diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ff7207..4a48af9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 - Adjusted Mojang usernames filter to be stickier according to their docs
+- `/profile/{username}` endpoint now returns the correct signature for the custom property as well.
 
 ### Changed
 - Bumped Go version to 1.21.
diff --git a/README.md b/README.md
index 8db7f9e..b7b7319 100644
--- a/README.md
+++ b/README.md
@@ -243,11 +243,12 @@ Response example:
     "properties": [
         {
             "name": "textures",
-            "signature": "signature value",
+            "signature": "textures signature value",
             "value": "base64 encoded value"
         },
         {
             "name": "chrly",
+            "signature": "custom property signature value",
             "value": "how do you tame a horse in Minecraft?"
         }
     ]
diff --git a/di/handlers.go b/di/handlers.go
index a0ed9dc..221ea7b 100644
--- a/di/handlers.go
+++ b/di/handlers.go
@@ -106,19 +106,24 @@ func newSkinsystemHandler(
 	capesRepository CapesRepository,
 	mojangTexturesProvider MojangTexturesProvider,
 	texturesSigner TexturesSigner,
-) *mux.Router {
+) (*mux.Router, error) {
 	config.SetDefault("textures.extra_param_name", "chrly")
 	config.SetDefault("textures.extra_param_value", "how do you tame a horse in Minecraft?")
 
-	return (&Skinsystem{
-		Emitter:                 emitter,
-		SkinsRepo:               skinsRepository,
-		CapesRepo:               capesRepository,
-		MojangTexturesProvider:  mojangTexturesProvider,
-		TexturesSigner:          texturesSigner,
-		TexturesExtraParamName:  config.GetString("textures.extra_param_name"),
-		TexturesExtraParamValue: config.GetString("textures.extra_param_value"),
-	}).Handler()
+	app, err := NewSkinsystem(
+		emitter,
+		skinsRepository,
+		capesRepository,
+		mojangTexturesProvider,
+		texturesSigner,
+		config.GetString("textures.extra_param_name"),
+		config.GetString("textures.extra_param_value"),
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return app.Handler(), nil
 }
 
 func newApiHandler(skinsRepository SkinsRepository) *mux.Router {
diff --git a/http/skinsystem.go b/http/skinsystem.go
index f15a7e5..555af34 100644
--- a/http/skinsystem.go
+++ b/http/skinsystem.go
@@ -6,6 +6,7 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"encoding/pem"
+	"fmt"
 	"io"
 	"net/http"
 	"strings"
@@ -43,12 +44,39 @@ type TexturesSigner interface {
 
 type Skinsystem struct {
 	Emitter
-	SkinsRepo               SkinsRepository
-	CapesRepo               CapesRepository
-	MojangTexturesProvider  MojangTexturesProvider
-	TexturesSigner          TexturesSigner
-	TexturesExtraParamName  string
-	TexturesExtraParamValue string
+	SkinsRepo                   SkinsRepository
+	CapesRepo                   CapesRepository
+	MojangTexturesProvider      MojangTexturesProvider
+	TexturesSigner              TexturesSigner
+	TexturesExtraParamName      string
+	TexturesExtraParamValue     string
+	texturesExtraParamSignature string
+}
+
+func NewSkinsystem(
+	emitter Emitter,
+	skinsRepo SkinsRepository,
+	capesRepo CapesRepository,
+	mojangTexturesProvider MojangTexturesProvider,
+	texturesSigner TexturesSigner,
+	texturesExtraParamName string,
+	texturesExtraParamValue string,
+) (*Skinsystem, error) {
+	texturesExtraParamSignature, err := texturesSigner.SignTextures(texturesExtraParamValue)
+	if err != nil {
+		return nil, fmt.Errorf("unable to generate signature for textures extra param: %w", err)
+	}
+
+	return &Skinsystem{
+		Emitter:                     emitter,
+		SkinsRepo:                   skinsRepo,
+		CapesRepo:                   capesRepo,
+		MojangTexturesProvider:      mojangTexturesProvider,
+		TexturesSigner:              texturesSigner,
+		TexturesExtraParamName:      texturesExtraParamName,
+		TexturesExtraParamValue:     texturesExtraParamValue,
+		texturesExtraParamSignature: texturesExtraParamSignature,
+	}, nil
 }
 
 type profile struct {
@@ -215,14 +243,20 @@ func (ctx *Skinsystem) profileHandler(response http.ResponseWriter, request *htt
 		Name:  "textures",
 		Value: texturesPropEncodedValue,
 	}
+	customProp := &mojang.Property{
+		Name:  ctx.TexturesExtraParamName,
+		Value: ctx.TexturesExtraParamValue,
+	}
 
 	if request.URL.Query().Get("unsigned") == "false" {
-		signature, err := ctx.TexturesSigner.SignTextures(texturesProp.Value)
+		customProp.Signature = ctx.texturesExtraParamSignature
+
+		texturesSignature, err := ctx.TexturesSigner.SignTextures(texturesProp.Value)
 		if err != nil {
 			panic(err)
 		}
 
-		texturesProp.Signature = signature
+		texturesProp.Signature = texturesSignature
 	}
 
 	profileResponse := &mojang.SignedTexturesResponse{
@@ -230,10 +264,7 @@ func (ctx *Skinsystem) profileHandler(response http.ResponseWriter, request *htt
 		Name: profile.Username,
 		Props: []*mojang.Property{
 			texturesProp,
-			{
-				Name:  ctx.TexturesExtraParamName,
-				Value: ctx.TexturesExtraParamValue,
-			},
+			customProp,
 		},
 	}
 
diff --git a/http/skinsystem_test.go b/http/skinsystem_test.go
index a3e0de1..9e51f87 100644
--- a/http/skinsystem_test.go
+++ b/http/skinsystem_test.go
@@ -142,15 +142,17 @@ func (suite *skinsystemTestSuite) SetupTest() {
 	suite.TexturesSigner = &texturesSignerMock{}
 	suite.Emitter = &emitterMock{}
 
-	suite.App = &Skinsystem{
-		SkinsRepo:               suite.SkinsRepository,
-		CapesRepo:               suite.CapesRepository,
-		MojangTexturesProvider:  suite.MojangTexturesProvider,
-		TexturesSigner:          suite.TexturesSigner,
-		Emitter:                 suite.Emitter,
-		TexturesExtraParamName:  "texturesParamName",
-		TexturesExtraParamValue: "texturesParamValue",
-	}
+	suite.TexturesSigner.On("SignTextures", "texturesParamValue").Times(1).Return("texturesParamSignature", nil)
+
+	suite.App, _ = NewSkinsystem(
+		suite.Emitter,
+		suite.SkinsRepository,
+		suite.CapesRepository,
+		suite.MojangTexturesProvider,
+		suite.TexturesSigner,
+		"texturesParamName",
+		"texturesParamValue",
+	)
 }
 
 func (suite *skinsystemTestSuite) TearDownTest() {
@@ -801,6 +803,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -830,6 +833,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -859,6 +863,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -892,6 +897,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -925,6 +931,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -954,6 +961,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -983,6 +991,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -1012,6 +1021,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]
@@ -1054,6 +1064,7 @@ var profileTestsCases = []*profileTestCase{
 					},
 					{
 						"name": "texturesParamName",
+						"signature": "texturesParamSignature",
 						"value": "texturesParamValue"
 					}
 				]