diff --git a/examples/shipping/README.md b/examples/shipping/README.md
index cbcc4df..1a9a14e 100644
--- a/examples/shipping/README.md
+++ b/examples/shipping/README.md
@@ -16,7 +16,7 @@
 
 There are also a few pure domain packages that contain some intricate business-logic. They provide domain objects and services that are used by each application service to provide interesting use-cases for the user.
 
-`repository` contains in-memory implementations for the repositories found in the domain packages.
+`inmem` contains in-memory implementations for the repositories found in the domain packages.
 
 The `routing` package provides a _domain service_ that is used to query an external application for possible routes.
 
diff --git a/examples/shipping/booking/endpoint.go b/examples/shipping/booking/endpoint.go
index b9864d2..fe74955 100644
--- a/examples/shipping/booking/endpoint.go
+++ b/examples/shipping/booking/endpoint.go
@@ -6,6 +6,7 @@
 	"golang.org/x/net/context"
 
 	"github.com/go-kit/kit/endpoint"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
 )
diff --git a/examples/shipping/booking/instrumenting.go b/examples/shipping/booking/instrumenting.go
index 8531796..b9b03b9 100644
--- a/examples/shipping/booking/instrumenting.go
+++ b/examples/shipping/booking/instrumenting.go
@@ -16,21 +16,21 @@
 }
 
 // NewInstrumentingService returns an instance of an instrumenting Service.
-func NewInstrumentingService(requestCount metrics.Counter, requestLatency metrics.Histogram, s Service) Service {
+func NewInstrumentingService(counter metrics.Counter, latency metrics.Histogram, s Service) Service {
 	return &instrumentingService{
-		requestCount:   requestCount,
-		requestLatency: requestLatency,
+		requestCount:   counter,
+		requestLatency: latency,
 		Service:        s,
 	}
 }
 
-func (s *instrumentingService) BookNewCargo(origin, destination location.UNLocode, arrivalDeadline time.Time) (cargo.TrackingID, error) {
+func (s *instrumentingService) BookNewCargo(origin, destination location.UNLocode, deadline time.Time) (cargo.TrackingID, error) {
 	defer func(begin time.Time) {
 		s.requestCount.With("method", "book").Add(1)
 		s.requestLatency.With("method", "book").Observe(time.Since(begin).Seconds())
 	}(time.Now())
 
-	return s.Service.BookNewCargo(origin, destination, arrivalDeadline)
+	return s.Service.BookNewCargo(origin, destination, deadline)
 }
 
 func (s *instrumentingService) LoadCargo(id cargo.TrackingID) (c Cargo, err error) {
diff --git a/examples/shipping/booking/logging.go b/examples/shipping/booking/logging.go
index 3a04576..931d430 100644
--- a/examples/shipping/booking/logging.go
+++ b/examples/shipping/booking/logging.go
@@ -3,9 +3,10 @@
 import (
 	"time"
 
+	"github.com/go-kit/kit/log"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
-	"github.com/go-kit/kit/log"
 )
 
 type loggingService struct {
@@ -18,18 +19,18 @@
 	return &loggingService{logger, s}
 }
 
-func (s *loggingService) BookNewCargo(origin location.UNLocode, destination location.UNLocode, arrivalDeadline time.Time) (id cargo.TrackingID, err error) {
+func (s *loggingService) BookNewCargo(origin location.UNLocode, destination location.UNLocode, deadline time.Time) (id cargo.TrackingID, err error) {
 	defer func(begin time.Time) {
 		s.logger.Log(
 			"method", "book",
 			"origin", origin,
 			"destination", destination,
-			"arrival_deadline", arrivalDeadline,
+			"arrival_deadline", deadline,
 			"took", time.Since(begin),
 			"err", err,
 		)
 	}(time.Now())
-	return s.Service.BookNewCargo(origin, destination, arrivalDeadline)
+	return s.Service.BookNewCargo(origin, destination, deadline)
 }
 
 func (s *loggingService) LoadCargo(id cargo.TrackingID) (c Cargo, err error) {
diff --git a/examples/shipping/booking/service.go b/examples/shipping/booking/service.go
index 47605f8..8689a5a 100644
--- a/examples/shipping/booking/service.go
+++ b/examples/shipping/booking/service.go
@@ -18,21 +18,21 @@
 type Service interface {
 	// BookNewCargo registers a new cargo in the tracking system, not yet
 	// routed.
-	BookNewCargo(origin location.UNLocode, destination location.UNLocode, arrivalDeadline time.Time) (cargo.TrackingID, error)
+	BookNewCargo(origin location.UNLocode, destination location.UNLocode, deadline time.Time) (cargo.TrackingID, error)
 
 	// LoadCargo returns a read model of a cargo.
-	LoadCargo(trackingID cargo.TrackingID) (Cargo, error)
+	LoadCargo(id cargo.TrackingID) (Cargo, error)
 
 	// RequestPossibleRoutesForCargo requests a list of itineraries describing
 	// possible routes for this cargo.
-	RequestPossibleRoutesForCargo(trackingID cargo.TrackingID) []cargo.Itinerary
+	RequestPossibleRoutesForCargo(id cargo.TrackingID) []cargo.Itinerary
 
 	// AssignCargoToRoute assigns a cargo to the route specified by the
 	// itinerary.
-	AssignCargoToRoute(trackingID cargo.TrackingID, itinerary cargo.Itinerary) error
+	AssignCargoToRoute(id cargo.TrackingID, itinerary cargo.Itinerary) error
 
 	// ChangeDestination changes the destination of a cargo.
-	ChangeDestination(trackingID cargo.TrackingID, unLocode location.UNLocode) error
+	ChangeDestination(id cargo.TrackingID, destination location.UNLocode) error
 
 	// Cargos returns a list of all cargos that have been booked.
 	Cargos() []Cargo
@@ -42,10 +42,10 @@
 }
 
 type service struct {
-	cargoRepository         cargo.Repository
-	locationRepository      location.Repository
-	routingService          routing.Service
-	handlingEventRepository cargo.HandlingEventRepository
+	cargos         cargo.Repository
+	locations      location.Repository
+	handlingEvents cargo.HandlingEventRepository
+	routingService routing.Service
 }
 
 func (s *service) AssignCargoToRoute(id cargo.TrackingID, itinerary cargo.Itinerary) error {
@@ -53,22 +53,18 @@
 		return ErrInvalidArgument
 	}
 
-	c, err := s.cargoRepository.Find(id)
+	c, err := s.cargos.Find(id)
 	if err != nil {
 		return err
 	}
 
 	c.AssignToRoute(itinerary)
 
-	if err := s.cargoRepository.Store(c); err != nil {
-		return err
-	}
-
-	return nil
+	return s.cargos.Store(c)
 }
 
-func (s *service) BookNewCargo(origin, destination location.UNLocode, arrivalDeadline time.Time) (cargo.TrackingID, error) {
-	if origin == "" || destination == "" || arrivalDeadline.IsZero() {
+func (s *service) BookNewCargo(origin, destination location.UNLocode, deadline time.Time) (cargo.TrackingID, error) {
+	if origin == "" || destination == "" || deadline.IsZero() {
 		return "", ErrInvalidArgument
 	}
 
@@ -76,29 +72,29 @@
 	rs := cargo.RouteSpecification{
 		Origin:          origin,
 		Destination:     destination,
-		ArrivalDeadline: arrivalDeadline,
+		ArrivalDeadline: deadline,
 	}
 
 	c := cargo.New(id, rs)
 
-	if err := s.cargoRepository.Store(c); err != nil {
+	if err := s.cargos.Store(c); err != nil {
 		return "", err
 	}
 
 	return c.TrackingID, nil
 }
 
-func (s *service) LoadCargo(trackingID cargo.TrackingID) (Cargo, error) {
-	if trackingID == "" {
+func (s *service) LoadCargo(id cargo.TrackingID) (Cargo, error) {
+	if id == "" {
 		return Cargo{}, ErrInvalidArgument
 	}
 
-	c, err := s.cargoRepository.Find(trackingID)
+	c, err := s.cargos.Find(id)
 	if err != nil {
 		return Cargo{}, err
 	}
 
-	return assemble(c, s.handlingEventRepository), nil
+	return assemble(c, s.handlingEvents), nil
 }
 
 func (s *service) ChangeDestination(id cargo.TrackingID, destination location.UNLocode) error {
@@ -106,12 +102,12 @@
 		return ErrInvalidArgument
 	}
 
-	c, err := s.cargoRepository.Find(id)
+	c, err := s.cargos.Find(id)
 	if err != nil {
 		return err
 	}
 
-	l, err := s.locationRepository.Find(destination)
+	l, err := s.locations.Find(destination)
 	if err != nil {
 		return err
 	}
@@ -122,7 +118,7 @@
 		ArrivalDeadline: c.RouteSpecification.ArrivalDeadline,
 	})
 
-	if err := s.cargoRepository.Store(c); err != nil {
+	if err := s.cargos.Store(c); err != nil {
 		return err
 	}
 
@@ -134,7 +130,7 @@
 		return nil
 	}
 
-	c, err := s.cargoRepository.Find(id)
+	c, err := s.cargos.Find(id)
 	if err != nil {
 		return []cargo.Itinerary{}
 	}
@@ -144,15 +140,15 @@
 
 func (s *service) Cargos() []Cargo {
 	var result []Cargo
-	for _, c := range s.cargoRepository.FindAll() {
-		result = append(result, assemble(c, s.handlingEventRepository))
+	for _, c := range s.cargos.FindAll() {
+		result = append(result, assemble(c, s.handlingEvents))
 	}
 	return result
 }
 
 func (s *service) Locations() []Location {
 	var result []Location
-	for _, v := range s.locationRepository.FindAll() {
+	for _, v := range s.locations.FindAll() {
 		result = append(result, Location{
 			UNLocode: string(v.UNLocode),
 			Name:     v.Name,
@@ -162,12 +158,12 @@
 }
 
 // NewService creates a booking service with necessary dependencies.
-func NewService(cr cargo.Repository, lr location.Repository, her cargo.HandlingEventRepository, rs routing.Service) Service {
+func NewService(cargos cargo.Repository, locations location.Repository, events cargo.HandlingEventRepository, rs routing.Service) Service {
 	return &service{
-		cargoRepository:         cr,
-		locationRepository:      lr,
-		handlingEventRepository: her,
-		routingService:          rs,
+		cargos:         cargos,
+		locations:      locations,
+		handlingEvents: events,
+		routingService: rs,
 	}
 }
 
@@ -188,7 +184,7 @@
 	TrackingID      string      `json:"tracking_id"`
 }
 
-func assemble(c *cargo.Cargo, her cargo.HandlingEventRepository) Cargo {
+func assemble(c *cargo.Cargo, events cargo.HandlingEventRepository) Cargo {
 	return Cargo{
 		TrackingID:      string(c.TrackingID),
 		Origin:          string(c.Origin),
diff --git a/examples/shipping/booking/transport.go b/examples/shipping/booking/transport.go
index 7cf5994..e445773 100644
--- a/examples/shipping/booking/transport.go
+++ b/examples/shipping/booking/transport.go
@@ -9,10 +9,11 @@
 	"github.com/gorilla/mux"
 	"golang.org/x/net/context"
 
+	kitlog "github.com/go-kit/kit/log"
+	kithttp "github.com/go-kit/kit/transport/http"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
-	kitlog "github.com/go-kit/kit/log"
-	kithttp "github.com/go-kit/kit/transport/http"
 )
 
 // MakeHandler returns a handler for the booking service.
@@ -81,7 +82,6 @@
 	r.Handle("/booking/v1/cargos/{id}/assign_to_route", assignToRouteHandler).Methods("POST")
 	r.Handle("/booking/v1/cargos/{id}/change_destination", changeDestinationHandler).Methods("POST")
 	r.Handle("/booking/v1/locations", listLocationsHandler).Methods("GET")
-	r.Handle("/booking/v1/docs", http.StripPrefix("/booking/v1/docs", http.FileServer(http.Dir("booking/docs"))))
 
 	return r
 }
diff --git a/examples/shipping/cargo/cargo.go b/examples/shipping/cargo/cargo.go
index d4bb5f4..a9440f5 100644
--- a/examples/shipping/cargo/cargo.go
+++ b/examples/shipping/cargo/cargo.go
@@ -57,7 +57,7 @@
 // Repository provides access a cargo store.
 type Repository interface {
 	Store(cargo *Cargo) error
-	Find(trackingID TrackingID) (*Cargo, error)
+	Find(id TrackingID) (*Cargo, error)
 	FindAll() []*Cargo
 }
 
diff --git a/examples/shipping/cargo/handling.go b/examples/shipping/cargo/handling.go
index 5f77bc4..bec8509 100644
--- a/examples/shipping/cargo/handling.go
+++ b/examples/shipping/cargo/handling.go
@@ -92,10 +92,10 @@
 }
 
 // CreateHandlingEvent creates a validated handling event.
-func (f *HandlingEventFactory) CreateHandlingEvent(registrationTime time.Time, completionTime time.Time, trackingID TrackingID,
+func (f *HandlingEventFactory) CreateHandlingEvent(registered time.Time, completed time.Time, id TrackingID,
 	voyageNumber voyage.Number, unLocode location.UNLocode, eventType HandlingEventType) (HandlingEvent, error) {
 
-	if _, err := f.CargoRepository.Find(trackingID); err != nil {
+	if _, err := f.CargoRepository.Find(id); err != nil {
 		return HandlingEvent{}, err
 	}
 
@@ -111,7 +111,7 @@
 	}
 
 	return HandlingEvent{
-		TrackingID: trackingID,
+		TrackingID: id,
 		Activity: HandlingActivity{
 			Type:         eventType,
 			Location:     unLocode,
diff --git a/examples/shipping/handling/endpoint.go b/examples/shipping/handling/endpoint.go
index e10bdda..0ee3f22 100644
--- a/examples/shipping/handling/endpoint.go
+++ b/examples/shipping/handling/endpoint.go
@@ -6,6 +6,7 @@
 	"golang.org/x/net/context"
 
 	"github.com/go-kit/kit/endpoint"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
 	"github.com/go-kit/kit/examples/shipping/voyage"
diff --git a/examples/shipping/handling/instrumenting.go b/examples/shipping/handling/instrumenting.go
index 065eca6..fecce04 100644
--- a/examples/shipping/handling/instrumenting.go
+++ b/examples/shipping/handling/instrumenting.go
@@ -17,15 +17,15 @@
 }
 
 // NewInstrumentingService returns an instance of an instrumenting Service.
-func NewInstrumentingService(requestCount metrics.Counter, requestLatency metrics.Histogram, s Service) Service {
+func NewInstrumentingService(counter metrics.Counter, latency metrics.Histogram, s Service) Service {
 	return &instrumentingService{
-		requestCount:   requestCount,
-		requestLatency: requestLatency,
+		requestCount:   counter,
+		requestLatency: latency,
 		Service:        s,
 	}
 }
 
-func (s *instrumentingService) RegisterHandlingEvent(completionTime time.Time, trackingID cargo.TrackingID, voyage voyage.Number,
+func (s *instrumentingService) RegisterHandlingEvent(completed time.Time, id cargo.TrackingID, voyageNumber voyage.Number,
 	loc location.UNLocode, eventType cargo.HandlingEventType) error {
 
 	defer func(begin time.Time) {
@@ -33,5 +33,5 @@
 		s.requestLatency.With("method", "register_incident").Observe(time.Since(begin).Seconds())
 	}(time.Now())
 
-	return s.Service.RegisterHandlingEvent(completionTime, trackingID, voyage, loc, eventType)
+	return s.Service.RegisterHandlingEvent(completed, id, voyageNumber, loc, eventType)
 }
diff --git a/examples/shipping/handling/logging.go b/examples/shipping/handling/logging.go
index 26457ac..84722fb 100644
--- a/examples/shipping/handling/logging.go
+++ b/examples/shipping/handling/logging.go
@@ -3,10 +3,11 @@
 import (
 	"time"
 
+	"github.com/go-kit/kit/log"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
 	"github.com/go-kit/kit/examples/shipping/voyage"
-	"github.com/go-kit/kit/log"
 )
 
 type loggingService struct {
@@ -19,19 +20,19 @@
 	return &loggingService{logger, s}
 }
 
-func (s *loggingService) RegisterHandlingEvent(completionTime time.Time, trackingID cargo.TrackingID, voyageNumber voyage.Number,
+func (s *loggingService) RegisterHandlingEvent(completed time.Time, id cargo.TrackingID, voyageNumber voyage.Number,
 	unLocode location.UNLocode, eventType cargo.HandlingEventType) (err error) {
 	defer func(begin time.Time) {
 		s.logger.Log(
 			"method", "register_incident",
-			"tracking_id", trackingID,
+			"tracking_id", id,
 			"location", unLocode,
 			"voyage", voyageNumber,
 			"event_type", eventType,
-			"completion_time", completionTime,
+			"completion_time", completed,
 			"took", time.Since(begin),
 			"err", err,
 		)
 	}(time.Now())
-	return s.Service.RegisterHandlingEvent(completionTime, trackingID, voyageNumber, unLocode, eventType)
+	return s.Service.RegisterHandlingEvent(completed, id, voyageNumber, unLocode, eventType)
 }
diff --git a/examples/shipping/handling/service.go b/examples/shipping/handling/service.go
index f548f4c..83d503a 100644
--- a/examples/shipping/handling/service.go
+++ b/examples/shipping/handling/service.go
@@ -24,7 +24,7 @@
 type Service interface {
 	// RegisterHandlingEvent registers a handling event in the system, and
 	// notifies interested parties that a cargo has been handled.
-	RegisterHandlingEvent(completionTime time.Time, trackingID cargo.TrackingID, voyageNumber voyage.Number,
+	RegisterHandlingEvent(completed time.Time, id cargo.TrackingID, voyageNumber voyage.Number,
 		unLocode location.UNLocode, eventType cargo.HandlingEventType) error
 }
 
@@ -34,13 +34,13 @@
 	handlingEventHandler    EventHandler
 }
 
-func (s *service) RegisterHandlingEvent(completionTime time.Time, trackingID cargo.TrackingID, voyage voyage.Number,
+func (s *service) RegisterHandlingEvent(completed time.Time, id cargo.TrackingID, voyageNumber voyage.Number,
 	loc location.UNLocode, eventType cargo.HandlingEventType) error {
-	if completionTime.IsZero() || trackingID == "" || loc == "" || eventType == cargo.NotHandled {
+	if completed.IsZero() || id == "" || loc == "" || eventType == cargo.NotHandled {
 		return ErrInvalidArgument
 	}
 
-	e, err := s.handlingEventFactory.CreateHandlingEvent(time.Now(), completionTime, trackingID, voyage, loc, eventType)
+	e, err := s.handlingEventFactory.CreateHandlingEvent(time.Now(), completed, id, voyageNumber, loc, eventType)
 	if err != nil {
 		return err
 	}
diff --git a/examples/shipping/handling/transport.go b/examples/shipping/handling/transport.go
index 1777ad6..e5d2c44 100644
--- a/examples/shipping/handling/transport.go
+++ b/examples/shipping/handling/transport.go
@@ -8,11 +8,12 @@
 	"github.com/gorilla/mux"
 	"golang.org/x/net/context"
 
+	kitlog "github.com/go-kit/kit/log"
+	kithttp "github.com/go-kit/kit/transport/http"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
 	"github.com/go-kit/kit/examples/shipping/voyage"
-	kitlog "github.com/go-kit/kit/log"
-	kithttp "github.com/go-kit/kit/transport/http"
 )
 
 // MakeHandler returns a handler for the handling service.
diff --git a/examples/shipping/inmem/inmem.go b/examples/shipping/inmem/inmem.go
new file mode 100644
index 0000000..f941b7e
--- /dev/null
+++ b/examples/shipping/inmem/inmem.go
@@ -0,0 +1,142 @@
+// Package inmem provides in-memory implementations of all the domain repositories.
+package inmem
+
+import (
+	"sync"
+
+	"github.com/go-kit/kit/examples/shipping/cargo"
+	"github.com/go-kit/kit/examples/shipping/location"
+	"github.com/go-kit/kit/examples/shipping/voyage"
+)
+
+type cargoRepository struct {
+	mtx    sync.RWMutex
+	cargos map[cargo.TrackingID]*cargo.Cargo
+}
+
+func (r *cargoRepository) Store(c *cargo.Cargo) error {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	r.cargos[c.TrackingID] = c
+	return nil
+}
+
+func (r *cargoRepository) Find(id cargo.TrackingID) (*cargo.Cargo, error) {
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	if val, ok := r.cargos[id]; ok {
+		return val, nil
+	}
+	return nil, cargo.ErrUnknown
+}
+
+func (r *cargoRepository) FindAll() []*cargo.Cargo {
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	c := make([]*cargo.Cargo, 0, len(r.cargos))
+	for _, val := range r.cargos {
+		c = append(c, val)
+	}
+	return c
+}
+
+// NewCargoRepository returns a new instance of a in-memory cargo repository.
+func NewCargoRepository() cargo.Repository {
+	return &cargoRepository{
+		cargos: make(map[cargo.TrackingID]*cargo.Cargo),
+	}
+}
+
+type locationRepository struct {
+	locations map[location.UNLocode]*location.Location
+}
+
+func (r *locationRepository) Find(locode location.UNLocode) (*location.Location, error) {
+	if l, ok := r.locations[locode]; ok {
+		return l, nil
+	}
+	return nil, location.ErrUnknown
+}
+
+func (r *locationRepository) FindAll() []*location.Location {
+	l := make([]*location.Location, 0, len(r.locations))
+	for _, val := range r.locations {
+		l = append(l, val)
+	}
+	return l
+}
+
+// NewLocationRepository returns a new instance of a in-memory location repository.
+func NewLocationRepository() location.Repository {
+	r := &locationRepository{
+		locations: make(map[location.UNLocode]*location.Location),
+	}
+
+	r.locations[location.SESTO] = location.Stockholm
+	r.locations[location.AUMEL] = location.Melbourne
+	r.locations[location.CNHKG] = location.Hongkong
+	r.locations[location.JNTKO] = location.Tokyo
+	r.locations[location.NLRTM] = location.Rotterdam
+	r.locations[location.DEHAM] = location.Hamburg
+
+	return r
+}
+
+type voyageRepository struct {
+	voyages map[voyage.Number]*voyage.Voyage
+}
+
+func (r *voyageRepository) Find(voyageNumber voyage.Number) (*voyage.Voyage, error) {
+	if v, ok := r.voyages[voyageNumber]; ok {
+		return v, nil
+	}
+
+	return nil, voyage.ErrUnknown
+}
+
+// NewVoyageRepository returns a new instance of a in-memory voyage repository.
+func NewVoyageRepository() voyage.Repository {
+	r := &voyageRepository{
+		voyages: make(map[voyage.Number]*voyage.Voyage),
+	}
+
+	r.voyages[voyage.V100.Number] = voyage.V100
+	r.voyages[voyage.V300.Number] = voyage.V300
+	r.voyages[voyage.V400.Number] = voyage.V400
+
+	r.voyages[voyage.V0100S.Number] = voyage.V0100S
+	r.voyages[voyage.V0200T.Number] = voyage.V0200T
+	r.voyages[voyage.V0300A.Number] = voyage.V0300A
+	r.voyages[voyage.V0301S.Number] = voyage.V0301S
+	r.voyages[voyage.V0400S.Number] = voyage.V0400S
+
+	return r
+}
+
+type handlingEventRepository struct {
+	mtx    sync.RWMutex
+	events map[cargo.TrackingID][]cargo.HandlingEvent
+}
+
+func (r *handlingEventRepository) Store(e cargo.HandlingEvent) {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	// Make array if it's the first event with this tracking ID.
+	if _, ok := r.events[e.TrackingID]; !ok {
+		r.events[e.TrackingID] = make([]cargo.HandlingEvent, 0)
+	}
+	r.events[e.TrackingID] = append(r.events[e.TrackingID], e)
+}
+
+func (r *handlingEventRepository) QueryHandlingHistory(id cargo.TrackingID) cargo.HandlingHistory {
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	return cargo.HandlingHistory{HandlingEvents: r.events[id]}
+}
+
+// NewHandlingEventRepository returns a new instance of a in-memory handling event repository.
+func NewHandlingEventRepository() cargo.HandlingEventRepository {
+	return &handlingEventRepository{
+		events: make(map[cargo.TrackingID][]cargo.HandlingEvent),
+	}
+}
diff --git a/examples/shipping/inspection/inspection.go b/examples/shipping/inspection/inspection.go
index a3f7147..91cceb0 100644
--- a/examples/shipping/inspection/inspection.go
+++ b/examples/shipping/inspection/inspection.go
@@ -14,38 +14,38 @@
 	// InspectCargo inspects cargo and send relevant notifications to
 	// interested parties, for example if a cargo has been misdirected, or
 	// unloaded at the final destination.
-	InspectCargo(trackingID cargo.TrackingID)
+	InspectCargo(id cargo.TrackingID)
 }
 
 type service struct {
-	cargoRepository         cargo.Repository
-	handlingEventRepository cargo.HandlingEventRepository
-	cargoEventHandler       EventHandler
+	cargos  cargo.Repository
+	events  cargo.HandlingEventRepository
+	handler EventHandler
 }
 
 // TODO: Should be transactional
-func (s *service) InspectCargo(trackingID cargo.TrackingID) {
-	c, err := s.cargoRepository.Find(trackingID)
+func (s *service) InspectCargo(id cargo.TrackingID) {
+	c, err := s.cargos.Find(id)
 	if err != nil {
 		return
 	}
 
-	h := s.handlingEventRepository.QueryHandlingHistory(trackingID)
+	h := s.events.QueryHandlingHistory(id)
 
 	c.DeriveDeliveryProgress(h)
 
 	if c.Delivery.IsMisdirected {
-		s.cargoEventHandler.CargoWasMisdirected(c)
+		s.handler.CargoWasMisdirected(c)
 	}
 
 	if c.Delivery.IsUnloadedAtDestination {
-		s.cargoEventHandler.CargoHasArrived(c)
+		s.handler.CargoHasArrived(c)
 	}
 
-	s.cargoRepository.Store(c)
+	s.cargos.Store(c)
 }
 
 // NewService creates a inspection service with necessary dependencies.
-func NewService(cargoRepository cargo.Repository, handlingEventRepository cargo.HandlingEventRepository, eventHandler EventHandler) Service {
-	return &service{cargoRepository, handlingEventRepository, eventHandler}
+func NewService(cargos cargo.Repository, events cargo.HandlingEventRepository, handler EventHandler) Service {
+	return &service{cargos, events, handler}
 }
diff --git a/examples/shipping/location/location.go b/examples/shipping/location/location.go
index 5129380..4a9d2f9 100644
--- a/examples/shipping/location/location.go
+++ b/examples/shipping/location/location.go
@@ -22,6 +22,6 @@
 
 // Repository provides access a location store.
 type Repository interface {
-	Find(locode UNLocode) (Location, error)
-	FindAll() []Location
+	Find(locode UNLocode) (*Location, error)
+	FindAll() []*Location
 }
diff --git a/examples/shipping/location/sample_locations.go b/examples/shipping/location/sample_locations.go
index de0d4c1..7fd34ef 100644
--- a/examples/shipping/location/sample_locations.go
+++ b/examples/shipping/location/sample_locations.go
@@ -15,13 +15,13 @@
 
 // Sample locations.
 var (
-	Stockholm = Location{SESTO, "Stockholm"}
-	Melbourne = Location{AUMEL, "Melbourne"}
-	Hongkong  = Location{CNHKG, "Hongkong"}
-	NewYork   = Location{USNYC, "New York"}
-	Chicago   = Location{USCHI, "Chicago"}
-	Tokyo     = Location{JNTKO, "Tokyo"}
-	Hamburg   = Location{DEHAM, "Hamburg"}
-	Rotterdam = Location{NLRTM, "Rotterdam"}
-	Helsinki  = Location{FIHEL, "Helsinki"}
+	Stockholm = &Location{SESTO, "Stockholm"}
+	Melbourne = &Location{AUMEL, "Melbourne"}
+	Hongkong  = &Location{CNHKG, "Hongkong"}
+	NewYork   = &Location{USNYC, "New York"}
+	Chicago   = &Location{USCHI, "Chicago"}
+	Tokyo     = &Location{JNTKO, "Tokyo"}
+	Hamburg   = &Location{DEHAM, "Hamburg"}
+	Rotterdam = &Location{NLRTM, "Rotterdam"}
+	Helsinki  = &Location{FIHEL, "Helsinki"}
 )
diff --git a/examples/shipping/main.go b/examples/shipping/main.go
index 3800cf1..4fbcd94 100644
--- a/examples/shipping/main.go
+++ b/examples/shipping/main.go
@@ -19,9 +19,9 @@
 	"github.com/go-kit/kit/examples/shipping/booking"
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/handling"
+	"github.com/go-kit/kit/examples/shipping/inmem"
 	"github.com/go-kit/kit/examples/shipping/inspection"
 	"github.com/go-kit/kit/examples/shipping/location"
-	"github.com/go-kit/kit/examples/shipping/repository"
 	"github.com/go-kit/kit/examples/shipping/routing"
 	"github.com/go-kit/kit/examples/shipping/tracking"
 )
@@ -50,10 +50,10 @@
 	logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
 
 	var (
-		cargos         = repository.NewCargo()
-		locations      = repository.NewLocation()
-		voyages        = repository.NewVoyage()
-		handlingEvents = repository.NewHandlingEvent()
+		cargos         = inmem.NewCargoRepository()
+		locations      = inmem.NewLocationRepository()
+		voyages        = inmem.NewVoyageRepository()
+		handlingEvents = inmem.NewHandlingEventRepository()
 	)
 
 	// Configure some questionable dependencies.
@@ -74,7 +74,7 @@
 	fieldKeys := []string{"method"}
 
 	var rs routing.Service
-	rs = routing.NewProxyingMiddleware(*routingServiceURL, ctx)(rs)
+	rs = routing.NewProxyingMiddleware(ctx, *routingServiceURL)(rs)
 
 	var bs booking.Service
 	bs = booking.NewService(cargos, locations, handlingEvents, rs)
@@ -186,14 +186,18 @@
 		Destination:     location.SESTO,
 		ArrivalDeadline: time.Now().AddDate(0, 0, 7),
 	})
-	_ = r.Store(test1)
+	if err := r.Store(test1); err != nil {
+		panic(err)
+	}
 
 	test2 := cargo.New("ABC123", cargo.RouteSpecification{
 		Origin:          location.SESTO,
 		Destination:     location.CNHKG,
 		ArrivalDeadline: time.Now().AddDate(0, 0, 14),
 	})
-	_ = r.Store(test2)
+	if err := r.Store(test2); err != nil {
+		panic(err)
+	}
 }
 
 type serializedLogger struct {
diff --git a/examples/shipping/mock/mock.go b/examples/shipping/mock/mock.go
new file mode 100644
index 0000000..04d60da
--- /dev/null
+++ b/examples/shipping/mock/mock.go
@@ -0,0 +1,103 @@
+package mock
+
+import (
+	"github.com/go-kit/kit/examples/shipping/cargo"
+	"github.com/go-kit/kit/examples/shipping/location"
+	"github.com/go-kit/kit/examples/shipping/voyage"
+)
+
+// CargoRepository is a mock cargo repository.
+type CargoRepository struct {
+	StoreFn      func(c *cargo.Cargo) error
+	StoreInvoked bool
+
+	FindFn      func(id cargo.TrackingID) (*cargo.Cargo, error)
+	FindInvoked bool
+
+	FindAllFn      func() []*cargo.Cargo
+	FindAllInvoked bool
+}
+
+// Store calls the StoreFn.
+func (r *CargoRepository) Store(c *cargo.Cargo) error {
+	r.StoreInvoked = true
+	return r.StoreFn(c)
+}
+
+// Find calls the FindFn.
+func (r *CargoRepository) Find(id cargo.TrackingID) (*cargo.Cargo, error) {
+	r.FindInvoked = true
+	return r.FindFn(id)
+}
+
+// FindAll calls the FindAllFn.
+func (r *CargoRepository) FindAll() []*cargo.Cargo {
+	r.FindAllInvoked = true
+	return r.FindAllFn()
+}
+
+// LocationRepository is a mock location repository.
+type LocationRepository struct {
+	FindFn      func(location.UNLocode) (*location.Location, error)
+	FindInvoked bool
+
+	FindAllFn      func() []*location.Location
+	FindAllInvoked bool
+}
+
+// Find calls the FindFn.
+func (r *LocationRepository) Find(locode location.UNLocode) (*location.Location, error) {
+	r.FindInvoked = true
+	return r.FindFn(locode)
+}
+
+// FindAll calls the FindAllFn.
+func (r *LocationRepository) FindAll() []*location.Location {
+	r.FindAllInvoked = true
+	return r.FindAllFn()
+}
+
+// VoyageRepository is a mock voyage repository.
+type VoyageRepository struct {
+	FindFn      func(voyage.Number) (*voyage.Voyage, error)
+	FindInvoked bool
+}
+
+// Find calls the FindFn.
+func (r *VoyageRepository) Find(number voyage.Number) (*voyage.Voyage, error) {
+	r.FindInvoked = true
+	return r.FindFn(number)
+}
+
+// HandlingEventRepository is a mock handling events repository.
+type HandlingEventRepository struct {
+	StoreFn      func(cargo.HandlingEvent)
+	StoreInvoked bool
+
+	QueryHandlingHistoryFn      func(cargo.TrackingID) cargo.HandlingHistory
+	QueryHandlingHistoryInvoked bool
+}
+
+// Store calls the StoreFn.
+func (r *HandlingEventRepository) Store(e cargo.HandlingEvent) {
+	r.StoreInvoked = true
+	r.StoreFn(e)
+}
+
+// QueryHandlingHistory calls the QueryHandlingHistoryFn.
+func (r *HandlingEventRepository) QueryHandlingHistory(id cargo.TrackingID) cargo.HandlingHistory {
+	r.QueryHandlingHistoryInvoked = true
+	return r.QueryHandlingHistoryFn(id)
+}
+
+// RoutingService provides a mock routing service.
+type RoutingService struct {
+	FetchRoutesFn      func(cargo.RouteSpecification) []cargo.Itinerary
+	FetchRoutesInvoked bool
+}
+
+// FetchRoutesForSpecification calls the FetchRoutesFn.
+func (s *RoutingService) FetchRoutesForSpecification(rs cargo.RouteSpecification) []cargo.Itinerary {
+	s.FetchRoutesInvoked = true
+	return s.FetchRoutesFn(rs)
+}
diff --git a/examples/shipping/repository/repositories.go b/examples/shipping/repository/repositories.go
deleted file mode 100644
index 714d0a8..0000000
--- a/examples/shipping/repository/repositories.go
+++ /dev/null
@@ -1,142 +0,0 @@
-// Package repository provides implementations of all the domain repositories.
-package repository
-
-import (
-	"sync"
-
-	"github.com/go-kit/kit/examples/shipping/cargo"
-	"github.com/go-kit/kit/examples/shipping/location"
-	"github.com/go-kit/kit/examples/shipping/voyage"
-)
-
-type cargoRepository struct {
-	mtx    sync.RWMutex
-	cargos map[cargo.TrackingID]*cargo.Cargo
-}
-
-func (r *cargoRepository) Store(c *cargo.Cargo) error {
-	r.mtx.Lock()
-	defer r.mtx.Unlock()
-	r.cargos[c.TrackingID] = c
-	return nil
-}
-
-func (r *cargoRepository) Find(trackingID cargo.TrackingID) (*cargo.Cargo, error) {
-	r.mtx.RLock()
-	defer r.mtx.RUnlock()
-	if val, ok := r.cargos[trackingID]; ok {
-		return val, nil
-	}
-	return nil, cargo.ErrUnknown
-}
-
-func (r *cargoRepository) FindAll() []*cargo.Cargo {
-	r.mtx.RLock()
-	defer r.mtx.RUnlock()
-	c := make([]*cargo.Cargo, 0, len(r.cargos))
-	for _, val := range r.cargos {
-		c = append(c, val)
-	}
-	return c
-}
-
-// NewCargo returns a new instance of a in-memory cargo repository.
-func NewCargo() cargo.Repository {
-	return &cargoRepository{
-		cargos: make(map[cargo.TrackingID]*cargo.Cargo),
-	}
-}
-
-type locationRepository struct {
-	locations map[location.UNLocode]location.Location
-}
-
-func (r *locationRepository) Find(locode location.UNLocode) (location.Location, error) {
-	if l, ok := r.locations[locode]; ok {
-		return l, nil
-	}
-	return location.Location{}, location.ErrUnknown
-}
-
-func (r *locationRepository) FindAll() []location.Location {
-	l := make([]location.Location, 0, len(r.locations))
-	for _, val := range r.locations {
-		l = append(l, val)
-	}
-	return l
-}
-
-// NewLocation returns a new instance of a in-memory location repository.
-func NewLocation() location.Repository {
-	r := &locationRepository{
-		locations: make(map[location.UNLocode]location.Location),
-	}
-
-	r.locations[location.SESTO] = location.Stockholm
-	r.locations[location.AUMEL] = location.Melbourne
-	r.locations[location.CNHKG] = location.Hongkong
-	r.locations[location.JNTKO] = location.Tokyo
-	r.locations[location.NLRTM] = location.Rotterdam
-	r.locations[location.DEHAM] = location.Hamburg
-
-	return r
-}
-
-type voyageRepository struct {
-	voyages map[voyage.Number]*voyage.Voyage
-}
-
-func (r *voyageRepository) Find(voyageNumber voyage.Number) (*voyage.Voyage, error) {
-	if v, ok := r.voyages[voyageNumber]; ok {
-		return v, nil
-	}
-
-	return nil, voyage.ErrUnknown
-}
-
-// NewVoyage returns a new instance of a in-memory voyage repository.
-func NewVoyage() voyage.Repository {
-	r := &voyageRepository{
-		voyages: make(map[voyage.Number]*voyage.Voyage),
-	}
-
-	r.voyages[voyage.V100.Number] = voyage.V100
-	r.voyages[voyage.V300.Number] = voyage.V300
-	r.voyages[voyage.V400.Number] = voyage.V400
-
-	r.voyages[voyage.V0100S.Number] = voyage.V0100S
-	r.voyages[voyage.V0200T.Number] = voyage.V0200T
-	r.voyages[voyage.V0300A.Number] = voyage.V0300A
-	r.voyages[voyage.V0301S.Number] = voyage.V0301S
-	r.voyages[voyage.V0400S.Number] = voyage.V0400S
-
-	return r
-}
-
-type handlingEventRepository struct {
-	mtx    sync.RWMutex
-	events map[cargo.TrackingID][]cargo.HandlingEvent
-}
-
-func (r *handlingEventRepository) Store(e cargo.HandlingEvent) {
-	r.mtx.Lock()
-	defer r.mtx.Unlock()
-	// Make array if it's the first event with this tracking ID.
-	if _, ok := r.events[e.TrackingID]; !ok {
-		r.events[e.TrackingID] = make([]cargo.HandlingEvent, 0)
-	}
-	r.events[e.TrackingID] = append(r.events[e.TrackingID], e)
-}
-
-func (r *handlingEventRepository) QueryHandlingHistory(trackingID cargo.TrackingID) cargo.HandlingHistory {
-	r.mtx.RLock()
-	defer r.mtx.RUnlock()
-	return cargo.HandlingHistory{HandlingEvents: r.events[trackingID]}
-}
-
-// NewHandlingEvent returns a new instance of a in-memory handling event repository.
-func NewHandlingEvent() cargo.HandlingEventRepository {
-	return &handlingEventRepository{
-		events: make(map[cargo.TrackingID][]cargo.HandlingEvent),
-	}
-}
diff --git a/examples/shipping/routing/proxying.go b/examples/shipping/routing/proxying.go
index 3051caf..a53f265 100644
--- a/examples/shipping/routing/proxying.go
+++ b/examples/shipping/routing/proxying.go
@@ -10,10 +10,11 @@
 
 	"github.com/go-kit/kit/circuitbreaker"
 	"github.com/go-kit/kit/endpoint"
+	kithttp "github.com/go-kit/kit/transport/http"
+
 	"github.com/go-kit/kit/examples/shipping/cargo"
 	"github.com/go-kit/kit/examples/shipping/location"
 	"github.com/go-kit/kit/examples/shipping/voyage"
-	kithttp "github.com/go-kit/kit/transport/http"
 )
 
 type proxyService struct {
@@ -56,7 +57,7 @@
 type ServiceMiddleware func(Service) Service
 
 // NewProxyingMiddleware returns a new instance of a proxying middleware.
-func NewProxyingMiddleware(proxyURL string, ctx context.Context) ServiceMiddleware {
+func NewProxyingMiddleware(ctx context.Context, proxyURL string) ServiceMiddleware {
 	return func(next Service) Service {
 		var e endpoint.Endpoint
 		e = makeFetchRoutesEndpoint(ctx, proxyURL)
diff --git a/examples/shipping/tracking/instrumenting.go b/examples/shipping/tracking/instrumenting.go
index c2016d2..f5dc018 100644
--- a/examples/shipping/tracking/instrumenting.go
+++ b/examples/shipping/tracking/instrumenting.go
@@ -13,10 +13,10 @@
 }
 
 // NewInstrumentingService returns an instance of an instrumenting Service.
-func NewInstrumentingService(requestCount metrics.Counter, requestLatency metrics.Histogram, s Service) Service {
+func NewInstrumentingService(counter metrics.Counter, latency metrics.Histogram, s Service) Service {
 	return &instrumentingService{
-		requestCount:   requestCount,
-		requestLatency: requestLatency,
+		requestCount:   counter,
+		requestLatency: latency,
 		Service:        s,
 	}
 }
diff --git a/examples/shipping/tracking/service.go b/examples/shipping/tracking/service.go
index d5b9273..b0e360b 100644
--- a/examples/shipping/tracking/service.go
+++ b/examples/shipping/tracking/service.go
@@ -37,10 +37,10 @@
 }
 
 // NewService returns a new instance of the default Service.
-func NewService(cargos cargo.Repository, handlingEvents cargo.HandlingEventRepository) Service {
+func NewService(cargos cargo.Repository, events cargo.HandlingEventRepository) Service {
 	return &service{
 		cargos:         cargos,
-		handlingEvents: handlingEvents,
+		handlingEvents: events,
 	}
 }
 
@@ -71,7 +71,7 @@
 	Expected    bool   `json:"expected"`
 }
 
-func assemble(c *cargo.Cargo, her cargo.HandlingEventRepository) Cargo {
+func assemble(c *cargo.Cargo, events cargo.HandlingEventRepository) Cargo {
 	return Cargo{
 		TrackingID:           string(c.TrackingID),
 		Origin:               string(c.Origin),
@@ -80,7 +80,7 @@
 		NextExpectedActivity: nextExpectedActivity(c),
 		ArrivalDeadline:      c.RouteSpecification.ArrivalDeadline,
 		StatusText:           assembleStatusText(c),
-		Events:               assembleEvents(c, her),
+		Events:               assembleEvents(c, events),
 	}
 }
 
@@ -129,8 +129,8 @@
 	}
 }
 
-func assembleEvents(c *cargo.Cargo, r cargo.HandlingEventRepository) []Event {
-	h := r.QueryHandlingHistory(c.TrackingID)
+func assembleEvents(c *cargo.Cargo, handlingEvents cargo.HandlingEventRepository) []Event {
+	h := handlingEvents.QueryHandlingHistory(c.TrackingID)
 
 	var events []Event
 	for _, e := range h.HandlingEvents {
diff --git a/examples/shipping/tracking/transport.go b/examples/shipping/tracking/transport.go
index 9cac1ec..3cdb9b1 100644
--- a/examples/shipping/tracking/transport.go
+++ b/examples/shipping/tracking/transport.go
@@ -8,9 +8,10 @@
 	"github.com/gorilla/mux"
 	"golang.org/x/net/context"
 
-	"github.com/go-kit/kit/examples/shipping/cargo"
 	kitlog "github.com/go-kit/kit/log"
 	kithttp "github.com/go-kit/kit/transport/http"
+
+	"github.com/go-kit/kit/examples/shipping/cargo"
 )
 
 // MakeHandler returns a handler for the tracking service.
diff --git a/examples/shipping/voyage/sample_voyages.go b/examples/shipping/voyage/sample_voyages.go
index 51b7a05..751f588 100644
--- a/examples/shipping/voyage/sample_voyages.go
+++ b/examples/shipping/voyage/sample_voyages.go
@@ -6,25 +6,25 @@
 var (
 	V100 = New("V100", Schedule{
 		[]CarrierMovement{
-			{DepartureLocation: location.Hongkong, ArrivalLocation: location.Tokyo},
-			{DepartureLocation: location.Tokyo, ArrivalLocation: location.NewYork},
+			{DepartureLocation: location.CNHKG, ArrivalLocation: location.JNTKO},
+			{DepartureLocation: location.JNTKO, ArrivalLocation: location.USNYC},
 		},
 	})
 
 	V300 = New("V300", Schedule{
 		[]CarrierMovement{
-			{DepartureLocation: location.Tokyo, ArrivalLocation: location.Rotterdam},
-			{DepartureLocation: location.Rotterdam, ArrivalLocation: location.Hamburg},
-			{DepartureLocation: location.Hamburg, ArrivalLocation: location.Melbourne},
-			{DepartureLocation: location.Melbourne, ArrivalLocation: location.Tokyo},
+			{DepartureLocation: location.JNTKO, ArrivalLocation: location.NLRTM},
+			{DepartureLocation: location.NLRTM, ArrivalLocation: location.DEHAM},
+			{DepartureLocation: location.DEHAM, ArrivalLocation: location.AUMEL},
+			{DepartureLocation: location.AUMEL, ArrivalLocation: location.JNTKO},
 		},
 	})
 
 	V400 = New("V400", Schedule{
 		[]CarrierMovement{
-			{DepartureLocation: location.Hamburg, ArrivalLocation: location.Stockholm},
-			{DepartureLocation: location.Stockholm, ArrivalLocation: location.Helsinki},
-			{DepartureLocation: location.Helsinki, ArrivalLocation: location.Hamburg},
+			{DepartureLocation: location.DEHAM, ArrivalLocation: location.SESTO},
+			{DepartureLocation: location.SESTO, ArrivalLocation: location.FIHEL},
+			{DepartureLocation: location.FIHEL, ArrivalLocation: location.DEHAM},
 		},
 	})
 )
diff --git a/examples/shipping/voyage/voyage.go b/examples/shipping/voyage/voyage.go
index 57a70b0..37366af 100644
--- a/examples/shipping/voyage/voyage.go
+++ b/examples/shipping/voyage/voyage.go
@@ -29,8 +29,8 @@
 
 // CarrierMovement is a vessel voyage from one location to another.
 type CarrierMovement struct {
-	DepartureLocation location.Location
-	ArrivalLocation   location.Location
+	DepartureLocation location.UNLocode
+	ArrivalLocation   location.UNLocode
 	DepartureTime     time.Time
 	ArrivalTime       time.Time
 }