diff --git a/Dockerfile.tools b/Dockerfile.tools
index cfed215a1..ccac4ba96 100644
--- a/Dockerfile.tools
+++ b/Dockerfile.tools
@@ -21,7 +21,8 @@ ARG protobuf=3.8.0
 RUN wget -q https://github.com/protocolbuffers/protobuf/releases/download/v$protobuf/protoc-$protobuf-linux-x86_64.zip -O /tmp/protobuf.zip && \
     mkdir /tmp/protobuf && \
     unzip /tmp/protobuf.zip -d /tmp/protobuf && \
-    mv /tmp/protobuf/bin/protoc /usr/local/bin/protoc && \
+    mv /tmp/protobuf/bin/* /usr/local/bin/ && \
+    mv /tmp/protobuf/include/* /usr/local/include/ && \
     rm -rf /tmp/*
 
 RUN go install github.com/go-bindata/go-bindata/go-bindata
diff --git a/protobuf/api/event.pb.go b/protobuf/api/event.pb.go
index 0f2ede966..a94fec8a7 100644
--- a/protobuf/api/event.pb.go
+++ b/protobuf/api/event.pb.go
@@ -7,6 +7,7 @@ import (
 	context "context"
 	fmt "fmt"
 	proto "github.com/golang/protobuf/proto"
+	_struct "github.com/golang/protobuf/ptypes/struct"
 	types "github.com/mesg-foundation/engine/protobuf/types"
 	grpc "google.golang.org/grpc"
 	math "math"
@@ -130,10 +131,10 @@ type CreateEventRequest struct {
 	// key is the key of the event.
 	Key string `protobuf:"bytes,2,opt,name=key,proto3" json:"key,omitempty"`
 	// data is the data for the event.
-	Data                 string   `protobuf:"bytes,3,opt,name=data,proto3" json:"data,omitempty"`
-	XXX_NoUnkeyedLiteral struct{} `json:"-"`
-	XXX_unrecognized     []byte   `json:"-"`
-	XXX_sizecache        int32    `json:"-"`
+	Data                 *_struct.Struct `protobuf:"bytes,3,opt,name=data,proto3" json:"data,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}        `json:"-"`
+	XXX_unrecognized     []byte          `json:"-"`
+	XXX_sizecache        int32           `json:"-"`
 }
 
 func (m *CreateEventRequest) Reset()         { *m = CreateEventRequest{} }
@@ -175,11 +176,11 @@ func (m *CreateEventRequest) GetKey() string {
 	return ""
 }
 
-func (m *CreateEventRequest) GetData() string {
+func (m *CreateEventRequest) GetData() *_struct.Struct {
 	if m != nil {
 		return m.Data
 	}
-	return ""
+	return nil
 }
 
 // CreateEventResponse defines response for execution update.
@@ -233,24 +234,25 @@ func init() {
 func init() { proto.RegisterFile("protobuf/api/event.proto", fileDescriptor_c0ad091fa003d2ac) }
 
 var fileDescriptor_c0ad091fa003d2ac = []byte{
-	// 260 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x74, 0x91, 0x41, 0x4b, 0xc3, 0x40,
-	0x10, 0x85, 0xbb, 0x8d, 0x2e, 0x38, 0xf6, 0x20, 0xe3, 0xc1, 0xb0, 0x07, 0x91, 0x3d, 0xe9, 0x65,
-	0x2b, 0x2d, 0x78, 0xf3, 0x24, 0x8a, 0xe7, 0x78, 0x17, 0xb6, 0x3a, 0xa5, 0x8b, 0x9a, 0xac, 0xd9,
-	0xa9, 0x50, 0xfc, 0x33, 0xfe, 0x54, 0xc9, 0x24, 0x04, 0x63, 0xf4, 0x36, 0xbc, 0xf7, 0xe6, 0x63,
-	0xf6, 0x2d, 0xe4, 0xb1, 0xae, 0xb8, 0x5a, 0x6d, 0xd7, 0x73, 0x1f, 0xc3, 0x9c, 0x3e, 0xa8, 0x64,
-	0x27, 0x12, 0x66, 0x3e, 0x06, 0x63, 0x7a, 0x9b, 0x77, 0x91, 0xd2, 0xcf, 0x80, 0xfd, 0x52, 0x80,
-	0x0f, 0x5c, 0x93, 0x7f, 0xbb, 0x6d, 0xd4, 0x82, 0xde, 0xb7, 0x94, 0x18, 0xaf, 0x40, 0xaf, 0xc3,
-	0x2b, 0x53, 0x9d, 0xab, 0x33, 0x75, 0x7e, 0xb8, 0x38, 0x75, 0x3e, 0x06, 0x37, 0x0e, 0xba, 0x3b,
-	0x49, 0x15, 0x5d, 0xda, 0x14, 0xa0, 0x5b, 0x05, 0x11, 0xf6, 0x36, 0x3e, 0x6d, 0x64, 0xff, 0xa0,
-	0x90, 0x19, 0x2d, 0xcc, 0x42, 0x99, 0xd8, 0x97, 0x4f, 0x74, 0xdf, 0x78, 0x53, 0xf1, 0x06, 0x1a,
-	0x1e, 0x41, 0xf6, 0x42, 0xbb, 0x3c, 0x13, 0xab, 0x19, 0xed, 0x23, 0xe0, 0x4d, 0x4d, 0x9e, 0x69,
-	0x70, 0xe1, 0x6f, 0x96, 0xfa, 0x9f, 0x35, 0xed, 0x59, 0xcd, 0x55, 0xcf, 0x9e, 0x7d, 0x87, 0x97,
-	0xd9, 0x5e, 0xc0, 0xf1, 0x80, 0x9f, 0x62, 0x55, 0x26, 0xfa, 0xeb, 0x01, 0x8b, 0x4f, 0xd8, 0x97,
-	0x10, 0x5e, 0x83, 0x6e, 0x77, 0xf0, 0x44, 0x9a, 0x19, 0x1f, 0x68, 0xf2, 0xb1, 0xd1, 0x92, 0xed,
-	0x04, 0x97, 0xa0, 0xdb, 0x2e, 0xbb, 0xf5, 0x71, 0xb1, 0x66, 0xe6, 0xe4, 0xb3, 0x9c, 0x88, 0x76,
-	0x72, 0xa9, 0x56, 0x5a, 0x7e, 0x6c, 0xf9, 0x1d, 0x00, 0x00, 0xff, 0xff, 0x58, 0x6b, 0x0c, 0x12,
-	0xee, 0x01, 0x00, 0x00,
+	// 287 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x74, 0x51, 0xcd, 0x4a, 0xc3, 0x40,
+	0x10, 0x6e, 0xda, 0x1a, 0x70, 0xda, 0x83, 0x8c, 0x87, 0x86, 0x45, 0x44, 0xf6, 0xa4, 0x08, 0x5b,
+	0x69, 0xc1, 0x9b, 0x27, 0x51, 0x3c, 0xc7, 0x27, 0xd8, 0xc6, 0x69, 0x1b, 0xac, 0xc9, 0x9a, 0x9d,
+	0x28, 0xc5, 0x97, 0xf1, 0x51, 0x25, 0x93, 0x18, 0x8c, 0xd1, 0xdb, 0xf0, 0xfd, 0xed, 0xcc, 0xb7,
+	0x10, 0xb9, 0x22, 0xe7, 0x7c, 0x55, 0xae, 0xe7, 0xd6, 0xa5, 0x73, 0x7a, 0xa3, 0x8c, 0x8d, 0x40,
+	0x38, 0xb2, 0x2e, 0x55, 0x27, 0x9b, 0x3c, 0xdf, 0xec, 0x68, 0xde, 0xaa, 0x3c, 0x17, 0x65, 0xd2,
+	0x48, 0x94, 0x6a, 0x61, 0xde, 0x3b, 0xf2, 0x3f, 0xed, 0xfa, 0x33, 0x00, 0x7c, 0xe4, 0x82, 0xec,
+	0xcb, 0x5d, 0x85, 0xc6, 0xf4, 0x5a, 0x92, 0x67, 0xbc, 0x86, 0x70, 0x9d, 0xee, 0x98, 0x8a, 0x28,
+	0x38, 0x0b, 0xce, 0x27, 0x8b, 0x53, 0x63, 0x5d, 0x6a, 0xfa, 0x42, 0x73, 0x2f, 0xaa, 0xb8, 0x51,
+	0xab, 0x18, 0xc2, 0x1a, 0x41, 0x84, 0xf1, 0xd6, 0xfa, 0xad, 0xf8, 0x0f, 0x63, 0x99, 0x51, 0xc3,
+	0x34, 0xcd, 0x3c, 0xdb, 0x2c, 0xa1, 0x87, 0x8a, 0x1b, 0x0a, 0xd7, 0xc1, 0xf0, 0x08, 0x46, 0xcf,
+	0xb4, 0x8f, 0x46, 0x42, 0x55, 0xa3, 0x7e, 0x07, 0xbc, 0x2d, 0xc8, 0x32, 0x75, 0x36, 0xfc, 0x9d,
+	0x15, 0xfc, 0x9f, 0x35, 0x6c, 0xb3, 0xf0, 0x12, 0xc6, 0x4f, 0x96, 0xad, 0xc4, 0x4f, 0x16, 0x33,
+	0x53, 0xf7, 0x66, 0xbe, 0x0b, 0xaa, 0x2e, 0x2c, 0x13, 0x8e, 0x45, 0xa4, 0x2f, 0xe0, 0xb8, 0xf3,
+	0xb0, 0x77, 0x79, 0xe6, 0xe9, 0xaf, 0xcb, 0x16, 0x1f, 0x70, 0x20, 0x22, 0xbc, 0x81, 0xb0, 0xf6,
+	0xe0, 0x4c, 0x2a, 0xeb, 0x6f, 0xae, 0xa2, 0x3e, 0x51, 0x27, 0xeb, 0x01, 0x2e, 0x21, 0xac, 0x4b,
+	0x6e, 0xec, 0xfd, 0xc6, 0xd5, 0xd4, 0xc8, 0x2f, 0x1a, 0x01, 0xf5, 0xe0, 0x2a, 0x58, 0x85, 0xb2,
+	0xfe, 0xf2, 0x2b, 0x00, 0x00, 0xff, 0xff, 0x68, 0x3c, 0x8a, 0x99, 0x25, 0x02, 0x00, 0x00,
 }
 
 // Reference imports to suppress errors if they are not otherwise used.
diff --git a/protobuf/api/event.proto b/protobuf/api/event.proto
index fddb0d8bb..e8920bf0e 100644
--- a/protobuf/api/event.proto
+++ b/protobuf/api/event.proto
@@ -1,5 +1,6 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
 import "protobuf/types/event.proto";
 
 package api;
@@ -45,7 +46,7 @@ message CreateEventRequest {
   string key = 2;
 
   // data is the data for the event.
-  string data = 3;
+  google.protobuf.Struct data = 3;
 }
 
 // CreateEventResponse defines response for execution update.
diff --git a/protobuf/api/execution.pb.go b/protobuf/api/execution.pb.go
index 97185b4d2..25ed7fa9f 100644
--- a/protobuf/api/execution.pb.go
+++ b/protobuf/api/execution.pb.go
@@ -7,6 +7,7 @@ import (
 	context "context"
 	fmt "fmt"
 	proto "github.com/golang/protobuf/proto"
+	_struct "github.com/golang/protobuf/ptypes/struct"
 	types "github.com/mesg-foundation/engine/protobuf/types"
 	grpc "google.golang.org/grpc"
 	math "math"
@@ -25,13 +26,13 @@ const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
 
 // CreateExecutionRequest defines request to create a single execution.
 type CreateExecutionRequest struct {
-	InstanceHash         string   `protobuf:"bytes,1,opt,name=instanceHash,proto3" json:"instanceHash,omitempty"`
-	TaskKey              string   `protobuf:"bytes,2,opt,name=taskKey,proto3" json:"taskKey,omitempty"`
-	Inputs               string   `protobuf:"bytes,3,opt,name=inputs,proto3" json:"inputs,omitempty"`
-	Tags                 []string `protobuf:"bytes,4,rep,name=tags,proto3" json:"tags,omitempty"`
-	XXX_NoUnkeyedLiteral struct{} `json:"-"`
-	XXX_unrecognized     []byte   `json:"-"`
-	XXX_sizecache        int32    `json:"-"`
+	InstanceHash         string          `protobuf:"bytes,1,opt,name=instanceHash,proto3" json:"instanceHash,omitempty"`
+	TaskKey              string          `protobuf:"bytes,2,opt,name=taskKey,proto3" json:"taskKey,omitempty"`
+	Inputs               *_struct.Struct `protobuf:"bytes,3,opt,name=inputs,proto3" json:"inputs,omitempty"`
+	Tags                 []string        `protobuf:"bytes,4,rep,name=tags,proto3" json:"tags,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}        `json:"-"`
+	XXX_unrecognized     []byte          `json:"-"`
+	XXX_sizecache        int32           `json:"-"`
 }
 
 func (m *CreateExecutionRequest) Reset()         { *m = CreateExecutionRequest{} }
@@ -73,11 +74,11 @@ func (m *CreateExecutionRequest) GetTaskKey() string {
 	return ""
 }
 
-func (m *CreateExecutionRequest) GetInputs() string {
+func (m *CreateExecutionRequest) GetInputs() *_struct.Struct {
 	if m != nil {
 		return m.Inputs
 	}
-	return ""
+	return nil
 }
 
 func (m *CreateExecutionRequest) GetTags() []string {
@@ -330,7 +331,7 @@ type isUpdateExecutionRequest_Result interface {
 }
 
 type UpdateExecutionRequest_Outputs struct {
-	Outputs string `protobuf:"bytes,2,opt,name=outputs,proto3,oneof"`
+	Outputs *_struct.Struct `protobuf:"bytes,2,opt,name=outputs,proto3,oneof"`
 }
 
 type UpdateExecutionRequest_Error struct {
@@ -348,11 +349,11 @@ func (m *UpdateExecutionRequest) GetResult() isUpdateExecutionRequest_Result {
 	return nil
 }
 
-func (m *UpdateExecutionRequest) GetOutputs() string {
+func (m *UpdateExecutionRequest) GetOutputs() *_struct.Struct {
 	if x, ok := m.GetResult().(*UpdateExecutionRequest_Outputs); ok {
 		return x.Outputs
 	}
-	return ""
+	return nil
 }
 
 func (m *UpdateExecutionRequest) GetError() string {
@@ -415,32 +416,34 @@ func init() {
 func init() { proto.RegisterFile("protobuf/api/execution.proto", fileDescriptor_96e2c86581f82f05) }
 
 var fileDescriptor_96e2c86581f82f05 = []byte{
-	// 401 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x7c, 0x53, 0x4d, 0xaf, 0xd2, 0x40,
-	0x14, 0x6d, 0x29, 0x16, 0xb8, 0x7e, 0xc4, 0x8c, 0x49, 0xa9, 0x95, 0x18, 0x32, 0x2b, 0x58, 0x58,
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+	// 433 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x7c, 0x52, 0xc1, 0x6e, 0x13, 0x31,
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+	0x32, 0x83, 0xd6, 0x1d, 0x48, 0x3c, 0x83, 0xe9, 0xc0, 0x44, 0xa8, 0x6f, 0xf5, 0x73, 0x04, 0xe3,
+	0x1e, 0xe5, 0xe7, 0x90, 0x85, 0x9e, 0xf9, 0x73, 0x1f, 0x76, 0xfc, 0x47, 0x16, 0xb3, 0x38, 0x19,
+	0x8e, 0x14, 0x09, 0x5f, 0x43, 0x7a, 0x81, 0xc4, 0x73, 0x2f, 0x8b, 0xfc, 0x84, 0xe2, 0x49, 0xdb,
+	0x40, 0x4f, 0x88, 0x84, 0xbf, 0x81, 0x2c, 0x74, 0xdb, 0xde, 0x1d, 0x2f, 0x3a, 0x36, 0xfa, 0x8a,
+	0xdd, 0x1a, 0x0f, 0x2f, 0x6c, 0x87, 0xe3, 0x99, 0xb7, 0xc6, 0xff, 0x93, 0x85, 0x48, 0x2e, 0x33,
+	0x1f, 0xf3, 0xfa, 0x4f, 0x00, 0x00, 0x00, 0xff, 0xff, 0x97, 0x21, 0x44, 0x6d, 0xef, 0x03, 0x00,
 	0x00,
 }
 
diff --git a/protobuf/api/execution.proto b/protobuf/api/execution.proto
index d1a593f07..b9e1e6ecc 100644
--- a/protobuf/api/execution.proto
+++ b/protobuf/api/execution.proto
@@ -1,5 +1,6 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
 import "protobuf/types/execution.proto";
 
 package api;
@@ -29,7 +30,7 @@ service Execution {
 message CreateExecutionRequest {
   string instanceHash = 1;
   string taskKey = 2;
-  string inputs = 3;
+  google.protobuf.Struct inputs = 3;
   repeated string tags = 4;
 }
 
@@ -74,7 +75,7 @@ message UpdateExecutionRequest {
   // result pass to execution
   oneof result {
     // outputs is a success result.
-    string outputs = 2;
+    google.protobuf.Struct outputs = 2;
 
     // error is an error result.
     string error = 3;
diff --git a/protobuf/convert/pbstruct.go b/protobuf/convert/pbstruct.go
new file mode 100644
index 000000000..f06e6e395
--- /dev/null
+++ b/protobuf/convert/pbstruct.go
@@ -0,0 +1,44 @@
+package convert
+
+import (
+	"bytes"
+	"encoding/json"
+	"sync"
+
+	"github.com/golang/protobuf/jsonpb"
+	"github.com/golang/protobuf/proto"
+)
+
+var marshaler = jsonpb.Marshaler{EmitDefaults: true}
+
+var bufPool = sync.Pool{
+	New: func() interface{} {
+		return &bytes.Buffer{}
+	},
+}
+
+// Marshal converts protobuf struct to map[string]interface{}.
+func Marshal(in proto.Message, out interface{}) error {
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer bufPool.Put(buf)
+
+	dec := json.NewDecoder(buf)
+	if err := marshaler.Marshal(buf, in); err != nil {
+		return err
+	}
+	return dec.Decode(out)
+}
+
+// Unmarshal converts map[string]interface{} to protobuf struct.
+func Unmarshal(in interface{}, out proto.Message) error {
+	buf := bufPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer bufPool.Put(buf)
+
+	enc := json.NewEncoder(buf)
+	if err := enc.Encode(in); err != nil {
+		return err
+	}
+	return jsonpb.Unmarshal(buf, out)
+}
diff --git a/protobuf/types/event.pb.go b/protobuf/types/event.pb.go
index 6224f5220..14a172128 100644
--- a/protobuf/types/event.pb.go
+++ b/protobuf/types/event.pb.go
@@ -6,6 +6,7 @@ package types
 import (
 	fmt "fmt"
 	proto "github.com/golang/protobuf/proto"
+	_struct "github.com/golang/protobuf/ptypes/struct"
 	math "math"
 )
 
@@ -29,10 +30,10 @@ type Event struct {
 	// key is the key of the event.
 	Key string `protobuf:"bytes,3,opt,name=key,proto3" json:"key,omitempty"`
 	// data is the data for the event.
-	Data                 string   `protobuf:"bytes,4,opt,name=data,proto3" json:"data,omitempty"`
-	XXX_NoUnkeyedLiteral struct{} `json:"-"`
-	XXX_unrecognized     []byte   `json:"-"`
-	XXX_sizecache        int32    `json:"-"`
+	Data                 *_struct.Struct `protobuf:"bytes,4,opt,name=data,proto3" json:"data,omitempty"`
+	XXX_NoUnkeyedLiteral struct{}        `json:"-"`
+	XXX_unrecognized     []byte          `json:"-"`
+	XXX_sizecache        int32           `json:"-"`
 }
 
 func (m *Event) Reset()         { *m = Event{} }
@@ -81,11 +82,11 @@ func (m *Event) GetKey() string {
 	return ""
 }
 
-func (m *Event) GetData() string {
+func (m *Event) GetData() *_struct.Struct {
 	if m != nil {
 		return m.Data
 	}
-	return ""
+	return nil
 }
 
 func init() {
@@ -95,16 +96,18 @@ func init() {
 func init() { proto.RegisterFile("protobuf/types/event.proto", fileDescriptor_118d36ccf50c3798) }
 
 var fileDescriptor_118d36ccf50c3798 = []byte{
-	// 165 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x54, 0x8e, 0x31, 0x0b, 0xc2, 0x30,
-	0x10, 0x46, 0xa9, 0x6d, 0x05, 0x83, 0x83, 0x64, 0x2a, 0x4e, 0xd2, 0xc9, 0xc5, 0x46, 0xf4, 0x1f,
-	0x08, 0x82, 0xb3, 0xa3, 0x5b, 0xda, 0x5e, 0x93, 0x20, 0xbd, 0x14, 0x73, 0x11, 0xfa, 0xef, 0x25,
-	0xe7, 0xd4, 0xed, 0xdd, 0x7b, 0xf0, 0x71, 0x62, 0x3f, 0x7d, 0x3c, 0xf9, 0x36, 0x0e, 0x8a, 0xe6,
-	0x09, 0x82, 0x82, 0x2f, 0x20, 0x35, 0x2c, 0x65, 0xc9, 0xaa, 0x06, 0x51, 0xde, 0x93, 0x95, 0x52,
-	0x14, 0x56, 0x07, 0x5b, 0x65, 0x87, 0xec, 0xb8, 0x79, 0x32, 0xcb, 0x5a, 0x6c, 0x1d, 0x06, 0xd2,
-	0xd8, 0xc1, 0x23, 0xb5, 0x15, 0xb7, 0x85, 0x93, 0x3b, 0x91, 0xbf, 0x61, 0xae, 0x72, 0x4e, 0x09,
-	0xd3, 0x52, 0xaf, 0x49, 0x57, 0xc5, 0x7f, 0x29, 0xf1, 0xed, 0xf2, 0x3a, 0x1b, 0x47, 0x36, 0xb6,
-	0x4d, 0xe7, 0x47, 0x35, 0x42, 0x30, 0xa7, 0xc1, 0x47, 0xec, 0x35, 0x39, 0x8f, 0x0a, 0xd0, 0x38,
-	0x04, 0xb5, 0xfc, 0xb6, 0x5d, 0xf3, 0x7d, 0xfd, 0x05, 0x00, 0x00, 0xff, 0xff, 0x90, 0xf8, 0x6a,
-	0x46, 0xc6, 0x00, 0x00, 0x00,
+	// 202 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x92, 0x2a, 0x28, 0xca, 0x2f,
+	0xc9, 0x4f, 0x2a, 0x4d, 0xd3, 0x2f, 0xa9, 0x2c, 0x48, 0x2d, 0xd6, 0x4f, 0x2d, 0x4b, 0xcd, 0x2b,
+	0xd1, 0x03, 0x0b, 0x0a, 0xb1, 0x82, 0x85, 0xa4, 0x64, 0xd2, 0xf3, 0xf3, 0xd3, 0x73, 0x52, 0xf5,
+	0xe1, 0x2a, 0x8b, 0x4b, 0x8a, 0x4a, 0x93, 0xa1, 0x8a, 0x94, 0xea, 0xb8, 0x58, 0x5d, 0x41, 0x7a,
+	0x84, 0x84, 0xb8, 0x58, 0x32, 0x12, 0x8b, 0x33, 0x24, 0x18, 0x15, 0x18, 0x35, 0x38, 0x83, 0xc0,
+	0x6c, 0x21, 0x25, 0x2e, 0x9e, 0xcc, 0xbc, 0xe2, 0x92, 0xc4, 0xbc, 0xe4, 0x54, 0x0f, 0x90, 0x1c,
+	0x13, 0x58, 0x0e, 0x45, 0x4c, 0x48, 0x80, 0x8b, 0x39, 0x3b, 0xb5, 0x52, 0x82, 0x19, 0x2c, 0x05,
+	0x62, 0x0a, 0x69, 0x73, 0xb1, 0xa4, 0x24, 0x96, 0x24, 0x4a, 0xb0, 0x28, 0x30, 0x6a, 0x70, 0x1b,
+	0x89, 0xeb, 0x41, 0xec, 0xd7, 0x83, 0xd9, 0xaf, 0x17, 0x0c, 0xb6, 0x3f, 0x08, 0xac, 0xc8, 0xc9,
+	0x28, 0xca, 0x20, 0x3d, 0xb3, 0x24, 0xa3, 0x34, 0x49, 0x2f, 0x39, 0x3f, 0x57, 0x3f, 0x37, 0xb5,
+	0x38, 0x5d, 0x37, 0x2d, 0xbf, 0x34, 0x2f, 0x25, 0xb1, 0x24, 0x33, 0x3f, 0x4f, 0x3f, 0x35, 0x2f,
+	0x3d, 0x33, 0x0f, 0xc9, 0xe9, 0x60, 0x1f, 0x25, 0xb1, 0x81, 0xf9, 0xc6, 0x80, 0x00, 0x00, 0x00,
+	0xff, 0xff, 0xb4, 0x6b, 0x0b, 0x88, 0xfd, 0x00, 0x00, 0x00,
 }
diff --git a/protobuf/types/event.proto b/protobuf/types/event.proto
index 882393b0b..d93ef0adf 100644
--- a/protobuf/types/event.proto
+++ b/protobuf/types/event.proto
@@ -1,5 +1,7 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
+
 package types;
 option go_package = "github.com/mesg-foundation/engine/protobuf/types";
 
@@ -15,5 +17,5 @@ message Event {
   string key = 3;
 
   // data is the data for the event.
-  string data = 4;
+  google.protobuf.Struct data = 4;
 }
diff --git a/protobuf/types/execution.pb.go b/protobuf/types/execution.pb.go
index e55018042..942596fe7 100644
--- a/protobuf/types/execution.pb.go
+++ b/protobuf/types/execution.pb.go
@@ -6,6 +6,7 @@ package types
 import (
 	fmt "fmt"
 	proto "github.com/golang/protobuf/proto"
+	_struct "github.com/golang/protobuf/ptypes/struct"
 	math "math"
 )
 
@@ -77,9 +78,9 @@ type Execution struct {
 	// taskKey is the key of the task of this execution.
 	TaskKey string `protobuf:"bytes,6,opt,name=taskKey,proto3" json:"taskKey,omitempty"`
 	// inputs data of the execution.
-	Inputs string `protobuf:"bytes,7,opt,name=inputs,proto3" json:"inputs,omitempty"`
+	Inputs *_struct.Struct `protobuf:"bytes,7,opt,name=inputs,proto3" json:"inputs,omitempty"`
 	// outputs are the returned data of successful execution.
-	Outputs string `protobuf:"bytes,8,opt,name=outputs,proto3" json:"outputs,omitempty"`
+	Outputs *_struct.Struct `protobuf:"bytes,8,opt,name=outputs,proto3" json:"outputs,omitempty"`
 	// error message of a failed execution.
 	Error string `protobuf:"bytes,9,opt,name=error,proto3" json:"error,omitempty"`
 	// tags are optionally associated with execution by the user.
@@ -156,18 +157,18 @@ func (m *Execution) GetTaskKey() string {
 	return ""
 }
 
-func (m *Execution) GetInputs() string {
+func (m *Execution) GetInputs() *_struct.Struct {
 	if m != nil {
 		return m.Inputs
 	}
-	return ""
+	return nil
 }
 
-func (m *Execution) GetOutputs() string {
+func (m *Execution) GetOutputs() *_struct.Struct {
 	if m != nil {
 		return m.Outputs
 	}
-	return ""
+	return nil
 }
 
 func (m *Execution) GetError() string {
@@ -192,25 +193,27 @@ func init() {
 func init() { proto.RegisterFile("protobuf/types/execution.proto", fileDescriptor_42e00237fcad5e7f) }
 
 var fileDescriptor_42e00237fcad5e7f = []byte{
-	// 315 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x54, 0x91, 0x6d, 0x4b, 0x02, 0x41,
-	0x10, 0xc7, 0x3b, 0x1f, 0xce, 0x6e, 0x4a, 0x39, 0x86, 0x88, 0x7d, 0x11, 0x22, 0x42, 0x20, 0x41,
-	0x77, 0x61, 0xdf, 0x20, 0x29, 0x8a, 0x08, 0xc2, 0xe8, 0x4d, 0xef, 0x56, 0x1d, 0xcf, 0x43, 0xdd,
-	0x3d, 0xf6, 0xa1, 0xf2, 0xcb, 0xf4, 0x59, 0x63, 0x47, 0xa5, 0x7c, 0x37, 0xff, 0xdf, 0x8f, 0x99,
-	0xdd, 0xd9, 0x85, 0x6e, 0x65, 0xb4, 0xd3, 0x13, 0x3f, 0xcf, 0xdd, 0xa6, 0x22, 0x9b, 0xd3, 0x37,
-	0x4d, 0xbd, 0x2b, 0xb5, 0xca, 0x58, 0x60, 0x93, 0x71, 0xff, 0xa7, 0x06, 0xc9, 0xfd, 0x5e, 0x21,
-	0x42, 0x63, 0x21, 0xed, 0x42, 0x44, 0xbd, 0x68, 0x90, 0x8c, 0xb9, 0xc6, 0x2e, 0x40, 0x25, 0x0d,
-	0x29, 0xf7, 0x18, 0x4c, 0x8d, 0xcd, 0x3f, 0x82, 0x17, 0x90, 0xd0, 0xe7, 0x5e, 0xd7, 0x59, 0xff,
-	0x01, 0xbc, 0x84, 0xd8, 0x3a, 0xe9, 0xbc, 0x15, 0x8d, 0x5e, 0x34, 0xe8, 0x0c, 0xdb, 0x19, 0x9f,
-	0x9b, 0xbd, 0x31, 0x1c, 0xef, 0x24, 0xf6, 0xe1, 0xb4, 0x54, 0xd6, 0x49, 0x35, 0x25, 0x9e, 0xd3,
-	0xe4, 0x39, 0x07, 0x0c, 0x05, 0xb4, 0x9c, 0xb4, 0xcb, 0x67, 0xda, 0x88, 0x98, 0xf5, 0x3e, 0xe2,
-	0x39, 0xc4, 0xa5, 0xaa, 0xbc, 0xb3, 0xa2, 0xc5, 0x62, 0x97, 0x42, 0x87, 0xf6, 0x8e, 0xc5, 0xf1,
-	0xb6, 0x63, 0x17, 0xf1, 0x0c, 0x9a, 0x64, 0x8c, 0x36, 0x22, 0x61, 0xbe, 0x0d, 0x61, 0x7d, 0x27,
-	0x0b, 0x2b, 0xa0, 0x57, 0x0f, 0xeb, 0x87, 0xfa, 0xea, 0x05, 0xe2, 0xed, 0x5d, 0xf1, 0x04, 0x5a,
-	0xef, 0x6a, 0xa9, 0xf4, 0x97, 0x4a, 0x8f, 0x42, 0x18, 0x19, 0x92, 0x8e, 0x66, 0x69, 0x84, 0x1d,
-	0x80, 0x27, 0xf5, 0x6a, 0x74, 0x61, 0xc8, 0xda, 0xb4, 0x86, 0x6d, 0x48, 0x46, 0x7a, 0x5d, 0xad,
-	0x28, 0xe8, 0x3a, 0x02, 0xc4, 0x0f, 0xb2, 0x5c, 0xd1, 0x2c, 0x6d, 0xdc, 0x0d, 0x3f, 0x6e, 0x8a,
-	0xd2, 0x2d, 0xfc, 0x24, 0x9b, 0xea, 0x75, 0xbe, 0x26, 0x5b, 0x5c, 0xcf, 0xb5, 0x57, 0x33, 0x19,
-	0xde, 0x3f, 0x27, 0x55, 0x94, 0x8a, 0xf2, 0xc3, 0xaf, 0x9b, 0xc4, 0x9c, 0x6f, 0x7f, 0x03, 0x00,
-	0x00, 0xff, 0xff, 0x7e, 0xb5, 0xfe, 0x7d, 0xd3, 0x01, 0x00, 0x00,
+	// 352 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x7c, 0x91, 0xdd, 0x4a, 0xfb, 0x40,
+	0x10, 0xc5, 0xff, 0xe9, 0x47, 0xf2, 0xcf, 0xd4, 0x96, 0xb0, 0x08, 0x06, 0x29, 0x25, 0x14, 0x84,
+	0x22, 0x98, 0x68, 0x7d, 0x03, 0x8b, 0xa2, 0x88, 0x20, 0x2d, 0xde, 0x78, 0xb7, 0x4d, 0xa7, 0x69,
+	0x68, 0xbb, 0x1b, 0xf6, 0x43, 0xed, 0x5b, 0xfa, 0x48, 0x92, 0x49, 0xa3, 0xf5, 0xc6, 0xbb, 0x3d,
+	0xe7, 0x77, 0x66, 0x93, 0x33, 0x0b, 0x83, 0x42, 0x49, 0x23, 0xe7, 0x76, 0x99, 0x98, 0x5d, 0x81,
+	0x3a, 0xc1, 0x0f, 0x4c, 0xad, 0xc9, 0xa5, 0x88, 0x09, 0xb0, 0x36, 0xd9, 0xa7, 0xfd, 0x4c, 0xca,
+	0x6c, 0x83, 0xc9, 0x77, 0x5a, 0x1b, 0x65, 0x53, 0x53, 0x85, 0x86, 0x9f, 0x0d, 0xf0, 0x6f, 0xeb,
+	0x41, 0xc6, 0xa0, 0xb5, 0xe2, 0x7a, 0x15, 0x3a, 0x91, 0x33, 0xf2, 0xa7, 0x74, 0x66, 0x03, 0x80,
+	0x82, 0x2b, 0x14, 0xe6, 0xbe, 0x24, 0x0d, 0x22, 0x07, 0x0e, 0xeb, 0x83, 0x8f, 0x6f, 0x35, 0x6e,
+	0x12, 0xfe, 0x31, 0xd8, 0x19, 0xb8, 0xda, 0x70, 0x63, 0x75, 0xd8, 0x8a, 0x9c, 0x51, 0x6f, 0xdc,
+	0x8d, 0xe9, 0xaf, 0xe2, 0x19, 0x99, 0xd3, 0x3d, 0x64, 0x43, 0x38, 0xca, 0x85, 0x36, 0x5c, 0xa4,
+	0x48, 0xf7, 0xb4, 0xe9, 0x9e, 0x5f, 0x1e, 0x0b, 0xc1, 0x33, 0x5c, 0xaf, 0x1f, 0x71, 0x17, 0xba,
+	0x84, 0x6b, 0xc9, 0x12, 0x70, 0x73, 0x51, 0x58, 0xa3, 0x43, 0x2f, 0x72, 0x46, 0x9d, 0xf1, 0x49,
+	0x5c, 0x75, 0x8e, 0xeb, 0xce, 0xf1, 0x8c, 0x3a, 0x4f, 0xf7, 0x31, 0x76, 0x05, 0x9e, 0xb4, 0x86,
+	0x26, 0xfe, 0xff, 0x3d, 0x51, 0xe7, 0xd8, 0x31, 0xb4, 0x51, 0x29, 0xa9, 0x42, 0x9f, 0xbe, 0x5d,
+	0x89, 0x72, 0x61, 0x86, 0x67, 0x3a, 0x84, 0xa8, 0x59, 0x2e, 0xac, 0x3c, 0x9f, 0x3f, 0x81, 0x5b,
+	0xb5, 0x63, 0x1d, 0xf0, 0x5e, 0xc4, 0x5a, 0xc8, 0x77, 0x11, 0xfc, 0x2b, 0xc5, 0x44, 0x21, 0x37,
+	0xb8, 0x08, 0x1c, 0xd6, 0x03, 0x78, 0x10, 0xcf, 0x4a, 0x66, 0x0a, 0xb5, 0x0e, 0x1a, 0xac, 0x0b,
+	0xfe, 0x44, 0x6e, 0x8b, 0x0d, 0x96, 0xb8, 0xc9, 0x00, 0xdc, 0x3b, 0x9e, 0x6f, 0x70, 0x11, 0xb4,
+	0x6e, 0xc6, 0xaf, 0x97, 0x59, 0x6e, 0x56, 0x76, 0x1e, 0xa7, 0x72, 0x9b, 0x6c, 0x51, 0x67, 0x17,
+	0x4b, 0x69, 0xc5, 0x82, 0x97, 0x2f, 0x96, 0xa0, 0xc8, 0x72, 0x71, 0xf0, 0xb8, 0xb4, 0xdd, 0xb9,
+	0x4b, 0xfa, 0xfa, 0x2b, 0x00, 0x00, 0xff, 0xff, 0x9b, 0xe4, 0x91, 0x77, 0x23, 0x02, 0x00, 0x00,
 }
diff --git a/protobuf/types/execution.proto b/protobuf/types/execution.proto
index e06934a5d..a0fe00f57 100644
--- a/protobuf/types/execution.proto
+++ b/protobuf/types/execution.proto
@@ -1,5 +1,7 @@
 syntax = "proto3";
 
+import "google/protobuf/struct.proto";
+
 package types;
 option go_package = "github.com/mesg-foundation/engine/protobuf/types";
 
@@ -44,10 +46,10 @@ message Execution {
   string taskKey = 6;
 
   // inputs data of the execution.
-  string inputs = 7;
+  google.protobuf.Struct inputs = 7;
 
   // outputs are the returned data of successful execution.
-  string outputs = 8;
+  google.protobuf.Struct outputs = 8;
 
   // error message of a failed execution.
   string error = 9;
diff --git a/sdk/execution/execution.go b/sdk/execution/execution.go
index b7d1156bf..62c68f2be 100644
--- a/sdk/execution/execution.go
+++ b/sdk/execution/execution.go
@@ -1,7 +1,6 @@
 package executionsdk
 
 import (
-	"encoding/json"
 	"fmt"
 
 	"github.com/cskr/pubsub"
@@ -49,7 +48,7 @@ func (e *Execution) GetStream(f *Filter) *Listener {
 }
 
 // Update updates execution that matches given hash.
-func (e *Execution) Update(executionHash hash.Hash, outputs []byte, reterr error) error {
+func (e *Execution) Update(executionHash hash.Hash, outputs map[string]interface{}, reterr error) error {
 	exec, err := e.processExecution(executionHash, outputs, reterr)
 	if err != nil {
 		return err
@@ -61,7 +60,7 @@ func (e *Execution) Update(executionHash hash.Hash, outputs []byte, reterr error
 }
 
 // processExecution processes execution and marks it as complated or failed.
-func (e *Execution) processExecution(executionHash hash.Hash, outputData []byte, reterr error) (*execution.Execution, error) {
+func (e *Execution) processExecution(executionHash hash.Hash, outputs map[string]interface{}, reterr error) (*execution.Execution, error) {
 	tx, err := e.execDB.OpenTransaction()
 	if err != nil {
 		return nil, err
@@ -79,13 +78,13 @@ func (e *Execution) processExecution(executionHash hash.Hash, outputData []byte,
 			return nil, err
 		}
 	} else {
-		o, err := e.validateExecutionOutput(exec.InstanceHash, exec.TaskKey, outputData)
+		err := e.validateExecutionOutput(exec.InstanceHash, exec.TaskKey, outputs)
 		if err != nil {
 			if err1 := exec.Failed(err); err1 != nil {
 				tx.Discard()
 				return nil, err1
 			}
-		} else if err := exec.Complete(o); err != nil {
+		} else if err := exec.Complete(outputs); err != nil {
 			tx.Discard()
 			return nil, err
 		}
@@ -104,26 +103,18 @@ func (e *Execution) processExecution(executionHash hash.Hash, outputData []byte,
 	return exec, nil
 }
 
-func (e *Execution) validateExecutionOutput(instanceHash hash.Hash, taskKey string, jsonout []byte) (map[string]interface{}, error) {
-	var output map[string]interface{}
-	if err := json.Unmarshal(jsonout, &output); err != nil {
-		return nil, fmt.Errorf("invalid output: %s", err)
-	}
-
+func (e *Execution) validateExecutionOutput(instanceHash hash.Hash, taskKey string, outputs map[string]interface{}) error {
 	i, err := e.instance.Get(instanceHash)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
 	s, err := e.service.Get(i.ServiceHash)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
-	if err := s.RequireTaskOutputs(taskKey, output); err != nil {
-		return nil, err
-	}
-	return output, nil
+	return s.RequireTaskOutputs(taskKey, outputs)
 }
 
 // Execute executes a task tasKey with inputData and tags for service serviceID.
diff --git a/server/grpc/api/event.go b/server/grpc/api/event.go
index 0af0c200a..1f45cef46 100644
--- a/server/grpc/api/event.go
+++ b/server/grpc/api/event.go
@@ -2,14 +2,15 @@ package api
 
 import (
 	"context"
-	"encoding/json"
 	"errors"
 	"fmt"
 
+	structpb "github.com/golang/protobuf/ptypes/struct"
 	"github.com/mesg-foundation/engine/event"
 	"github.com/mesg-foundation/engine/hash"
 	"github.com/mesg-foundation/engine/protobuf/acknowledgement"
 	"github.com/mesg-foundation/engine/protobuf/api"
+	"github.com/mesg-foundation/engine/protobuf/convert"
 	"github.com/mesg-foundation/engine/protobuf/types"
 	"github.com/mesg-foundation/engine/sdk"
 	eventsdk "github.com/mesg-foundation/engine/sdk/event"
@@ -36,10 +37,11 @@ func (s *EventServer) Create(ctx context.Context, req *api.CreateEventRequest) (
 		return nil, errors.New("create event: key missing")
 	}
 
-	var data map[string]interface{}
-	if err := json.Unmarshal([]byte(req.Data), &data); err != nil {
-		return nil, fmt.Errorf("create event: data %s", err)
+	data := make(map[string]interface{})
+	if err := convert.Marshal(req.Data, &data); err != nil {
+		return nil, err
 	}
+
 	event, err := s.sdk.Event.Create(instanceHash, req.Key, data)
 	if err != nil {
 		return nil, fmt.Errorf("create event: data %s", err)
@@ -74,13 +76,13 @@ func (s *EventServer) Stream(req *api.StreamEventRequest, resp api.Event_StreamS
 		return err
 	}
 
-	for exec := range stream.C {
-		pexec, err := toProtoEvent(exec)
+	for event := range stream.C {
+		e, err := toProtoEvent(event)
 		if err != nil {
 			return err
 		}
 
-		if err := resp.Send(pexec); err != nil {
+		if err := resp.Send(e); err != nil {
 			return err
 		}
 	}
@@ -89,8 +91,8 @@ func (s *EventServer) Stream(req *api.StreamEventRequest, resp api.Event_StreamS
 }
 
 func toProtoEvent(e *event.Event) (*types.Event, error) {
-	data, err := json.Marshal(e.Data)
-	if err != nil {
+	data := &structpb.Struct{}
+	if err := convert.Unmarshal(e.Data, data); err != nil {
 		return nil, err
 	}
 
@@ -98,6 +100,6 @@ func toProtoEvent(e *event.Event) (*types.Event, error) {
 		Hash:         e.Hash.String(),
 		InstanceHash: e.InstanceHash.String(),
 		Key:          e.Key,
-		Data:         string(data),
+		Data:         data,
 	}, nil
 }
diff --git a/server/grpc/api/execution.go b/server/grpc/api/execution.go
index 4616ca420..ffd5a3027 100644
--- a/server/grpc/api/execution.go
+++ b/server/grpc/api/execution.go
@@ -2,14 +2,14 @@ package api
 
 import (
 	"context"
-	"encoding/json"
 	"errors"
-	"fmt"
 
+	structpb "github.com/golang/protobuf/ptypes/struct"
 	"github.com/mesg-foundation/engine/execution"
 	"github.com/mesg-foundation/engine/hash"
 	"github.com/mesg-foundation/engine/protobuf/acknowledgement"
 	"github.com/mesg-foundation/engine/protobuf/api"
+	"github.com/mesg-foundation/engine/protobuf/convert"
 	"github.com/mesg-foundation/engine/protobuf/types"
 	"github.com/mesg-foundation/engine/sdk"
 	executionsdk "github.com/mesg-foundation/engine/sdk/execution"
@@ -35,11 +35,10 @@ func (s *ExecutionServer) Create(ctx context.Context, req *api.CreateExecutionRe
 		return nil, err
 	}
 
-	var inputs map[string]interface{}
-	if err := json.Unmarshal([]byte(req.Inputs), &inputs); err != nil {
-		return nil, fmt.Errorf("cannot parse execution's inputs (JSON format): %s", err)
+	inputs := make(map[string]interface{})
+	if err := convert.Marshal(req.Inputs, &inputs); err != nil {
+		return nil, err
 	}
-
 	eventHash, err := hash.Random()
 	if err != nil {
 		return nil, err
@@ -100,12 +99,12 @@ func (s *ExecutionServer) Stream(req *api.StreamExecutionRequest, resp api.Execu
 	}
 
 	for exec := range stream.C {
-		pexec, err := toProtoExecution(exec)
+		e, err := toProtoExecution(exec)
 		if err != nil {
 			return err
 		}
 
-		if err := resp.Send(pexec); err != nil {
+		if err := resp.Send(e); err != nil {
 			return err
 		}
 	}
@@ -121,7 +120,12 @@ func (s *ExecutionServer) Update(ctx context.Context, req *api.UpdateExecutionRe
 	}
 	switch res := req.Result.(type) {
 	case *api.UpdateExecutionRequest_Outputs:
-		err = s.sdk.Execution.Update(hash, []byte(res.Outputs), nil)
+		outputs := make(map[string]interface{})
+		if err := convert.Marshal(res.Outputs, &outputs); err != nil {
+			return nil, err
+		}
+
+		err = s.sdk.Execution.Update(hash, outputs, nil)
 	case *api.UpdateExecutionRequest_Error:
 		err = s.sdk.Execution.Update(hash, nil, errors.New(res.Error))
 	default:
@@ -136,13 +140,13 @@ func (s *ExecutionServer) Update(ctx context.Context, req *api.UpdateExecutionRe
 }
 
 func toProtoExecution(exec *execution.Execution) (*types.Execution, error) {
-	inputs, err := json.Marshal(exec.Inputs)
-	if err != nil {
+	inputs := &structpb.Struct{}
+	if err := convert.Unmarshal(exec.Inputs, inputs); err != nil {
 		return nil, err
 	}
 
-	outputs, err := json.Marshal(exec.Outputs)
-	if err != nil {
+	outputs := &structpb.Struct{}
+	if err := convert.Unmarshal(exec.Outputs, outputs); err != nil {
 		return nil, err
 	}
 
@@ -153,8 +157,8 @@ func toProtoExecution(exec *execution.Execution) (*types.Execution, error) {
 		Status:       types.Status(exec.Status),
 		InstanceHash: exec.InstanceHash.String(),
 		TaskKey:      exec.TaskKey,
-		Inputs:       string(inputs),
-		Outputs:      string(outputs),
+		Inputs:       inputs,
+		Outputs:      outputs,
 		Tags:         exec.Tags,
 		Error:        exec.Error,
 	}, nil
diff --git a/systemservices/ethwallet/client/encoding.go b/systemservices/ethwallet/client/encoding.go
index 54a43cdb7..b09efe1f0 100644
--- a/systemservices/ethwallet/client/encoding.go
+++ b/systemservices/ethwallet/client/encoding.go
@@ -1,13 +1,30 @@
 package client
 
-import "encoding/json"
+import (
+	"encoding/json"
+)
 
 // Marshal returns the MESG format encoding of v.
-func Marshal(v interface{}) ([]byte, error) {
-	return json.Marshal(v)
+func Marshal(input interface{}) (map[string]interface{}, error) {
+	b, err := json.Marshal(input)
+	if err != nil {
+		return nil, err
+	}
+
+	var output map[string]interface{}
+	if err := json.Unmarshal(b, &output); err != nil {
+		return nil, err
+	}
+
+	return output, nil
 }
 
 // Unmarshal parses the MESG-encoded data input and stores the result in the value pointed to by v.
-func Unmarshal(input []byte, v interface{}) error {
-	return json.Unmarshal(input, v)
+func Unmarshal(input map[string]interface{}, output interface{}) error {
+	b, err := json.Marshal(input)
+	if err != nil {
+		return err
+	}
+
+	return json.Unmarshal(b, output)
 }
diff --git a/systemservices/ethwallet/client/task_runner.go b/systemservices/ethwallet/client/task_runner.go
index 392094910..036ed703b 100644
--- a/systemservices/ethwallet/client/task_runner.go
+++ b/systemservices/ethwallet/client/task_runner.go
@@ -2,13 +2,16 @@ package client
 
 import (
 	"context"
+	"fmt"
 
+	structpb "github.com/golang/protobuf/ptypes/struct"
 	pb "github.com/mesg-foundation/engine/protobuf/api"
+	"github.com/mesg-foundation/engine/protobuf/convert"
 	"github.com/mesg-foundation/engine/protobuf/types"
 )
 
 // TaskFn is a task function handler prototype.
-type TaskFn func(inputs []byte) ([]byte, error)
+type TaskFn func(inputs map[string]interface{}) (map[string]interface{}, error)
 
 // TaskRunner handles running task in a loop.
 type TaskRunner struct {
@@ -40,17 +43,27 @@ func (r *TaskRunner) Run() error {
 		}
 
 		if _, ok := r.defs[exec.TaskKey]; !ok {
+			return fmt.Errorf("servic has no %s task", exec.TaskKey)
+		}
+
+		inputs := make(map[string]interface{})
+		if err := convert.Marshal(exec.Inputs, &inputs); err != nil {
 			return err
 		}
 
-		output, err := r.defs[exec.TaskKey]([]byte(exec.Inputs))
+		output, err := r.defs[exec.TaskKey](inputs)
 		req := &pb.UpdateExecutionRequest{
 			Hash: exec.Hash,
-			Result: &pb.UpdateExecutionRequest_Outputs{
-				Outputs: string(output),
-			},
 		}
-		if err != nil {
+		if err == nil {
+			outputs := &structpb.Struct{}
+			if err := convert.Unmarshal(output, outputs); err != nil {
+				return err
+			}
+			req.Result = &pb.UpdateExecutionRequest_Outputs{
+				Outputs: outputs,
+			}
+		} else {
 			req.Result = &pb.UpdateExecutionRequest_Error{
 				Error: err.Error(),
 			}
diff --git a/systemservices/ethwallet/compiled.json b/systemservices/ethwallet/compiled.json
index a07ea1b4e..7e65ae1e8 100644
--- a/systemservices/ethwallet/compiled.json
+++ b/systemservices/ethwallet/compiled.json
@@ -1 +1 @@
-{"sid":"ethwallet","name":"Ethereum Wallet","description":"Manage Ethereum accounts and sign transactions.","tasks":[{"key":"list","name":"List accounts","description":"Return the addresses of existing account.","inputs":[],"outputs":[{"key":"addresses","name":"Addresses","description":"List of addresses.","type":"String","repeated":true,"object":[]}]},{"key":"create","name":"Create a new account","description":"Create a new account with a passphrase. Make sure to backup the passphrase.","inputs":[{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"delete","name":"Delete an account","description":"Delete an account from the wallet. Need the address and its associated passphrase.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"export","name":"Export an account","description":"Export an existing account in order to backup it and import it in an other wallet. Respect the Web3 Secret Storage specification. See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"id","name":"ID","description":"The id of the account.","type":"String","object":[]},{"key":"version","name":"Version","description":"The version used to export the account.","type":"Number","object":[]},{"key":"crypto","name":"Crypto","description":"The encrypted account.","type":"Object","object":[]}]},{"key":"import","name":"Import an account","description":"Import an account. The account have to respect the Web3 Secret Storage specification. See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.","inputs":[{"key":"account","name":"Account","description":"The JSON encoded account.","type":"Object","object":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"id","name":"ID","description":"The id of the account.","type":"String","object":[]},{"key":"version","name":"Version","description":"The version used to export the account.","type":"Number","object":[]},{"key":"crypto","name":"Crypto","description":"The encrypted account.","type":"Object","object":[]}]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"sign","name":"Sign transaction","description":"Sign a transaction with the specified account.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]},{"key":"transaction","name":"Transaction","description":"The transaction to sign.","type":"Object","object":[{"key":"chainID","name":"Chain ID","description":"The ID of the chain the transaction is for. See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-155.md#list-of-chain-ids.","type":"Number","object":[]},{"key":"nonce","name":"Nonce","description":"Nonce to use.","type":"Number","object":[]},{"key":"to","name":"To","description":"The to address.","type":"String","object":[]},{"key":"value","name":"Value","description":"The value in Wei.","type":"String","object":[]},{"key":"gas","name":"Gas","description":"The maximum gas to use to execute this transaction","type":"Number","object":[]},{"key":"gasPrice","name":"Gas price","description":"The gas price in Wei.","type":"String","object":[]},{"key":"data","name":"Data","description":"The data of the transaction.","type":"String","object":[]}]}],"outputs":[{"key":"signedTransaction","name":"Signed transaction","description":"The signed transaction.","type":"String","object":[]}]},{"key":"importFromPrivateKey","name":"Import an account from a private key","description":"Import an account from a private key.","inputs":[{"key":"privateKey","name":"Private key","description":"The private key to import.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]}],"events":[],"dependencies":[],"configuration":{"env":["MESG_KEYSTORE=/keystore"],"volumes":["/keystore"]},"source":"QmQvFGZiTN2yEUMgBq6bjcrLGL95jegjNdTd9zeYf6gzke"}
+{"sid":"ethwallet","name":"Ethereum Wallet","description":"Manage Ethereum accounts and sign transactions.","tasks":[{"key":"list","name":"List accounts","description":"Return the addresses of existing account.","inputs":[],"outputs":[{"key":"addresses","name":"Addresses","description":"List of addresses.","type":"String","repeated":true,"object":[]}]},{"key":"create","name":"Create a new account","description":"Create a new account with a passphrase. Make sure to backup the passphrase.","inputs":[{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"delete","name":"Delete an account","description":"Delete an account from the wallet. Need the address and its associated passphrase.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"export","name":"Export an account","description":"Export an existing account in order to backup it and import it in an other wallet. Respect the Web3 Secret Storage specification. See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"id","name":"ID","description":"The id of the account.","type":"String","object":[]},{"key":"version","name":"Version","description":"The version used to export the account.","type":"Number","object":[]},{"key":"crypto","name":"Crypto","description":"The encrypted account.","type":"Object","object":[]}]},{"key":"import","name":"Import an account","description":"Import an account. The account have to respect the Web3 Secret Storage specification. See https://github.com/ethereum/wiki/wiki/Web3-Secret-Storage-Definition for more information.","inputs":[{"key":"account","name":"Account","description":"The JSON encoded account.","type":"Object","object":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"id","name":"ID","description":"The id of the account.","type":"String","object":[]},{"key":"version","name":"Version","description":"The version used to export the account.","type":"Number","object":[]},{"key":"crypto","name":"Crypto","description":"The encrypted account.","type":"Object","object":[]}]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]},{"key":"sign","name":"Sign transaction","description":"Sign a transaction with the specified account.","inputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]},{"key":"transaction","name":"Transaction","description":"The transaction to sign.","type":"Object","object":[{"key":"chainID","name":"Chain ID","description":"The ID of the chain the transaction is for. See https://github.com/ethereum/EIPs/blob/master/EIPS/eip-155.md#list-of-chain-ids.","type":"Number","object":[]},{"key":"nonce","name":"Nonce","description":"Nonce to use.","type":"Number","object":[]},{"key":"to","name":"To","description":"The to address.","type":"String","object":[]},{"key":"value","name":"Value","description":"The value in Wei.","type":"String","object":[]},{"key":"gas","name":"Gas","description":"The maximum gas to use to execute this transaction","type":"Number","object":[]},{"key":"gasPrice","name":"Gas price","description":"The gas price in Wei.","type":"String","object":[]},{"key":"data","name":"Data","description":"The data of the transaction.","type":"String","object":[]}]}],"outputs":[{"key":"signedTransaction","name":"Signed transaction","description":"The signed transaction.","type":"String","object":[]}]},{"key":"importFromPrivateKey","name":"Import an account from a private key","description":"Import an account from a private key.","inputs":[{"key":"privateKey","name":"Private key","description":"The private key to import.","type":"String","object":[]},{"key":"passphrase","name":"Passphrase","description":"Passphrase to use with the account.","type":"String","object":[]}],"outputs":[{"key":"address","name":"Address","description":"The public address of the account.","type":"String","object":[]}]}],"events":[],"dependencies":[],"configuration":{"env":["MESG_KEYSTORE=/keystore"],"volumes":["/keystore"]},"source":"QmWJMCurpAQiAgSDW6dMpUH8Xktbvo4DyVd5jSrAQazDFG"}
diff --git a/systemservices/ethwallet/ethwallet/create.go b/systemservices/ethwallet/ethwallet/create.go
index d55bbf1b1..b6040d2e4 100644
--- a/systemservices/ethwallet/ethwallet/create.go
+++ b/systemservices/ethwallet/ethwallet/create.go
@@ -13,7 +13,7 @@ type createOutputSuccess struct {
 	Address common.Address `json:"address"`
 }
 
-func (s *Ethwallet) create(input []byte) ([]byte, error) {
+func (s *Ethwallet) create(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs createInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/ethwallet/delete.go b/systemservices/ethwallet/ethwallet/delete.go
index d8d862495..41198cdae 100644
--- a/systemservices/ethwallet/ethwallet/delete.go
+++ b/systemservices/ethwallet/ethwallet/delete.go
@@ -15,7 +15,7 @@ type deleteOutputSuccess struct {
 	Address common.Address `json:"address"`
 }
 
-func (s *Ethwallet) delete(input []byte) ([]byte, error) {
+func (s *Ethwallet) delete(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs deleteInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/ethwallet/export.go b/systemservices/ethwallet/ethwallet/export.go
index ddf526968..f3405a0ba 100644
--- a/systemservices/ethwallet/ethwallet/export.go
+++ b/systemservices/ethwallet/ethwallet/export.go
@@ -13,7 +13,7 @@ type exportInputs struct {
 	Passphrase string         `json:"passphrase"`
 }
 
-func (s *Ethwallet) export(input []byte) ([]byte, error) {
+func (s *Ethwallet) export(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs exportInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/ethwallet/import.go b/systemservices/ethwallet/ethwallet/import.go
index 9d2336c57..5c458413d 100644
--- a/systemservices/ethwallet/ethwallet/import.go
+++ b/systemservices/ethwallet/ethwallet/import.go
@@ -16,7 +16,7 @@ type importOutputSuccess struct {
 	Address common.Address `json:"address"`
 }
 
-func (s *Ethwallet) importA(input []byte) ([]byte, error) {
+func (s *Ethwallet) importA(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs importInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/ethwallet/importFromPrivateKey.go b/systemservices/ethwallet/ethwallet/importFromPrivateKey.go
index 039ff545e..0d65b06d9 100644
--- a/systemservices/ethwallet/ethwallet/importFromPrivateKey.go
+++ b/systemservices/ethwallet/ethwallet/importFromPrivateKey.go
@@ -17,7 +17,7 @@ type importFromPrivateKeyOutputSuccess struct {
 	Address common.Address `json:"address"`
 }
 
-func (s *Ethwallet) importFromPrivateKey(input []byte) ([]byte, error) {
+func (s *Ethwallet) importFromPrivateKey(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs importFromPrivateKeyInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/ethwallet/list.go b/systemservices/ethwallet/ethwallet/list.go
index 4ee3bd3c6..7e83092c7 100644
--- a/systemservices/ethwallet/ethwallet/list.go
+++ b/systemservices/ethwallet/ethwallet/list.go
@@ -9,7 +9,7 @@ type listOutputSuccess struct {
 	Addresses []common.Address `json:"addresses"`
 }
 
-func (s *Ethwallet) list(input []byte) ([]byte, error) {
+func (s *Ethwallet) list(input map[string]interface{}) (map[string]interface{}, error) {
 	addresses := make([]common.Address, 0)
 	for _, account := range s.keystore.Accounts() {
 		addresses = append(addresses, account.Address)
diff --git a/systemservices/ethwallet/ethwallet/sign.go b/systemservices/ethwallet/ethwallet/sign.go
index 4db7857d7..e8a86f17e 100644
--- a/systemservices/ethwallet/ethwallet/sign.go
+++ b/systemservices/ethwallet/ethwallet/sign.go
@@ -32,7 +32,7 @@ type signOutputSuccess struct {
 	SignedTransaction string `json:"signedTransaction"`
 }
 
-func (s *Ethwallet) sign(input []byte) ([]byte, error) {
+func (s *Ethwallet) sign(input map[string]interface{}) (map[string]interface{}, error) {
 	var inputs signInputs
 	if err := client.Unmarshal(input, &inputs); err != nil {
 		return nil, err
diff --git a/systemservices/ethwallet/go.mod b/systemservices/ethwallet/go.mod
index 23c7fd292..4c3cde734 100644
--- a/systemservices/ethwallet/go.mod
+++ b/systemservices/ethwallet/go.mod
@@ -5,10 +5,14 @@ go 1.12
 require (
 	github.com/allegro/bigcache v1.2.1 // indirect
 	github.com/aristanetworks/goarista v0.0.0-20190628180533-8e7d5b18fe7a // indirect
+	github.com/btcsuite/btcd v0.0.0-20190629003639-c26ffa870fd8 // indirect
+	github.com/cespare/cp v1.1.1 // indirect
 	github.com/deckarep/golang-set v1.7.1 // indirect
 	github.com/ethereum/go-ethereum v1.8.27
 	github.com/go-stack/stack v1.8.0 // indirect
-	github.com/mesg-foundation/engine v0.5.1-0.20190702155243-a2826b3949a7
+	github.com/golang/protobuf v1.3.1
+	github.com/mesg-foundation/engine v0.5.1-0.20190725113935-3e817175f412
+	github.com/mitchellh/mapstructure v1.1.2
 	github.com/pborman/uuid v1.2.0 // indirect
 	github.com/rjeczalik/notify v0.9.2 // indirect
 	github.com/stretchr/testify v1.3.0
diff --git a/systemservices/ethwallet/go.sum b/systemservices/ethwallet/go.sum
index 30a3e2cb6..e25e7b4a1 100644
--- a/systemservices/ethwallet/go.sum
+++ b/systemservices/ethwallet/go.sum
@@ -1,53 +1,59 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78 h1:w+iIsaOQNcT7OZ575w+acHgRric5iCyQh+xv+KJ4HB8=
 github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78/go.mod h1:LmzpDX56iTiv29bbRTIsUNlaFfuhWRQBWjQdVyAevI8=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/Masterminds/goutils v1.1.0/go.mod h1:8cTjp+g8YejhMuvIA5y2vz3BpJxksy863GQaJW2MFNU=
 github.com/Masterminds/semver v1.4.2/go.mod h1:MB6lktGJrhw8PrUyiEoblNEGEQ+RzHPF078ddwwvV3Y=
 github.com/Masterminds/sprig v2.20.0+incompatible/go.mod h1:y6hNFY5UBTIWBxnzTeuNhlNS5hqE0NB0E6fgfo2Br3o=
-github.com/Microsoft/go-winio v0.4.9/go.mod h1:VhR8bwka0BXejwEJY73c50VrPtXAaKcyvVC4A4RozmA=
+github.com/Microsoft/go-winio v0.4.12 h1:xAfWHN1IrQ0NJ9TBC0KBZoqLjzDTr1ML+4MywiUOryc=
 github.com/Microsoft/go-winio v0.4.12/go.mod h1:VhR8bwka0BXejwEJY73c50VrPtXAaKcyvVC4A4RozmA=
-github.com/Netflix/go-expect v0.0.0-20180928190340-9d1f4485533b/go.mod h1:oX5x61PbNXchhh0oikYAH+4Pcfw5LKv21+Jnpr6r6Pc=
+github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5 h1:TngWCqHvy9oXAN6lEVMRuU21PR1EtLVZJmdB18Gu3Rw=
 github.com/Nvveen/Gotty v0.0.0-20120604004816-cd527374f1e5/go.mod h1:lmUJ/7eu/Q8D7ML55dXQrVaamCz2vxCfdQBasLZfHKk=
+github.com/aead/siphash v1.0.1/go.mod h1:Nywa3cDsYNNK3gaciGTWPwHt0wlpNV15vwmswBAUSII=
 github.com/alcortesm/tgz v0.0.0-20161220082320-9c5fe88206d7/go.mod h1:6zEj6s6u/ghQa61ZWa/C2Aw3RkjiTBOix7dkqa1VLIs=
 github.com/allegro/bigcache v1.2.1 h1:hg1sY1raCwic3Vnsvje6TT7/pnZba83LeFck5NrFKSc=
 github.com/allegro/bigcache v1.2.1/go.mod h1:Cb/ax3seSYIx7SuZdm2G2xzfwmv3TPSk2ucNfQESPXM=
 github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239/go.mod h1:2FmKhYUyUczH0OGQWaF5ceTx0UBShxjsH6f8oGKYe2c=
 github.com/aristanetworks/goarista v0.0.0-20190628180533-8e7d5b18fe7a h1:AtHySZzzzJyE9NDlY3MNxkR12HsSxE1QmntYzuc0uEw=
 github.com/aristanetworks/goarista v0.0.0-20190628180533-8e7d5b18fe7a/go.mod h1:D/tb0zPVXnP7fmsLZjtdUhSsumbK/ij54UXjjVgMGxQ=
-github.com/briandowns/spinner v0.0.0-20180822135157-9f016caa1359/go.mod h1:hw/JEQBIE+c/BLI4aKM8UU8v+ZqrD3h7HC27kKt8JQU=
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+github.com/btcsuite/btcd v0.0.0-20190629003639-c26ffa870fd8/go.mod h1:3J08xEfcugPacsc34/LKRU2yO7YmuT8yt28J8k2+rrI=
+github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f/go.mod h1:TdznJufoqS23FtqVCzL0ZqgP5MqXbb4fg/WgDys70nA=
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 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cnf/structhash v0.0.0-20180104161610-62a607eb0224 h1:rnCKRrdSBqc061l0CDuYB+7X3w6w8IK/VCSChJXv62g=
 github.com/cnf/structhash v0.0.0-20180104161610-62a607eb0224/go.mod h1:pCxVEbcm3AMg7ejXyorUXi6HQCzOIBf7zEDVPtw0/U4=
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 github.com/containerd/continuity v0.0.0-20190426062206-aaeac12a7ffc h1:TP+534wVlf61smEIq1nwLLAjQVEK2EADoW3CX9AuT+8=
 github.com/containerd/continuity v0.0.0-20190426062206-aaeac12a7ffc/go.mod h1:GL3xCUCBDV3CZiTSEKksMWbLE66hEyuu9qyDOOqM47Y=
 github.com/cskr/pubsub v1.0.2 h1:vlOzMhl6PFn60gRlTQQsIfVwaPB/B/8MziK8FhEPt/0=
 github.com/cskr/pubsub v1.0.2/go.mod h1:/8MzYXk/NJAz782G8RPkFzXTZVu63VotefPnR9TIRis=
+github.com/davecgh/go-spew v0.0.0-20171005155431-ecdeabc65495/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
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 github.com/ethereum/go-ethereum v1.8.27 h1:d+gkiLaBDk5fn3Pe/xNVaMrB/ozI+AUB2IlVBp29IrY=
 github.com/ethereum/go-ethereum v1.8.27/go.mod h1:PwpWDrCLZrV+tfrhqqF6kPknbISMHaJv9Ln3kPCZLwY=
-github.com/fatih/color v0.0.0-20170926111411-5df930a27be2/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI435gkrCt3MPfRiAkVrwSbHsst4LCFVfpJc=
+github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
-github.com/gliderlabs/ssh v0.1.1/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
 github.com/gliderlabs/ssh v0.2.2/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
 github.com/go-bindata/go-bindata v0.0.0-20181025070752-41975c0ccc30/go.mod h1:xK8Dsgwmeed+BBsSy2XTopBn/8uK2HWuGSnA11C3Joo=
 github.com/go-playground/locales v0.12.1 h1:2FITxuFt/xuCNP1Acdhv62OzaCiviiE4kotfhkmOqEc=
@@ -56,64 +62,60 @@ github.com/go-playground/universal-translator v0.16.0 h1:X++omBR/4cE2MNg91AoC3rm
 github.com/go-playground/universal-translator v0.16.0/go.mod h1:1AnU7NaIRDWWzGEKwgtJRd2xk99HeFyHw3yid4rvQIY=
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@@ -123,29 +125,21 @@ github.com/opencontainers/runc v0.1.1 h1:GlxAyO6x8rfZYN9Tt0Kti5a/cP41iuiO2yYT0IJ
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