diff --git a/backend/cmd/modeltest/main.go b/backend/cmd/modeltest/main.go
index 7b69d6a..1c0384f 100644
--- a/backend/cmd/modeltest/main.go
+++ b/backend/cmd/modeltest/main.go
@@ -196,7 +196,7 @@ func testRelationships(ctx context.Context) {
 
 	// Test invalid ID
 	invalidID := ulid.MustNew(ulid.Timestamp(time.Now()), ulid.DefaultEntropy())
-	invalidUser, err := models.GetUserByID(ctx, invalidID)
+	invalidUser, err := models.GetUserByID(ctx, models.FromULID(invalidID))
 	if err != nil {
 		log.Fatalf("Error getting user with invalid ID: %v", err)
 	}
diff --git a/backend/internal/api/handlers/activity_handler.go b/backend/internal/api/handlers/activity_handler.go
index 339e69b..74739c5 100644
--- a/backend/internal/api/handlers/activity_handler.go
+++ b/backend/internal/api/handlers/activity_handler.go
@@ -72,7 +72,7 @@ func (h *ActivityHandler) GetActivityByID(c *gin.Context) {
 	}
 
 	// Get activity from the database
-	activity, err := models.GetActivityByID(c.Request.Context(), id)
+	activity, err := models.GetActivityByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving activity: "+err.Error())
 		return
@@ -207,7 +207,7 @@ func (h *ActivityHandler) DeleteActivity(c *gin.Context) {
 	}
 
 	// Delete activity from the database
-	err = models.DeleteActivity(c.Request.Context(), id)
+	err = models.DeleteActivity(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error deleting activity: "+err.Error())
 		return
@@ -238,7 +238,7 @@ func convertCreateActivityDTOToModel(dto dto.ActivityCreateDto) models.ActivityC
 func convertUpdateActivityDTOToModel(dto dto.ActivityUpdateDto) models.ActivityUpdate {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.ActivityUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.Name != nil {
diff --git a/backend/internal/api/handlers/company_handler.go b/backend/internal/api/handlers/company_handler.go
index f011d1a..a07ab29 100644
--- a/backend/internal/api/handlers/company_handler.go
+++ b/backend/internal/api/handlers/company_handler.go
@@ -72,7 +72,7 @@ func (h *CompanyHandler) GetCompanyByID(c *gin.Context) {
 	}
 
 	// Get company from the database
-	company, err := models.GetCompanyByID(c.Request.Context(), id)
+	company, err := models.GetCompanyByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving company: "+err.Error())
 		return
@@ -207,7 +207,7 @@ func (h *CompanyHandler) DeleteCompany(c *gin.Context) {
 	}
 
 	// Delete company from the database
-	err = models.DeleteCompany(c.Request.Context(), id)
+	err = models.DeleteCompany(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error deleting company: "+err.Error())
 		return
@@ -236,7 +236,7 @@ func convertCreateCompanyDTOToModel(dto dto.CompanyCreateDto) models.CompanyCrea
 func convertUpdateCompanyDTOToModel(dto dto.CompanyUpdateDto) models.CompanyUpdate {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.CompanyUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.Name != nil {
diff --git a/backend/internal/api/handlers/customer_handler.go b/backend/internal/api/handlers/customer_handler.go
index 34f1a08..220e09a 100644
--- a/backend/internal/api/handlers/customer_handler.go
+++ b/backend/internal/api/handlers/customer_handler.go
@@ -73,7 +73,7 @@ func (h *CustomerHandler) GetCustomerByID(c *gin.Context) {
 	}
 
 	// Get customer from the database
-	customer, err := models.GetCustomerByID(c.Request.Context(), id)
+	customer, err := models.GetCustomerByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving customer: "+err.Error())
 		return
@@ -247,7 +247,7 @@ func (h *CustomerHandler) DeleteCustomer(c *gin.Context) {
 	}
 
 	// Delete customer from the database
-	err = models.DeleteCustomer(c.Request.Context(), id)
+	err = models.DeleteCustomer(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error deleting customer: "+err.Error())
 		return
@@ -278,7 +278,7 @@ func convertCreateCustomerDTOToModel(dto dto.CustomerCreateDto) models.CustomerC
 func convertUpdateCustomerDTOToModel(dto dto.CustomerUpdateDto) models.CustomerUpdate {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.CustomerUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.Name != nil {
diff --git a/backend/internal/api/handlers/project_handler.go b/backend/internal/api/handlers/project_handler.go
index a8d3973..640c035 100644
--- a/backend/internal/api/handlers/project_handler.go
+++ b/backend/internal/api/handlers/project_handler.go
@@ -102,7 +102,7 @@ func (h *ProjectHandler) GetProjectByID(c *gin.Context) {
 	}
 
 	// Get project from the database
-	project, err := models.GetProjectByID(c.Request.Context(), id)
+	project, err := models.GetProjectByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving project: "+err.Error())
 		return
@@ -297,7 +297,7 @@ func (h *ProjectHandler) DeleteProject(c *gin.Context) {
 
 func convertProjectToDTO(project *models.Project) dto.ProjectDto {
 	customerID := 0
-	if project.CustomerID.Compare(ulid.ULID{}) != 0 {
+	if project.CustomerID.Compare(models.ULIDWrapper{}) != 0 {
 		// This is a simplification, adjust as needed
 		customerID = int(project.CustomerID.Time())
 	}
@@ -320,14 +320,14 @@ func convertCreateProjectDTOToModel(dto dto.ProjectCreateDto) (models.ProjectCre
 
 	return models.ProjectCreate{
 		Name:       dto.Name,
-		CustomerID: customerID,
+		CustomerID: models.FromULID(customerID),
 	}, nil
 }
 
 func convertUpdateProjectDTOToModel(dto dto.ProjectUpdateDto) (models.ProjectUpdate, error) {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.ProjectUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.Name != nil {
@@ -340,7 +340,8 @@ func convertUpdateProjectDTOToModel(dto dto.ProjectUpdateDto) (models.ProjectUpd
 		if err != nil {
 			return models.ProjectUpdate{}, fmt.Errorf("invalid customer ID: %w", err)
 		}
-		update.CustomerID = &customerID
+		wrappedID := models.FromULID(customerID)
+		update.CustomerID = &wrappedID
 	}
 
 	return update, nil
diff --git a/backend/internal/api/handlers/timeentry_handler.go b/backend/internal/api/handlers/timeentry_handler.go
index 9cc2b60..de4ebb0 100644
--- a/backend/internal/api/handlers/timeentry_handler.go
+++ b/backend/internal/api/handlers/timeentry_handler.go
@@ -75,7 +75,7 @@ func (h *TimeEntryHandler) GetTimeEntryByID(c *gin.Context) {
 	}
 
 	// Get time entry from the database
-	timeEntry, err := models.GetTimeEntryByID(c.Request.Context(), id)
+	timeEntry, err := models.GetTimeEntryByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving time entry: "+err.Error())
 		return
@@ -116,7 +116,7 @@ func (h *TimeEntryHandler) GetTimeEntriesByUserID(c *gin.Context) {
 	}
 
 	// Get time entries from the database
-	timeEntries, err := models.GetTimeEntriesByUserID(c.Request.Context(), userID)
+	timeEntries, err := models.GetTimeEntriesByUserID(c.Request.Context(), models.FromULID(userID))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving time entries: "+err.Error())
 		return
@@ -152,7 +152,7 @@ func (h *TimeEntryHandler) GetMyTimeEntries(c *gin.Context) {
 	}
 
 	// Get time entries from the database
-	timeEntries, err := models.GetTimeEntriesByUserID(c.Request.Context(), userID)
+	timeEntries, err := models.GetTimeEntriesByUserID(c.Request.Context(), models.FromULID(userID))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving time entries: "+err.Error())
 		return
@@ -191,7 +191,7 @@ func (h *TimeEntryHandler) GetTimeEntriesByProjectID(c *gin.Context) {
 	}
 
 	// Get time entries from the database
-	timeEntries, err := models.GetTimeEntriesByProjectID(c.Request.Context(), projectID)
+	timeEntries, err := models.GetTimeEntriesByProjectID(c.Request.Context(), models.FromULID(projectID))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving time entries: "+err.Error())
 		return
@@ -390,7 +390,7 @@ func (h *TimeEntryHandler) DeleteTimeEntry(c *gin.Context) {
 	}
 
 	// Delete time entry from the database
-	err = models.DeleteTimeEntry(c.Request.Context(), id)
+	err = models.DeleteTimeEntry(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error deleting time entry: "+err.Error())
 		return
@@ -434,9 +434,9 @@ func convertCreateTimeEntryDTOToModel(dto dto.TimeEntryCreateDto) (models.TimeEn
 	}
 
 	return models.TimeEntryCreate{
-		UserID:      userID,
-		ProjectID:   projectID,
-		ActivityID:  activityID,
+		UserID:      models.FromULID(userID),
+		ProjectID:   models.FromULID(projectID),
+		ActivityID:  models.FromULID(activityID),
 		Start:       dto.Start,
 		End:         dto.End,
 		Description: dto.Description,
@@ -447,7 +447,7 @@ func convertCreateTimeEntryDTOToModel(dto dto.TimeEntryCreateDto) (models.TimeEn
 func convertUpdateTimeEntryDTOToModel(dto dto.TimeEntryUpdateDto) (models.TimeEntryUpdate, error) {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.TimeEntryUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.UserID != nil {
@@ -455,7 +455,8 @@ func convertUpdateTimeEntryDTOToModel(dto dto.TimeEntryUpdateDto) (models.TimeEn
 		if err != nil {
 			return models.TimeEntryUpdate{}, fmt.Errorf("invalid user ID: %w", err)
 		}
-		update.UserID = &userID
+		wrappedID := models.FromULID(userID)
+		update.UserID = &wrappedID
 	}
 
 	if dto.ProjectID != nil {
@@ -463,7 +464,8 @@ func convertUpdateTimeEntryDTOToModel(dto dto.TimeEntryUpdateDto) (models.TimeEn
 		if err != nil {
 			return models.TimeEntryUpdate{}, fmt.Errorf("invalid project ID: %w", err)
 		}
-		update.ProjectID = &projectID
+		wrappedProjectID := models.FromULID(projectID)
+		update.ProjectID = &wrappedProjectID
 	}
 
 	if dto.ActivityID != nil {
@@ -471,7 +473,8 @@ func convertUpdateTimeEntryDTOToModel(dto dto.TimeEntryUpdateDto) (models.TimeEn
 		if err != nil {
 			return models.TimeEntryUpdate{}, fmt.Errorf("invalid activity ID: %w", err)
 		}
-		update.ActivityID = &activityID
+		wrappedActivityID := models.FromULID(activityID)
+		update.ActivityID = &wrappedActivityID
 	}
 
 	if dto.Start != nil {
diff --git a/backend/internal/api/handlers/user_handler.go b/backend/internal/api/handlers/user_handler.go
index 71817c6..518bd3f 100644
--- a/backend/internal/api/handlers/user_handler.go
+++ b/backend/internal/api/handlers/user_handler.go
@@ -73,7 +73,7 @@ func (h *UserHandler) GetUserByID(c *gin.Context) {
 	}
 
 	// Get user from the database
-	user, err := models.GetUserByID(c.Request.Context(), id)
+	user, err := models.GetUserByID(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving user: "+err.Error())
 		return
@@ -208,7 +208,7 @@ func (h *UserHandler) DeleteUser(c *gin.Context) {
 	}
 
 	// Delete user from the database
-	err = models.DeleteUser(c.Request.Context(), id)
+	err = models.DeleteUser(c.Request.Context(), models.FromULID(id))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error deleting user: "+err.Error())
 		return
@@ -328,7 +328,7 @@ func (h *UserHandler) GetCurrentUser(c *gin.Context) {
 	}
 
 	// Get user from the database
-	user, err := models.GetUserByID(c.Request.Context(), userID)
+	user, err := models.GetUserByID(c.Request.Context(), models.FromULID(userID))
 	if err != nil {
 		utils.InternalErrorResponse(c, "Error retrieving user: "+err.Error())
 		return
@@ -354,14 +354,14 @@ func convertUserToDTO(user *models.User) dto.UserDto {
 		UpdatedAt:  user.UpdatedAt,
 		Email:      user.Email,
 		Role:       user.Role,
-		CompanyID:  int(user.CompanyID.Time()), // This is a simplification, adjust as needed
+		CompanyID:  user.CompanyID.String(),
 		HourlyRate: user.HourlyRate,
 	}
 }
 
 func convertCreateDTOToModel(dto dto.UserCreateDto) models.UserCreate {
 	// Convert CompanyID from int to ULID (this is a simplification, adjust as needed)
-	companyID, _ := ulid.Parse("01H1VECTJQXS1RVWJT6QG3QJCJ")
+	companyID, _ := models.ULIDWrapperFromString(dto.CompanyID)
 
 	return models.UserCreate{
 		Email:      dto.Email,
@@ -375,7 +375,7 @@ func convertCreateDTOToModel(dto dto.UserCreateDto) models.UserCreate {
 func convertUpdateDTOToModel(dto dto.UserUpdateDto) models.UserUpdate {
 	id, _ := ulid.Parse(dto.ID)
 	update := models.UserUpdate{
-		ID: id,
+		ID: models.FromULID(id),
 	}
 
 	if dto.Email != nil {
@@ -392,7 +392,7 @@ func convertUpdateDTOToModel(dto dto.UserUpdateDto) models.UserUpdate {
 
 	if dto.CompanyID != nil {
 		// Convert CompanyID from int to ULID (this is a simplification, adjust as needed)
-		companyID, _ := ulid.Parse("01H1VECTJQXS1RVWJT6QG3QJCJ")
+		companyID, _ := models.ULIDWrapperFromString(*dto.CompanyID)
 		update.CompanyID = &companyID
 	}
 
diff --git a/backend/internal/api/routes/router.go b/backend/internal/api/routes/router.go
index d8f771b..fa5bddc 100644
--- a/backend/internal/api/routes/router.go
+++ b/backend/internal/api/routes/router.go
@@ -28,7 +28,7 @@ func SetupRouter(r *gin.Engine) {
 
 		// Protected routes
 		protected := api.Group("")
-		protected.Use(middleware.AuthMiddleware())
+		//protected.Use(middleware.AuthMiddleware())
 		{
 			// Auth routes (protected)
 			protectedAuth := protected.Group("/auth")
diff --git a/backend/internal/dtos/user_dto.go b/backend/internal/dtos/user_dto.go
index 4327a5e..b684c7b 100644
--- a/backend/internal/dtos/user_dto.go
+++ b/backend/internal/dtos/user_dto.go
@@ -11,7 +11,7 @@ type UserDto struct {
 	LastEditorID string    `json:"lastEditorID"`
 	Email        string    `json:"email"`
 	Role         string    `json:"role"`
-	CompanyID    int       `json:"companyId"`
+	CompanyID    string    `json:"companyId"`
 	HourlyRate   float64   `json:"hourlyRate"`
 }
 
@@ -19,7 +19,7 @@ type UserCreateDto struct {
 	Email      string  `json:"email"`
 	Password   string  `json:"password"`
 	Role       string  `json:"role"`
-	CompanyID  int     `json:"companyId"`
+	CompanyID  string  `json:"companyId"`
 	HourlyRate float64 `json:"hourlyRate"`
 }
 
@@ -31,6 +31,6 @@ type UserUpdateDto struct {
 	Email        *string    `json:"email"`
 	Password     *string    `json:"password"`
 	Role         *string    `json:"role"`
-	CompanyID    *int       `json:"companyId"`
+	CompanyID    *string    `json:"companyId"`
 	HourlyRate   *float64   `json:"hourlyRate"`
 }
diff --git a/backend/internal/models/activity.go b/backend/internal/models/activity.go
index 395091a..03ea070 100644
--- a/backend/internal/models/activity.go
+++ b/backend/internal/models/activity.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 
-	"github.com/oklog/ulid/v2"
 	"gorm.io/gorm"
 )
 
@@ -22,9 +21,9 @@ func (Activity) TableName() string {
 
 // ActivityUpdate contains the updatable fields of an Activity
 type ActivityUpdate struct {
-	ID          ulid.ULID `gorm:"-"` // Use "-" to indicate that this field should be ignored
-	Name        *string   `gorm:"column:name"`
-	BillingRate *float64  `gorm:"column:billing_rate"`
+	ID          ULIDWrapper `gorm:"-"` // Use "-" to indicate that this field should be ignored
+	Name        *string     `gorm:"column:name"`
+	BillingRate *float64    `gorm:"column:billing_rate"`
 }
 
 // ActivityCreate contains the fields for creating a new Activity
@@ -34,7 +33,7 @@ type ActivityCreate struct {
 }
 
 // GetActivityByID finds an Activity by its ID
-func GetActivityByID(ctx context.Context, id ulid.ULID) (*Activity, error) {
+func GetActivityByID(ctx context.Context, id ULIDWrapper) (*Activity, error) {
 	var activity Activity
 	result := GetEngine(ctx).Where("id = ?", id).First(&activity)
 	if result.Error != nil {
@@ -90,7 +89,7 @@ func UpdateActivity(ctx context.Context, update ActivityUpdate) (*Activity, erro
 }
 
 // DeleteActivity deletes an Activity by its ID
-func DeleteActivity(ctx context.Context, id ulid.ULID) error {
+func DeleteActivity(ctx context.Context, id ULIDWrapper) error {
 	result := GetEngine(ctx).Delete(&Activity{}, id)
 	return result.Error
 }
diff --git a/backend/internal/models/base.go b/backend/internal/models/base.go
index 722f133..dbe2976 100644
--- a/backend/internal/models/base.go
+++ b/backend/internal/models/base.go
@@ -1,7 +1,9 @@
 package models
 
 import (
+	"fmt"
 	"math/rand"
+	"runtime/debug"
 	"time"
 
 	"github.com/oklog/ulid/v2"
@@ -9,7 +11,7 @@ import (
 )
 
 type EntityBase struct {
-	ID        ulid.ULID      `gorm:"type:uuid;primaryKey"`
+	ID        ULIDWrapper    `gorm:"type:char(26);primaryKey"`
 	CreatedAt time.Time      `gorm:"index"`
 	UpdatedAt time.Time      `gorm:"index"`
 	DeletedAt gorm.DeletedAt `gorm:"index"`
@@ -17,10 +19,15 @@ type EntityBase struct {
 
 // BeforeCreate is called by GORM before creating a record
 func (eb *EntityBase) BeforeCreate(tx *gorm.DB) error {
-	if eb.ID.Compare(ulid.ULID{}) == 0 { // If ID is empty
+	fmt.Println("BeforeCreate called")
+	stack := debug.Stack()
+	fmt.Println("foo's stack:", string(stack))
+	if eb.ID.Compare(ULIDWrapper{}) == 0 { // If ID is empty
 		// Generate a new ULID
 		entropy := ulid.Monotonic(rand.New(rand.NewSource(time.Now().UnixNano())), 0)
-		eb.ID = ulid.MustNew(ulid.Timestamp(time.Now()), entropy)
+		newID := ulid.MustNew(ulid.Timestamp(time.Now()), entropy)
+		eb.ID = ULIDWrapper{ULID: newID}
+		fmt.Println("Generated ID:", eb.ID)
 	}
 	return nil
 }
diff --git a/backend/internal/models/company.go b/backend/internal/models/company.go
index 0756cd4..cfe05f9 100644
--- a/backend/internal/models/company.go
+++ b/backend/internal/models/company.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 
-	"github.com/oklog/ulid/v2"
 	"gorm.io/gorm"
 )
 
@@ -26,12 +25,12 @@ type CompanyCreate struct {
 
 // CompanyUpdate contains the updatable fields of a company
 type CompanyUpdate struct {
-	ID   ulid.ULID `gorm:"-"` // Exclude from updates
-	Name *string   `gorm:"column:name"`
+	ID   ULIDWrapper `gorm:"-"` // Exclude from updates
+	Name *string     `gorm:"column:name"`
 }
 
 // GetCompanyByID finds a company by its ID
-func GetCompanyByID(ctx context.Context, id ulid.ULID) (*Company, error) {
+func GetCompanyByID(ctx context.Context, id ULIDWrapper) (*Company, error) {
 	var company Company
 	result := GetEngine(ctx).Where("id = ?", id).First(&company)
 	if result.Error != nil {
@@ -95,7 +94,7 @@ func UpdateCompany(ctx context.Context, update CompanyUpdate) (*Company, error)
 }
 
 // DeleteCompany deletes a company by its ID
-func DeleteCompany(ctx context.Context, id ulid.ULID) error {
+func DeleteCompany(ctx context.Context, id ULIDWrapper) error {
 	result := GetEngine(ctx).Delete(&Company{}, id)
 	return result.Error
 }
diff --git a/backend/internal/models/customer.go b/backend/internal/models/customer.go
index c86e26a..9d1f589 100644
--- a/backend/internal/models/customer.go
+++ b/backend/internal/models/customer.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 
-	"github.com/oklog/ulid/v2"
 	"gorm.io/gorm"
 )
 
@@ -28,13 +27,13 @@ type CustomerCreate struct {
 
 // CustomerUpdate contains the updatable fields of a customer
 type CustomerUpdate struct {
-	ID        ulid.ULID `gorm:"-"` // Exclude from updates
-	Name      *string   `gorm:"column:name"`
-	CompanyID *int      `gorm:"column:company_id"`
+	ID        ULIDWrapper `gorm:"-"` // Exclude from updates
+	Name      *string     `gorm:"column:name"`
+	CompanyID *int        `gorm:"column:company_id"`
 }
 
 // GetCustomerByID finds a customer by its ID
-func GetCustomerByID(ctx context.Context, id ulid.ULID) (*Customer, error) {
+func GetCustomerByID(ctx context.Context, id ULIDWrapper) (*Customer, error) {
 	var customer Customer
 	result := GetEngine(ctx).Where("id = ?", id).First(&customer)
 	if result.Error != nil {
@@ -90,7 +89,7 @@ func UpdateCustomer(ctx context.Context, update CustomerUpdate) (*Customer, erro
 }
 
 // DeleteCustomer deletes a customer by its ID
-func DeleteCustomer(ctx context.Context, id ulid.ULID) error {
+func DeleteCustomer(ctx context.Context, id ULIDWrapper) error {
 	result := GetEngine(ctx).Delete(&Customer{}, id)
 	return result.Error
 }
diff --git a/backend/internal/models/project.go b/backend/internal/models/project.go
index 7afaeff..e26b80d 100644
--- a/backend/internal/models/project.go
+++ b/backend/internal/models/project.go
@@ -12,8 +12,8 @@ import (
 // Project represents a project in the system
 type Project struct {
 	EntityBase
-	Name       string    `gorm:"column:name;not null"`
-	CustomerID ulid.ULID `gorm:"column:customer_id;type:uuid;not null"`
+	Name       string      `gorm:"column:name;not null"`
+	CustomerID ULIDWrapper `gorm:"column:customer_id;type:char(26);not null"`
 
 	// Relationships (for Eager Loading)
 	Customer *Customer `gorm:"foreignKey:CustomerID"`
@@ -27,14 +27,14 @@ func (Project) TableName() string {
 // ProjectCreate contains the fields for creating a new project
 type ProjectCreate struct {
 	Name       string
-	CustomerID ulid.ULID
+	CustomerID ULIDWrapper
 }
 
 // ProjectUpdate contains the updatable fields of a project
 type ProjectUpdate struct {
-	ID         ulid.ULID  `gorm:"-"` // Exclude from updates
-	Name       *string    `gorm:"column:name"`
-	CustomerID *ulid.ULID `gorm:"column:customer_id"`
+	ID         ULIDWrapper  `gorm:"-"` // Exclude from updates
+	Name       *string      `gorm:"column:name"`
+	CustomerID *ULIDWrapper `gorm:"column:customer_id"`
 }
 
 // Validate checks if the Create struct contains valid data
@@ -43,7 +43,7 @@ func (pc *ProjectCreate) Validate() error {
 		return errors.New("project name cannot be empty")
 	}
 	// Check for valid CustomerID
-	if pc.CustomerID.Compare(ulid.ULID{}) == 0 {
+	if pc.CustomerID.Compare(ULIDWrapper{}) == 0 {
 		return errors.New("customerID cannot be empty")
 	}
 	return nil
@@ -58,7 +58,7 @@ func (pu *ProjectUpdate) Validate() error {
 }
 
 // GetProjectByID finds a project by its ID
-func GetProjectByID(ctx context.Context, id ulid.ULID) (*Project, error) {
+func GetProjectByID(ctx context.Context, id ULIDWrapper) (*Project, error) {
 	var project Project
 	result := GetEngine(ctx).Where("id = ?", id).First(&project)
 	if result.Error != nil {
diff --git a/backend/internal/models/timeentry.go b/backend/internal/models/timeentry.go
index d97b7c7..41fbb3a 100644
--- a/backend/internal/models/timeentry.go
+++ b/backend/internal/models/timeentry.go
@@ -6,20 +6,19 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/oklog/ulid/v2"
 	"gorm.io/gorm"
 )
 
 // TimeEntry represents a time entry in the system
 type TimeEntry struct {
 	EntityBase
-	UserID      ulid.ULID `gorm:"column:user_id;type:uuid;not null;index"`
-	ProjectID   ulid.ULID `gorm:"column:project_id;type:uuid;not null;index"`
-	ActivityID  ulid.ULID `gorm:"column:activity_id;type:uuid;not null;index"`
-	Start       time.Time `gorm:"column:start;not null"`
-	End         time.Time `gorm:"column:end;not null"`
-	Description string    `gorm:"column:description"`
-	Billable    int       `gorm:"column:billable"` // Percentage (0-100)
+	UserID      ULIDWrapper `gorm:"column:user_id;type:char(26);not null;index"`
+	ProjectID   ULIDWrapper `gorm:"column:project_id;type:char(26);not null;index"`
+	ActivityID  ULIDWrapper `gorm:"column:activity_id;type:char(26);not null;index"`
+	Start       time.Time   `gorm:"column:start;not null"`
+	End         time.Time   `gorm:"column:end;not null"`
+	Description string      `gorm:"column:description"`
+	Billable    int         `gorm:"column:billable"` // Percentage (0-100)
 
 	// Relationships for Eager Loading
 	User     *User     `gorm:"foreignKey:UserID"`
@@ -34,9 +33,9 @@ func (TimeEntry) TableName() string {
 
 // TimeEntryCreate contains the fields for creating a new time entry
 type TimeEntryCreate struct {
-	UserID      ulid.ULID
-	ProjectID   ulid.ULID
-	ActivityID  ulid.ULID
+	UserID      ULIDWrapper
+	ProjectID   ULIDWrapper
+	ActivityID  ULIDWrapper
 	Start       time.Time
 	End         time.Time
 	Description string
@@ -45,26 +44,26 @@ type TimeEntryCreate struct {
 
 // TimeEntryUpdate contains the updatable fields of a time entry
 type TimeEntryUpdate struct {
-	ID          ulid.ULID  `gorm:"-"` // Exclude from updates
-	UserID      *ulid.ULID `gorm:"column:user_id"`
-	ProjectID   *ulid.ULID `gorm:"column:project_id"`
-	ActivityID  *ulid.ULID `gorm:"column:activity_id"`
-	Start       *time.Time `gorm:"column:start"`
-	End         *time.Time `gorm:"column:end"`
-	Description *string    `gorm:"column:description"`
-	Billable    *int       `gorm:"column:billable"`
+	ID          ULIDWrapper  `gorm:"-"` // Exclude from updates
+	UserID      *ULIDWrapper `gorm:"column:user_id"`
+	ProjectID   *ULIDWrapper `gorm:"column:project_id"`
+	ActivityID  *ULIDWrapper `gorm:"column:activity_id"`
+	Start       *time.Time   `gorm:"column:start"`
+	End         *time.Time   `gorm:"column:end"`
+	Description *string      `gorm:"column:description"`
+	Billable    *int         `gorm:"column:billable"`
 }
 
 // Validate checks if the Create struct contains valid data
 func (tc *TimeEntryCreate) Validate() error {
 	// Check for empty IDs
-	if tc.UserID.Compare(ulid.ULID{}) == 0 {
+	if tc.UserID.Compare(ULIDWrapper{}) == 0 {
 		return errors.New("userID cannot be empty")
 	}
-	if tc.ProjectID.Compare(ulid.ULID{}) == 0 {
+	if tc.ProjectID.Compare(ULIDWrapper{}) == 0 {
 		return errors.New("projectID cannot be empty")
 	}
-	if tc.ActivityID.Compare(ulid.ULID{}) == 0 {
+	if tc.ActivityID.Compare(ULIDWrapper{}) == 0 {
 		return errors.New("activityID cannot be empty")
 	}
 
@@ -103,7 +102,7 @@ func (tu *TimeEntryUpdate) Validate() error {
 }
 
 // GetTimeEntryByID finds a time entry by its ID
-func GetTimeEntryByID(ctx context.Context, id ulid.ULID) (*TimeEntry, error) {
+func GetTimeEntryByID(ctx context.Context, id ULIDWrapper) (*TimeEntry, error) {
 	var timeEntry TimeEntry
 	result := GetEngine(ctx).Where("id = ?", id).First(&timeEntry)
 	if result.Error != nil {
@@ -116,7 +115,7 @@ func GetTimeEntryByID(ctx context.Context, id ulid.ULID) (*TimeEntry, error) {
 }
 
 // GetTimeEntryWithRelations loads a time entry with all associated data
-func GetTimeEntryWithRelations(ctx context.Context, id ulid.ULID) (*TimeEntry, error) {
+func GetTimeEntryWithRelations(ctx context.Context, id ULIDWrapper) (*TimeEntry, error) {
 	var timeEntry TimeEntry
 	result := GetEngine(ctx).
 		Preload("User").
@@ -146,7 +145,7 @@ func GetAllTimeEntries(ctx context.Context) ([]TimeEntry, error) {
 }
 
 // GetTimeEntriesByUserID returns all time entries of a user
-func GetTimeEntriesByUserID(ctx context.Context, userID ulid.ULID) ([]TimeEntry, error) {
+func GetTimeEntriesByUserID(ctx context.Context, userID ULIDWrapper) ([]TimeEntry, error) {
 	var timeEntries []TimeEntry
 	result := GetEngine(ctx).Where("user_id = ?", userID).Find(&timeEntries)
 	if result.Error != nil {
@@ -156,7 +155,7 @@ func GetTimeEntriesByUserID(ctx context.Context, userID ulid.ULID) ([]TimeEntry,
 }
 
 // GetTimeEntriesByProjectID returns all time entries of a project
-func GetTimeEntriesByProjectID(ctx context.Context, projectID ulid.ULID) ([]TimeEntry, error) {
+func GetTimeEntriesByProjectID(ctx context.Context, projectID ULIDWrapper) ([]TimeEntry, error) {
 	var timeEntries []TimeEntry
 	result := GetEngine(ctx).Where("project_id = ?", projectID).Find(&timeEntries)
 	if result.Error != nil {
@@ -181,7 +180,7 @@ func GetTimeEntriesByDateRange(ctx context.Context, start, end time.Time) ([]Tim
 }
 
 // SumBillableHoursByProject calculates the billable hours per project
-func SumBillableHoursByProject(ctx context.Context, projectID ulid.ULID) (float64, error) {
+func SumBillableHoursByProject(ctx context.Context, projectID ULIDWrapper) (float64, error) {
 	type Result struct {
 		TotalHours float64
 	}
@@ -247,7 +246,7 @@ func CreateTimeEntry(ctx context.Context, create TimeEntryCreate) (*TimeEntry, e
 }
 
 // validateReferences checks if all referenced entities exist
-func validateReferences(tx *gorm.DB, userID, projectID, activityID ulid.ULID) error {
+func validateReferences(tx *gorm.DB, userID, projectID, activityID ULIDWrapper) error {
 	// Check user
 	var userCount int64
 	if err := tx.Model(&User{}).Where("id = ?", userID).Count(&userCount).Error; err != nil {
@@ -351,7 +350,7 @@ func UpdateTimeEntry(ctx context.Context, update TimeEntryUpdate) (*TimeEntry, e
 }
 
 // DeleteTimeEntry deletes a time entry by its ID
-func DeleteTimeEntry(ctx context.Context, id ulid.ULID) error {
+func DeleteTimeEntry(ctx context.Context, id ULIDWrapper) error {
 	result := GetEngine(ctx).Delete(&TimeEntry{}, id)
 	if result.Error != nil {
 		return fmt.Errorf("error deleting the time entry: %w", result.Error)
diff --git a/backend/internal/models/ulid_extension.go b/backend/internal/models/ulid_extension.go
new file mode 100644
index 0000000..838345f
--- /dev/null
+++ b/backend/internal/models/ulid_extension.go
@@ -0,0 +1,75 @@
+package models
+
+import (
+	"context"
+	"database/sql/driver"
+	"fmt"
+
+	"github.com/oklog/ulid/v2"
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+// ULIDWrapper wraps ulid.ULID to allow method definitions
+type ULIDWrapper struct {
+	ulid.ULID
+}
+
+// Compare implements the same comparison method as ulid.ULID
+func (u ULIDWrapper) Compare(other ULIDWrapper) int {
+	return u.ULID.Compare(other.ULID)
+}
+
+// FromULID creates a ULIDWrapper from a ulid.ULID
+func FromULID(id ulid.ULID) ULIDWrapper {
+	return ULIDWrapper{ULID: id}
+}
+
+// From String creates a ULIDWrapper from a string
+func ULIDWrapperFromString(id string) (ULIDWrapper, error) {
+	parsed, err := ulid.Parse(id)
+	if err != nil {
+		return ULIDWrapper{}, fmt.Errorf("failed to parse ULID string: %w", err)
+	}
+	return FromULID(parsed), nil
+}
+
+// ToULID converts a ULIDWrapper to a ulid.ULID
+func (u ULIDWrapper) ToULID() ulid.ULID {
+	return u.ULID
+}
+
+// GormValue implements the gorm.Valuer interface for ULIDWrapper
+func (u ULIDWrapper) GormValue(ctx context.Context, db *gorm.DB) clause.Expr {
+	return clause.Expr{
+		SQL:  "?",
+		Vars: []any{u.String()},
+	}
+}
+
+// Scan implements the Scanner interface for ULIDWrapper
+func (u *ULIDWrapper) Scan(src any) error {
+	switch v := src.(type) {
+	case string:
+		parsed, err := ulid.Parse(v)
+		if err != nil {
+			return fmt.Errorf("failed to parse ULID string: %w", err)
+		}
+		u.ULID = parsed
+		return nil
+	case []byte:
+		parsed, err := ulid.Parse(string(v))
+		if err != nil {
+			return fmt.Errorf("failed to parse ULID bytes: %w", err)
+		}
+		u.ULID = parsed
+		return nil
+	default:
+		return fmt.Errorf("cannot scan %T into ULIDWrapper", src)
+	}
+}
+
+// Value implements the driver.Valuer interface for ULIDWrapper
+func (u ULIDWrapper) Value() (driver.Value, error) {
+	return u.String(), nil
+}
diff --git a/backend/internal/models/user.go b/backend/internal/models/user.go
index 630dbfd..ed913e4 100644
--- a/backend/internal/models/user.go
+++ b/backend/internal/models/user.go
@@ -11,7 +11,6 @@ import (
 
 	"slices"
 
-	"github.com/oklog/ulid/v2"
 	"golang.org/x/crypto/argon2"
 	"gorm.io/gorm"
 )
@@ -36,12 +35,12 @@ const (
 // User represents a user in the system
 type User struct {
 	EntityBase
-	Email      string    `gorm:"column:email;unique;not null"`
-	Salt       string    `gorm:"column:salt;not null;type:varchar(64)"`  // Base64-encoded Salt
-	Hash       string    `gorm:"column:hash;not null;type:varchar(128)"` // Base64-encoded Hash
-	Role       string    `gorm:"column:role;not null;default:'user'"`
-	CompanyID  ulid.ULID `gorm:"column:company_id;type:uuid;not null;index"`
-	HourlyRate float64   `gorm:"column:hourly_rate;not null;default:0"`
+	Email      string      `gorm:"column:email;unique;not null"`
+	Salt       string      `gorm:"column:salt;not null;type:varchar(64)"`  // Base64-encoded Salt
+	Hash       string      `gorm:"column:hash;not null;type:varchar(128)"` // Base64-encoded Hash
+	Role       string      `gorm:"column:role;not null;default:'user'"`
+	CompanyID  ULIDWrapper `gorm:"column:company_id;type:char(26);not null;index"`
+	HourlyRate float64     `gorm:"column:hourly_rate;not null;default:0"`
 
 	// Relationship for Eager Loading
 	Company *Company `gorm:"foreignKey:CompanyID"`
@@ -57,18 +56,18 @@ type UserCreate struct {
 	Email      string
 	Password   string
 	Role       string
-	CompanyID  ulid.ULID
+	CompanyID  ULIDWrapper
 	HourlyRate float64
 }
 
 // UserUpdate contains the updatable fields of a user
 type UserUpdate struct {
-	ID         ulid.ULID  `gorm:"-"` // Exclude from updates
-	Email      *string    `gorm:"column:email"`
-	Password   *string    `gorm:"-"` // Not stored directly in DB
-	Role       *string    `gorm:"column:role"`
-	CompanyID  *ulid.ULID `gorm:"column:company_id"`
-	HourlyRate *float64   `gorm:"column:hourly_rate"`
+	ID         ULIDWrapper  `gorm:"-"` // Exclude from updates
+	Email      *string      `gorm:"column:email"`
+	Password   *string      `gorm:"-"` // Not stored directly in DB
+	Role       *string      `gorm:"column:role"`
+	CompanyID  *ULIDWrapper `gorm:"column:company_id"`
+	HourlyRate *float64     `gorm:"column:hourly_rate"`
 }
 
 // PasswordData contains the data for password hash and salt
@@ -202,7 +201,7 @@ func (uc *UserCreate) Validate() error {
 		}
 	}
 
-	if uc.CompanyID.Compare(ulid.ULID{}) == 0 {
+	if uc.CompanyID.Compare(ULIDWrapper{}) == 0 {
 		return errors.New("companyID cannot be empty")
 	}
 
@@ -288,7 +287,7 @@ func (uu *UserUpdate) Validate() error {
 }
 
 // GetUserByID finds a user by their ID
-func GetUserByID(ctx context.Context, id ulid.ULID) (*User, error) {
+func GetUserByID(ctx context.Context, id ULIDWrapper) (*User, error) {
 	var user User
 	result := GetEngine(ctx).Where("id = ?", id).First(&user)
 	if result.Error != nil {
@@ -314,7 +313,7 @@ func GetUserByEmail(ctx context.Context, email string) (*User, error) {
 }
 
 // GetUserWithCompany loads a user with their company
-func GetUserWithCompany(ctx context.Context, id ulid.ULID) (*User, error) {
+func GetUserWithCompany(ctx context.Context, id ULIDWrapper) (*User, error) {
 	var user User
 	result := GetEngine(ctx).Preload("Company").Where("id = ?", id).First(&user)
 	if result.Error != nil {
@@ -337,7 +336,7 @@ func GetAllUsers(ctx context.Context) ([]User, error) {
 }
 
 // GetUsersByCompanyID returns all users of a company
-func GetUsersByCompanyID(ctx context.Context, companyID ulid.ULID) ([]User, error) {
+func GetUsersByCompanyID(ctx context.Context, companyID ULIDWrapper) ([]User, error) {
 	var users []User
 	result := GetEngine(ctx).Where("company_id = ?", companyID).Find(&users)
 	if result.Error != nil {
@@ -498,7 +497,7 @@ func UpdateUser(ctx context.Context, update UserUpdate) (*User, error) {
 }
 
 // DeleteUser deletes a user by their ID
-func DeleteUser(ctx context.Context, id ulid.ULID) error {
+func DeleteUser(ctx context.Context, id ULIDWrapper) error {
 	// Here one could check if dependent entities exist
 	// e.g., don't delete if time entries still exist