: (field) => `${field} !== 0`,
-  fixed32: (field) => `${field} !== 0`,
-  fixed64: (field) => `${field} !== 0n`,
-  float: (field) => `${field} !== 0`,
-  int32: (field) => `${field} !== 0`,
-  int64: (field) => `${field} !== 0n`,
-  sfixed32: (field) => `${field} !== 0`,
-  sfixed64: (field) => `${field} !== 0n`,
-  sint32: (field) => `${field} !== 0`,
-  sint64: (field) => `${field} !== 0n`,
-  string: (field) => `${field} !== ''`,
-  uint32: (field) => `${field} !== 0`,
-  uint64: (field) => `${field} !== 0n`
+  double: (field) => `(${field} != null && ${field} !== 0)`,
+  fixed32: (field) => `(${field} != null && ${field} !== 0)`,
+  fixed64: (field) => `(${field} != null && ${field} !== 0n)`,
+  float: (field) => `(${field} != null && ${field} !== 0)`,
+  int32: (field) => `(${field} != null && ${field} !== 0)`,
+  int64: (field) => `(${field} != null && ${field} !== 0n)`,
+  sfixed32: (field) => `(${field} != null && ${field} !== 0)`,
+  sfixed64: (field) => `(${field} != null && ${field} !== 0n)`,
+  sint32: (field) => `(${field} != null && ${field} !== 0)`,
+  sint64: (field) => `(${field} != null && ${field} !== 0n)`,
+  string: (field) => `(${field} != null && ${field} !== '')`,
+  uint32: (field) => `(${field} != null && ${field} !== 0)`,
+  uint64: (field) => `(${field} != null && ${field} !== 0n)`
 }
 
 function findTypeName (typeName: string, classDef: MessageDef, moduleDef: ModuleDef): string {
@@ -401,15 +401,26 @@ export interface ${messageDef.name} {
         }
       }
 
-      function createWriteField (valueVar: string): string {
+      function createWriteField (valueVar: string): (includeDefault: boolean) => string {
         const id = (fieldDef.id << 3) | codecTypes[type]
+        let defaultValue = ''
 
-        let writeField = `w.uint32(${id})
-          ${encoderGenerators[type] == null ? `${codec}.encode(${valueVar}, w)` : encoderGenerators[type](valueVar)}`
+        if (fieldDef.enum) {
+          const def = findDef(fieldDef.type, messageDef, moduleDef)
+
+          if (!isEnumDef(def)) {
+            throw new Error(`${fieldDef.type} was not enum def`)
+          }
+
+          defaultValue = Object.keys(def.values)[0]
+        }
+
+        let writeField = (includeDefault: boolean): string => `w.uint32(${id})
+          ${encoderGenerators[type] == null ? `${codec}.encode(${valueVar}${includeDefault ? ` ?? ${typeName}.${defaultValue}` : ''}, w)` : encoderGenerators[type](valueVar, includeDefault)}`
 
         if (type === 'message') {
           // message fields are only written if they have values
-          writeField = `w.uint32(${id})
+          writeField = () => `w.uint32(${id})
           ${typeName}.codec().encode(${valueVar}, w, {
             writeDefaults: ${Boolean(fieldDef.repeated).toString()}
           })`
@@ -422,10 +433,10 @@ export interface ${messageDef.name} {
 
       if (fieldDef.repeated) {
         if (fieldDef.map) {
-          writeField = `
+          writeField = () => `
         for (const [key, value] of obj.${name}.entries()) {
           ${
-              createWriteField('{ key, value }')
+              createWriteField('{ key, value }')(false)
                 .split('\n')
                 .map(s => {
                   const trimmed = s.trim()
@@ -437,10 +448,10 @@ export interface ${messageDef.name} {
           }
           `.trim()
         } else {
-          writeField = `
+          writeField = () => `
           for (const value of obj.${name}) {
           ${
-            createWriteField('value')
+            createWriteField('value')(false)
               .split('\n')
               .map(s => {
                 const trimmed = s.trim()
@@ -456,7 +467,7 @@ export interface ${messageDef.name} {
 
       return `
         if (${valueTest}) {
-          ${writeField}
+          ${writeField(valueTest.includes('opts.writeDefaults === true'))}
         }`
     }).join('\n')
 
@@ -537,7 +548,7 @@ ${encodeFields === '' ? '' : `${encodeFields}\n`}
     return _codec
   }
 
-  export const encode = (obj: ${messageDef.name}): Uint8Array => {
+  export const encode = (obj: Partial<${messageDef.name}>): Uint8Array => {
     return encodeMessage(obj, ${messageDef.name}.codec())
   }
 
diff --git a/packages/protons/test/fixtures/basic.ts b/packages/protons/test/fixtures/basic.ts
index e629eee..759c1e5 100644
--- a/packages/protons/test/fixtures/basic.ts
+++ b/packages/protons/test/fixtures/basic.ts
@@ -28,9 +28,9 @@ export namespace Basic {
           w.string(obj.foo)
         }
 
-        if (opts.writeDefaults === true || obj.num !== 0) {
+        if (opts.writeDefaults === true || (obj.num != null && obj.num !== 0)) {
           w.uint32(16)
-          w.int32(obj.num)
+          w.int32(obj.num ?? 0)
         }
 
         if (opts.lengthDelimited !== false) {
@@ -66,7 +66,7 @@ export namespace Basic {
     return _codec
   }
 
-  export const encode = (obj: Basic): Uint8Array => {
+  export const encode = (obj: Partial<Basic>): Uint8Array => {
     return encodeMessage(obj, Basic.codec())
   }
 
@@ -112,7 +112,7 @@ export namespace Empty {
     return _codec
   }
 
-  export const encode = (obj: Empty): Uint8Array => {
+  export const encode = (obj: Partial<Empty>): Uint8Array => {
     return encodeMessage(obj, Empty.codec())
   }
 
diff --git a/packages/protons/test/fixtures/circuit.proto b/packages/protons/test/fixtures/circuit.proto
index 1eaec2e..18c4535 100644
--- a/packages/protons/test/fixtures/circuit.proto
+++ b/packages/protons/test/fixtures/circuit.proto
@@ -29,7 +29,7 @@ message CircuitRelay {
   }
 
   message Peer {
-    required bytes id = 1;    // peer id
+    bytes id = 1;    // peer id
     repeated bytes addrs = 2; // peer's known addresses
   }
 
diff --git a/packages/protons/test/fixtures/circuit.ts b/packages/protons/test/fixtures/circuit.ts
index a0134c4..658f7ef 100644
--- a/packages/protons/test/fixtures/circuit.ts
+++ b/packages/protons/test/fixtures/circuit.ts
@@ -97,7 +97,7 @@ export namespace CircuitRelay {
 
           if (opts.writeDefaults === true || (obj.id != null && obj.id.byteLength > 0)) {
             w.uint32(10)
-            w.bytes(obj.id)
+            w.bytes(obj.id ?? new Uint8Array(0))
           }
 
           if (obj.addrs != null) {
@@ -141,7 +141,7 @@ export namespace CircuitRelay {
       return _codec
     }
 
-    export const encode = (obj: Peer): Uint8Array => {
+    export const encode = (obj: Partial<Peer>): Uint8Array => {
       return encodeMessage(obj, Peer.codec())
     }
 
@@ -220,7 +220,7 @@ export namespace CircuitRelay {
     return _codec
   }
 
-  export const encode = (obj: CircuitRelay): Uint8Array => {
+  export const encode = (obj: Partial<CircuitRelay>): Uint8Array => {
     return encodeMessage(obj, CircuitRelay.codec())
   }
 
diff --git a/packages/protons/test/fixtures/daemon.ts b/packages/protons/test/fixtures/daemon.ts
index 96b0eb2..8db6fee 100644
--- a/packages/protons/test/fixtures/daemon.ts
+++ b/packages/protons/test/fixtures/daemon.ts
@@ -64,7 +64,7 @@ export namespace Request {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          Request.Type.codec().encode(obj.type, w)
+          Request.Type.codec().encode(obj.type ?? Request.Type.IDENTIFY, w)
         }
 
         if (obj.connect != null) {
@@ -177,7 +177,7 @@ export namespace Request {
     return _codec
   }
 
-  export const encode = (obj: Request): Uint8Array => {
+  export const encode = (obj: Partial<Request>): Uint8Array => {
     return encodeMessage(obj, Request.codec())
   }
 
@@ -225,7 +225,7 @@ export namespace Response {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          Response.Type.codec().encode(obj.type, w)
+          Response.Type.codec().encode(obj.type ?? Response.Type.OK, w)
         }
 
         if (obj.error != null) {
@@ -331,7 +331,7 @@ export namespace Response {
     return _codec
   }
 
-  export const encode = (obj: Response): Uint8Array => {
+  export const encode = (obj: Partial<Response>): Uint8Array => {
     return encodeMessage(obj, Response.codec())
   }
 
@@ -357,7 +357,7 @@ export namespace IdentifyResponse {
 
         if (opts.writeDefaults === true || (obj.id != null && obj.id.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.id)
+          w.bytes(obj.id ?? new Uint8Array(0))
         }
 
         if (obj.addrs != null) {
@@ -401,7 +401,7 @@ export namespace IdentifyResponse {
     return _codec
   }
 
-  export const encode = (obj: IdentifyResponse): Uint8Array => {
+  export const encode = (obj: Partial<IdentifyResponse>): Uint8Array => {
     return encodeMessage(obj, IdentifyResponse.codec())
   }
 
@@ -428,7 +428,7 @@ export namespace ConnectRequest {
 
         if (opts.writeDefaults === true || (obj.peer != null && obj.peer.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.peer)
+          w.bytes(obj.peer ?? new Uint8Array(0))
         }
 
         if (obj.addrs != null) {
@@ -480,7 +480,7 @@ export namespace ConnectRequest {
     return _codec
   }
 
-  export const encode = (obj: ConnectRequest): Uint8Array => {
+  export const encode = (obj: Partial<ConnectRequest>): Uint8Array => {
     return encodeMessage(obj, ConnectRequest.codec())
   }
 
@@ -507,7 +507,7 @@ export namespace StreamOpenRequest {
 
         if (opts.writeDefaults === true || (obj.peer != null && obj.peer.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.peer)
+          w.bytes(obj.peer ?? new Uint8Array(0))
         }
 
         if (obj.proto != null) {
@@ -559,7 +559,7 @@ export namespace StreamOpenRequest {
     return _codec
   }
 
-  export const encode = (obj: StreamOpenRequest): Uint8Array => {
+  export const encode = (obj: Partial<StreamOpenRequest>): Uint8Array => {
     return encodeMessage(obj, StreamOpenRequest.codec())
   }
 
@@ -585,7 +585,7 @@ export namespace StreamHandlerRequest {
 
         if (opts.writeDefaults === true || (obj.addr != null && obj.addr.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.addr)
+          w.bytes(obj.addr ?? new Uint8Array(0))
         }
 
         if (obj.proto != null) {
@@ -629,7 +629,7 @@ export namespace StreamHandlerRequest {
     return _codec
   }
 
-  export const encode = (obj: StreamHandlerRequest): Uint8Array => {
+  export const encode = (obj: Partial<StreamHandlerRequest>): Uint8Array => {
     return encodeMessage(obj, StreamHandlerRequest.codec())
   }
 
@@ -652,9 +652,9 @@ export namespace ErrorResponse {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.msg !== '') {
+        if (opts.writeDefaults === true || (obj.msg != null && obj.msg !== '')) {
           w.uint32(10)
-          w.string(obj.msg)
+          w.string(obj.msg ?? '')
         }
 
         if (opts.lengthDelimited !== false) {
@@ -687,7 +687,7 @@ export namespace ErrorResponse {
     return _codec
   }
 
-  export const encode = (obj: ErrorResponse): Uint8Array => {
+  export const encode = (obj: Partial<ErrorResponse>): Uint8Array => {
     return encodeMessage(obj, ErrorResponse.codec())
   }
 
@@ -714,17 +714,17 @@ export namespace StreamInfo {
 
         if (opts.writeDefaults === true || (obj.peer != null && obj.peer.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.peer)
+          w.bytes(obj.peer ?? new Uint8Array(0))
         }
 
         if (opts.writeDefaults === true || (obj.addr != null && obj.addr.byteLength > 0)) {
           w.uint32(18)
-          w.bytes(obj.addr)
+          w.bytes(obj.addr ?? new Uint8Array(0))
         }
 
-        if (opts.writeDefaults === true || obj.proto !== '') {
+        if (opts.writeDefaults === true || (obj.proto != null && obj.proto !== '')) {
           w.uint32(26)
-          w.string(obj.proto)
+          w.string(obj.proto ?? '')
         }
 
         if (opts.lengthDelimited !== false) {
@@ -765,7 +765,7 @@ export namespace StreamInfo {
     return _codec
   }
 
-  export const encode = (obj: StreamInfo): Uint8Array => {
+  export const encode = (obj: Partial<StreamInfo>): Uint8Array => {
     return encodeMessage(obj, StreamInfo.codec())
   }
 
@@ -826,7 +826,7 @@ export namespace DHTRequest {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          DHTRequest.Type.codec().encode(obj.type, w)
+          DHTRequest.Type.codec().encode(obj.type ?? DHTRequest.Type.FIND_PEER, w)
         }
 
         if (obj.peer != null) {
@@ -907,7 +907,7 @@ export namespace DHTRequest {
     return _codec
   }
 
-  export const encode = (obj: DHTRequest): Uint8Array => {
+  export const encode = (obj: Partial<DHTRequest>): Uint8Array => {
     return encodeMessage(obj, DHTRequest.codec())
   }
 
@@ -952,7 +952,7 @@ export namespace DHTResponse {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          DHTResponse.Type.codec().encode(obj.type, w)
+          DHTResponse.Type.codec().encode(obj.type ?? DHTResponse.Type.BEGIN, w)
         }
 
         if (obj.peer != null) {
@@ -1003,7 +1003,7 @@ export namespace DHTResponse {
     return _codec
   }
 
-  export const encode = (obj: DHTResponse): Uint8Array => {
+  export const encode = (obj: Partial<DHTResponse>): Uint8Array => {
     return encodeMessage(obj, DHTResponse.codec())
   }
 
@@ -1029,7 +1029,7 @@ export namespace PeerInfo {
 
         if (opts.writeDefaults === true || (obj.id != null && obj.id.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.id)
+          w.bytes(obj.id ?? new Uint8Array(0))
         }
 
         if (obj.addrs != null) {
@@ -1073,7 +1073,7 @@ export namespace PeerInfo {
     return _codec
   }
 
-  export const encode = (obj: PeerInfo): Uint8Array => {
+  export const encode = (obj: Partial<PeerInfo>): Uint8Array => {
     return encodeMessage(obj, PeerInfo.codec())
   }
 
@@ -1119,7 +1119,7 @@ export namespace ConnManagerRequest {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          ConnManagerRequest.Type.codec().encode(obj.type, w)
+          ConnManagerRequest.Type.codec().encode(obj.type ?? ConnManagerRequest.Type.TAG_PEER, w)
         }
 
         if (obj.peer != null) {
@@ -1176,7 +1176,7 @@ export namespace ConnManagerRequest {
     return _codec
   }
 
-  export const encode = (obj: ConnManagerRequest): Uint8Array => {
+  export const encode = (obj: Partial<ConnManagerRequest>): Uint8Array => {
     return encodeMessage(obj, ConnManagerRequest.codec())
   }
 
@@ -1201,7 +1201,7 @@ export namespace DisconnectRequest {
 
         if (opts.writeDefaults === true || (obj.peer != null && obj.peer.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.peer)
+          w.bytes(obj.peer ?? new Uint8Array(0))
         }
 
         if (opts.lengthDelimited !== false) {
@@ -1234,7 +1234,7 @@ export namespace DisconnectRequest {
     return _codec
   }
 
-  export const encode = (obj: DisconnectRequest): Uint8Array => {
+  export const encode = (obj: Partial<DisconnectRequest>): Uint8Array => {
     return encodeMessage(obj, DisconnectRequest.codec())
   }
 
@@ -1281,7 +1281,7 @@ export namespace PSRequest {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          PSRequest.Type.codec().encode(obj.type, w)
+          PSRequest.Type.codec().encode(obj.type ?? PSRequest.Type.GET_TOPICS, w)
         }
 
         if (obj.topic != null) {
@@ -1330,7 +1330,7 @@ export namespace PSRequest {
     return _codec
   }
 
-  export const encode = (obj: PSRequest): Uint8Array => {
+  export const encode = (obj: Partial<PSRequest>): Uint8Array => {
     return encodeMessage(obj, PSRequest.codec())
   }
 
@@ -1435,7 +1435,7 @@ export namespace PSMessage {
     return _codec
   }
 
-  export const encode = (obj: PSMessage): Uint8Array => {
+  export const encode = (obj: Partial<PSMessage>): Uint8Array => {
     return encodeMessage(obj, PSMessage.codec())
   }
 
@@ -1507,7 +1507,7 @@ export namespace PSResponse {
     return _codec
   }
 
-  export const encode = (obj: PSResponse): Uint8Array => {
+  export const encode = (obj: Partial<PSResponse>): Uint8Array => {
     return encodeMessage(obj, PSResponse.codec())
   }
 
@@ -1552,7 +1552,7 @@ export namespace PeerstoreRequest {
 
         if (opts.writeDefaults === true || (obj.type != null && __TypeValues[obj.type] !== 0)) {
           w.uint32(8)
-          PeerstoreRequest.Type.codec().encode(obj.type, w)
+          PeerstoreRequest.Type.codec().encode(obj.type ?? PeerstoreRequest.Type.INVALID, w)
         }
 
         if (obj.id != null) {
@@ -1604,7 +1604,7 @@ export namespace PeerstoreRequest {
     return _codec
   }
 
-  export const encode = (obj: PeerstoreRequest): Uint8Array => {
+  export const encode = (obj: Partial<PeerstoreRequest>): Uint8Array => {
     return encodeMessage(obj, PeerstoreRequest.codec())
   }
 
@@ -1675,7 +1675,7 @@ export namespace PeerstoreResponse {
     return _codec
   }
 
-  export const encode = (obj: PeerstoreResponse): Uint8Array => {
+  export const encode = (obj: Partial<PeerstoreResponse>): Uint8Array => {
     return encodeMessage(obj, PeerstoreResponse.codec())
   }
 
diff --git a/packages/protons/test/fixtures/dht.ts b/packages/protons/test/fixtures/dht.ts
index f692c0c..9fcab58 100644
--- a/packages/protons/test/fixtures/dht.ts
+++ b/packages/protons/test/fixtures/dht.ts
@@ -91,7 +91,7 @@ export namespace Record {
     return _codec
   }
 
-  export const encode = (obj: Record): Uint8Array => {
+  export const encode = (obj: Partial<Record>): Uint8Array => {
     return encodeMessage(obj, Record.codec())
   }
 
@@ -225,7 +225,7 @@ export namespace Message {
       return _codec
     }
 
-    export const encode = (obj: Peer): Uint8Array => {
+    export const encode = (obj: Partial<Peer>): Uint8Array => {
       return encodeMessage(obj, Peer.codec())
     }
 
@@ -327,7 +327,7 @@ export namespace Message {
     return _codec
   }
 
-  export const encode = (obj: Message): Uint8Array => {
+  export const encode = (obj: Partial<Message>): Uint8Array => {
     return encodeMessage(obj, Message.codec())
   }
 
diff --git a/packages/protons/test/fixtures/maps.ts b/packages/protons/test/fixtures/maps.ts
index 8bd8a50..5295105 100644
--- a/packages/protons/test/fixtures/maps.ts
+++ b/packages/protons/test/fixtures/maps.ts
@@ -22,9 +22,9 @@ export namespace SubMessage {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.foo !== '') {
+        if (opts.writeDefaults === true || (obj.foo != null && obj.foo !== '')) {
           w.uint32(10)
-          w.string(obj.foo)
+          w.string(obj.foo ?? '')
         }
 
         if (opts.lengthDelimited !== false) {
@@ -57,7 +57,7 @@ export namespace SubMessage {
     return _codec
   }
 
-  export const encode = (obj: SubMessage): Uint8Array => {
+  export const encode = (obj: Partial<SubMessage>): Uint8Array => {
     return encodeMessage(obj, SubMessage.codec())
   }
 
@@ -89,14 +89,14 @@ export namespace MapTypes {
             w.fork()
           }
 
-          if (opts.writeDefaults === true || obj.key !== '') {
+          if (opts.writeDefaults === true || (obj.key != null && obj.key !== '')) {
             w.uint32(10)
-            w.string(obj.key)
+            w.string(obj.key ?? '')
           }
 
-          if (opts.writeDefaults === true || obj.value !== '') {
+          if (opts.writeDefaults === true || (obj.value != null && obj.value !== '')) {
             w.uint32(18)
-            w.string(obj.value)
+            w.string(obj.value ?? '')
           }
 
           if (opts.lengthDelimited !== false) {
@@ -133,7 +133,7 @@ export namespace MapTypes {
       return _codec
     }
 
-    export const encode = (obj: MapTypes$stringMapEntry): Uint8Array => {
+    export const encode = (obj: Partial<MapTypes$stringMapEntry>): Uint8Array => {
       return encodeMessage(obj, MapTypes$stringMapEntry.codec())
     }
 
@@ -157,14 +157,14 @@ export namespace MapTypes {
             w.fork()
           }
 
-          if (opts.writeDefaults === true || obj.key !== 0) {
+          if (opts.writeDefaults === true || (obj.key != null && obj.key !== 0)) {
             w.uint32(8)
-            w.int32(obj.key)
+            w.int32(obj.key ?? 0)
           }
 
-          if (opts.writeDefaults === true || obj.value !== 0) {
+          if (opts.writeDefaults === true || (obj.value != null && obj.value !== 0)) {
             w.uint32(16)
-            w.int32(obj.value)
+            w.int32(obj.value ?? 0)
           }
 
           if (opts.lengthDelimited !== false) {
@@ -201,7 +201,7 @@ export namespace MapTypes {
       return _codec
     }
 
-    export const encode = (obj: MapTypes$intMapEntry): Uint8Array => {
+    export const encode = (obj: Partial<MapTypes$intMapEntry>): Uint8Array => {
       return encodeMessage(obj, MapTypes$intMapEntry.codec())
     }
 
@@ -225,14 +225,14 @@ export namespace MapTypes {
             w.fork()
           }
 
-          if (opts.writeDefaults === true || obj.key !== false) {
+          if (opts.writeDefaults === true || (obj.key != null && obj.key !== false)) {
             w.uint32(8)
-            w.bool(obj.key)
+            w.bool(obj.key ?? false)
           }
 
-          if (opts.writeDefaults === true || obj.value !== false) {
+          if (opts.writeDefaults === true || (obj.value != null && obj.value !== false)) {
             w.uint32(16)
-            w.bool(obj.value)
+            w.bool(obj.value ?? false)
           }
 
           if (opts.lengthDelimited !== false) {
@@ -269,7 +269,7 @@ export namespace MapTypes {
       return _codec
     }
 
-    export const encode = (obj: MapTypes$boolMapEntry): Uint8Array => {
+    export const encode = (obj: Partial<MapTypes$boolMapEntry>): Uint8Array => {
       return encodeMessage(obj, MapTypes$boolMapEntry.codec())
     }
 
@@ -293,9 +293,9 @@ export namespace MapTypes {
             w.fork()
           }
 
-          if (opts.writeDefaults === true || obj.key !== '') {
+          if (opts.writeDefaults === true || (obj.key != null && obj.key !== '')) {
             w.uint32(10)
-            w.string(obj.key)
+            w.string(obj.key ?? '')
           }
 
           if (obj.value != null) {
@@ -339,7 +339,7 @@ export namespace MapTypes {
       return _codec
     }
 
-    export const encode = (obj: MapTypes$messageMapEntry): Uint8Array => {
+    export const encode = (obj: Partial<MapTypes$messageMapEntry>): Uint8Array => {
       return encodeMessage(obj, MapTypes$messageMapEntry.codec())
     }
 
@@ -443,7 +443,7 @@ export namespace MapTypes {
     return _codec
   }
 
-  export const encode = (obj: MapTypes): Uint8Array => {
+  export const encode = (obj: Partial<MapTypes>): Uint8Array => {
     return encodeMessage(obj, MapTypes.codec())
   }
 
diff --git a/packages/protons/test/fixtures/noise.ts b/packages/protons/test/fixtures/noise.ts
index 86e0417..204fef0 100644
--- a/packages/protons/test/fixtures/noise.ts
+++ b/packages/protons/test/fixtures/noise.ts
@@ -29,17 +29,17 @@ export namespace pb {
 
           if (opts.writeDefaults === true || (obj.identityKey != null && obj.identityKey.byteLength > 0)) {
             w.uint32(10)
-            w.bytes(obj.identityKey)
+            w.bytes(obj.identityKey ?? new Uint8Array(0))
           }
 
           if (opts.writeDefaults === true || (obj.identitySig != null && obj.identitySig.byteLength > 0)) {
             w.uint32(18)
-            w.bytes(obj.identitySig)
+            w.bytes(obj.identitySig ?? new Uint8Array(0))
           }
 
           if (opts.writeDefaults === true || (obj.data != null && obj.data.byteLength > 0)) {
             w.uint32(26)
-            w.bytes(obj.data)
+            w.bytes(obj.data ?? new Uint8Array(0))
           }
 
           if (opts.lengthDelimited !== false) {
@@ -80,7 +80,7 @@ export namespace pb {
       return _codec
     }
 
-    export const encode = (obj: NoiseHandshakePayload): Uint8Array => {
+    export const encode = (obj: Partial<NoiseHandshakePayload>): Uint8Array => {
       return encodeMessage(obj, NoiseHandshakePayload.codec())
     }
 
@@ -123,7 +123,7 @@ export namespace pb {
     return _codec
   }
 
-  export const encode = (obj: pb): Uint8Array => {
+  export const encode = (obj: Partial<pb>): Uint8Array => {
     return encodeMessage(obj, pb.codec())
   }
 
diff --git a/packages/protons/test/fixtures/optional.ts b/packages/protons/test/fixtures/optional.ts
index 91ff353..a882080 100644
--- a/packages/protons/test/fixtures/optional.ts
+++ b/packages/protons/test/fixtures/optional.ts
@@ -81,7 +81,7 @@ export namespace OptionalSubMessage {
     return _codec
   }
 
-  export const encode = (obj: OptionalSubMessage): Uint8Array => {
+  export const encode = (obj: Partial<OptionalSubMessage>): Uint8Array => {
     return encodeMessage(obj, OptionalSubMessage.codec())
   }
 
@@ -283,7 +283,7 @@ export namespace Optional {
     return _codec
   }
 
-  export const encode = (obj: Optional): Uint8Array => {
+  export const encode = (obj: Partial<Optional>): Uint8Array => {
     return encodeMessage(obj, Optional.codec())
   }
 
diff --git a/packages/protons/test/fixtures/peer.ts b/packages/protons/test/fixtures/peer.ts
index a55f9eb..0911b18 100644
--- a/packages/protons/test/fixtures/peer.ts
+++ b/packages/protons/test/fixtures/peer.ts
@@ -105,7 +105,7 @@ export namespace Peer {
     return _codec
   }
 
-  export const encode = (obj: Peer): Uint8Array => {
+  export const encode = (obj: Partial<Peer>): Uint8Array => {
     return encodeMessage(obj, Peer.codec())
   }
 
@@ -131,7 +131,7 @@ export namespace Address {
 
         if (opts.writeDefaults === true || (obj.multiaddr != null && obj.multiaddr.byteLength > 0)) {
           w.uint32(10)
-          w.bytes(obj.multiaddr)
+          w.bytes(obj.multiaddr ?? new Uint8Array(0))
         }
 
         if (obj.isCertified != null) {
@@ -172,7 +172,7 @@ export namespace Address {
     return _codec
   }
 
-  export const encode = (obj: Address): Uint8Array => {
+  export const encode = (obj: Partial<Address>): Uint8Array => {
     return encodeMessage(obj, Address.codec())
   }
 
@@ -196,14 +196,14 @@ export namespace Metadata {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.key !== '') {
+        if (opts.writeDefaults === true || (obj.key != null && obj.key !== '')) {
           w.uint32(10)
-          w.string(obj.key)
+          w.string(obj.key ?? '')
         }
 
         if (opts.writeDefaults === true || (obj.value != null && obj.value.byteLength > 0)) {
           w.uint32(18)
-          w.bytes(obj.value)
+          w.bytes(obj.value ?? new Uint8Array(0))
         }
 
         if (opts.lengthDelimited !== false) {
@@ -240,7 +240,7 @@ export namespace Metadata {
     return _codec
   }
 
-  export const encode = (obj: Metadata): Uint8Array => {
+  export const encode = (obj: Partial<Metadata>): Uint8Array => {
     return encodeMessage(obj, Metadata.codec())
   }
 
diff --git a/packages/protons/test/fixtures/singular.ts b/packages/protons/test/fixtures/singular.ts
index ff3a65d..2342c3a 100644
--- a/packages/protons/test/fixtures/singular.ts
+++ b/packages/protons/test/fixtures/singular.ts
@@ -40,14 +40,14 @@ export namespace SingularSubMessage {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.foo !== '') {
+        if (opts.writeDefaults === true || (obj.foo != null && obj.foo !== '')) {
           w.uint32(10)
-          w.string(obj.foo)
+          w.string(obj.foo ?? '')
         }
 
-        if (opts.writeDefaults === true || obj.bar !== 0) {
+        if (opts.writeDefaults === true || (obj.bar != null && obj.bar !== 0)) {
           w.uint32(16)
-          w.int32(obj.bar)
+          w.int32(obj.bar ?? 0)
         }
 
         if (opts.lengthDelimited !== false) {
@@ -84,7 +84,7 @@ export namespace SingularSubMessage {
     return _codec
   }
 
-  export const encode = (obj: SingularSubMessage): Uint8Array => {
+  export const encode = (obj: Partial<SingularSubMessage>): Uint8Array => {
     return encodeMessage(obj, SingularSubMessage.codec())
   }
 
@@ -123,84 +123,84 @@ export namespace Singular {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.double !== 0) {
+        if (opts.writeDefaults === true || (obj.double != null && obj.double !== 0)) {
           w.uint32(9)
-          w.double(obj.double)
+          w.double(obj.double ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.float !== 0) {
+        if (opts.writeDefaults === true || (obj.float != null && obj.float !== 0)) {
           w.uint32(21)
-          w.float(obj.float)
+          w.float(obj.float ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.int32 !== 0) {
+        if (opts.writeDefaults === true || (obj.int32 != null && obj.int32 !== 0)) {
           w.uint32(24)
-          w.int32(obj.int32)
+          w.int32(obj.int32 ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.int64 !== 0n) {
+        if (opts.writeDefaults === true || (obj.int64 != null && obj.int64 !== 0n)) {
           w.uint32(32)
-          w.int64(obj.int64)
+          w.int64(obj.int64 ?? 0n)
         }
 
-        if (opts.writeDefaults === true || obj.uint32 !== 0) {
+        if (opts.writeDefaults === true || (obj.uint32 != null && obj.uint32 !== 0)) {
           w.uint32(40)
-          w.uint32(obj.uint32)
+          w.uint32(obj.uint32 ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.uint64 !== 0n) {
+        if (opts.writeDefaults === true || (obj.uint64 != null && obj.uint64 !== 0n)) {
           w.uint32(48)
-          w.uint64(obj.uint64)
+          w.uint64(obj.uint64 ?? 0n)
         }
 
-        if (opts.writeDefaults === true || obj.sint32 !== 0) {
+        if (opts.writeDefaults === true || (obj.sint32 != null && obj.sint32 !== 0)) {
           w.uint32(56)
-          w.sint32(obj.sint32)
+          w.sint32(obj.sint32 ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.sint64 !== 0n) {
+        if (opts.writeDefaults === true || (obj.sint64 != null && obj.sint64 !== 0n)) {
           w.uint32(64)
-          w.sint64(obj.sint64)
+          w.sint64(obj.sint64 ?? 0n)
         }
 
-        if (opts.writeDefaults === true || obj.fixed32 !== 0) {
+        if (opts.writeDefaults === true || (obj.fixed32 != null && obj.fixed32 !== 0)) {
           w.uint32(77)
-          w.fixed32(obj.fixed32)
+          w.fixed32(obj.fixed32 ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.fixed64 !== 0n) {
+        if (opts.writeDefaults === true || (obj.fixed64 != null && obj.fixed64 !== 0n)) {
           w.uint32(81)
-          w.fixed64(obj.fixed64)
+          w.fixed64(obj.fixed64 ?? 0n)
         }
 
-        if (opts.writeDefaults === true || obj.sfixed32 !== 0) {
+        if (opts.writeDefaults === true || (obj.sfixed32 != null && obj.sfixed32 !== 0)) {
           w.uint32(93)
-          w.sfixed32(obj.sfixed32)
+          w.sfixed32(obj.sfixed32 ?? 0)
         }
 
-        if (opts.writeDefaults === true || obj.sfixed64 !== 0n) {
+        if (opts.writeDefaults === true || (obj.sfixed64 != null && obj.sfixed64 !== 0n)) {
           w.uint32(97)
-          w.sfixed64(obj.sfixed64)
+          w.sfixed64(obj.sfixed64 ?? 0n)
         }
 
-        if (opts.writeDefaults === true || obj.bool !== false) {
+        if (opts.writeDefaults === true || (obj.bool != null && obj.bool !== false)) {
           w.uint32(104)
-          w.bool(obj.bool)
+          w.bool(obj.bool ?? false)
         }
 
-        if (opts.writeDefaults === true || obj.string !== '') {
+        if (opts.writeDefaults === true || (obj.string != null && obj.string !== '')) {
           w.uint32(114)
-          w.string(obj.string)
+          w.string(obj.string ?? '')
         }
 
         if (opts.writeDefaults === true || (obj.bytes != null && obj.bytes.byteLength > 0)) {
           w.uint32(122)
-          w.bytes(obj.bytes)
+          w.bytes(obj.bytes ?? new Uint8Array(0))
         }
 
         if (opts.writeDefaults === true || (obj.enum != null && __SingularEnumValues[obj.enum] !== 0)) {
           w.uint32(128)
-          SingularEnum.codec().encode(obj.enum, w)
+          SingularEnum.codec().encode(obj.enum ?? SingularEnum.NO_VALUE, w)
         }
 
         if (obj.subMessage != null) {
@@ -303,7 +303,7 @@ export namespace Singular {
     return _codec
   }
 
-  export const encode = (obj: Singular): Uint8Array => {
+  export const encode = (obj: Partial<Singular>): Uint8Array => {
     return encodeMessage(obj, Singular.codec())
   }
 
diff --git a/packages/protons/test/fixtures/test.ts b/packages/protons/test/fixtures/test.ts
index 670d7c5..05849d8 100644
--- a/packages/protons/test/fixtures/test.ts
+++ b/packages/protons/test/fixtures/test.ts
@@ -37,9 +37,9 @@ export namespace SubMessage {
           w.fork()
         }
 
-        if (opts.writeDefaults === true || obj.foo !== '') {
+        if (opts.writeDefaults === true || (obj.foo != null && obj.foo !== '')) {
           w.uint32(10)
-          w.string(obj.foo)
+          w.string(obj.foo ?? '')
         }
 
         if (opts.lengthDelimited !== false) {
@@ -72,7 +72,7 @@ export namespace SubMessage {
     return _codec
   }
 
-  export const encode = (obj: SubMessage): Uint8Array => {
+  export const encode = (obj: Partial<SubMessage>): Uint8Array => {
     return encodeMessage(obj, SubMessage.codec())
   }
 
@@ -287,7 +287,7 @@ export namespace AllTheTypes {
     return _codec
   }
 
-  export const encode = (obj: AllTheTypes): Uint8Array => {
+  export const encode = (obj: Partial<AllTheTypes>): Uint8Array => {
     return encodeMessage(obj, AllTheTypes.codec())
   }
 
diff --git a/packages/protons/test/index.spec.ts b/packages/protons/test/index.spec.ts
index 7ad8c56..ebda6da 100644
--- a/packages/protons/test/index.spec.ts
+++ b/packages/protons/test/index.spec.ts
@@ -103,6 +103,7 @@ function normalizeProtonbufjs (obj: any, target: any): any {
 interface TestEncodingOptions {
   compareBytes?: boolean
   comparePbjs?: boolean
+  outputObject?: any
 }
 
 /**
@@ -111,32 +112,33 @@ interface TestEncodingOptions {
  * 1. the generated bytes between protons, pbjs and protobuf.js are the same
  * 2. protons and protobuf.js agree on deserialization
  */
-function testEncodings (obj: any, protons: any, proto: string, typeName: string, opts: TestEncodingOptions = {}): void {
+function testEncodings (inputObject: any, protons: any, proto: string, typeName: string, opts: TestEncodingOptions = {}): void {
+  const outputObject = opts.outputObject ?? inputObject
   const pbjsSchema = pbjs.parseSchema(fs.readFileSync(proto, 'utf-8')).compile()
-  const pbjsBuf = pbjsSchema[`encode${typeName}`](longifyBigInts(obj))
+  const pbjsBuf = pbjsSchema[`encode${typeName}`](longifyBigInts(inputObject))
 
   const protobufJsSchema = protobufjs.loadSync(proto).lookupType(typeName)
-  const protobufJsBuf = protobufJsSchema.encode(protobufJsSchema.fromObject(longifyBigInts(obj))).finish()
+  const protobufJsBuf = protobufJsSchema.encode(protobufJsSchema.fromObject(longifyBigInts(inputObject))).finish()
 
-  const encoded = protons.encode(obj)
+  const encoded = protons.encode(inputObject)
 
   if (opts.compareBytes !== false) {
     expect(encoded).to.equalBytes(pbjsBuf)
     expect(encoded).to.equalBytes(protobufJsBuf)
   }
 
-  expect(protons.decode(encoded)).to.deep.equal(obj)
-  expect(protons.decode(pbjsBuf)).to.deep.equal(obj)
-  expect(protons.decode(protobufJsBuf)).to.deep.equal(obj)
+  expect(protons.decode(encoded)).to.deep.equal(outputObject)
+  expect(protons.decode(pbjsBuf)).to.deep.equal(outputObject)
+  expect(protons.decode(protobufJsBuf)).to.deep.equal(outputObject)
 
   if (opts.comparePbjs !== false) {
-    expect(normalizePbjs(pbjsSchema[`decode${typeName}`](encoded), obj)).to.deep.equal(obj)
+    expect(normalizePbjs(pbjsSchema[`decode${typeName}`](encoded), inputObject)).to.deep.equal(outputObject)
   }
 
   expect(normalizeProtonbufjs(protobufJsSchema.toObject(protobufJsSchema.decode(encoded), {
     enums: String,
     defaults: true
-  }), obj)).to.deep.equal(obj)
+  }), inputObject)).to.deep.equal(outputObject)
 }
 
 describe('encode', () => {
@@ -384,6 +386,89 @@ describe('encode', () => {
     })
   })
 
+  it('does not require singular field values when set to defaults', () => {
+    const inputObject = {}
+    const outputObject: Singular = {
+      double: 0,
+      float: 0,
+      int32: 0,
+      int64: 0n,
+      uint32: 0,
+      uint64: 0n,
+      sint32: 0,
+      sint64: 0n,
+      fixed32: 0,
+      fixed64: 0n,
+      sfixed32: 0,
+      sfixed64: 0n,
+      bool: false,
+      string: '',
+      bytes: new Uint8Array(0),
+      enum: SingularEnum.NO_VALUE
+    }
+
+    testEncodings(inputObject, Singular, './test/fixtures/singular.proto', 'Singular', {
+      // protobuf.js writes default values for singular fields - https://github.com/protobufjs/protobuf.js/issues/1822
+      compareBytes: false,
+      // pbjs does not set default values when values are not present on the wire
+      comparePbjs: false,
+      // output object should have default values set
+      outputObject
+    })
+  })
+
+  it('does not write singular field values when defaults are omitted', () => {
+    const buf = Singular.encode({})
+
+    expect(buf.byteLength).to.equal(0, 'wrote default values for singular fields')
+
+    const outputObject: Singular = {
+      double: 0,
+      float: 0,
+      int32: 0,
+      int64: 0n,
+      uint32: 0,
+      uint64: 0n,
+      sint32: 0,
+      sint64: 0n,
+      fixed32: 0,
+      fixed64: 0n,
+      sfixed32: 0,
+      sfixed64: 0n,
+      bool: false,
+      string: '',
+      bytes: new Uint8Array(0),
+      enum: SingularEnum.NO_VALUE
+    }
+
+    expect(Singular.decode(buf)).to.deep.equal(outputObject)
+  })
+
+  it('does not write singular field values when set to defaults', () => {
+    const objectWithDefaults: Singular = {
+      double: 0,
+      float: 0,
+      int32: 0,
+      int64: 0n,
+      uint32: 0,
+      uint64: 0n,
+      sint32: 0,
+      sint64: 0n,
+      fixed32: 0,
+      fixed64: 0n,
+      sfixed32: 0,
+      sfixed64: 0n,
+      bool: false,
+      string: '',
+      bytes: new Uint8Array(0),
+      enum: SingularEnum.NO_VALUE
+    }
+
+    const buf = Singular.encode(objectWithDefaults)
+    expect(buf.byteLength).to.equal(0, 'wrote default values for singular fields')
+    expect(Singular.decode(buf)).to.deep.equal(objectWithDefaults)
+  })
+
   it('writes singular field values when not set to defaults', () => {
     const obj: Singular = {
       double: 1.0,