diff --git a/api/errors/descriptors.go b/api/errors/descriptors.go
new file mode 100644
index 00000000..e3dfd37b
--- /dev/null
+++ b/api/errors/descriptors.go
@@ -0,0 +1,135 @@
+package errors
+
+import "net/http"
+
+// ErrorDescriptor provides relevant information about a given error code.
+type ErrorDescriptor struct {
+	// Code is the error code that this descriptor describes.
+	Code ErrorCode
+
+	// Value provides a unique, string key, often captilized with
+	// underscores, to identify the error code. This value is used as the
+	// keyed value when serializing api errors.
+	Value string
+
+	// Message is a short, human readable decription of the error condition
+	// included in API responses.
+	Message string
+
+	// Description provides a complete account of the errors purpose, suitable
+	// for use in documentation.
+	Description string
+
+	// DefaultStatusCode should to be returned via the HTTP API. Some error
+	// may have different status codes depending on the situation.
+	DefaultStatusCode int
+}
+
+var descriptors = []ErrorDescriptor{
+	{
+		Code:    ErrorCodeUnknown,
+		Value:   "UNKNOWN",
+		Message: "unknown error",
+	},
+	{
+		Code:    ErrorCodeDigestInvalid,
+		Value:   "DIGEST_INVALID",
+		Message: "provided digest did not match uploaded content",
+		Description: `When a blob is uploaded, the registry will check that
+		the content matches the digest provided by the client. The error may
+		include a detail structure with the key "digest", including the
+		invalid digest string. This error may also be returned when a manifest
+		includes an invalid layer digest.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeSizeInvalid,
+		Value:   "SIZE_INVALID",
+		Message: "provided length did not match content length",
+		Description: `When a layer is uploaded, the provided size will be
+		checked against the uploaded content. If they do not match, this error
+		will be returned.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeNameInvalid,
+		Value:   "NAME_INVALID",
+		Message: "manifest name did not match URI",
+		Description: `During a manifest upload, if the name in the manifest
+		does not match the uri name, this error will be returned.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeTagInvalid,
+		Value:   "TAG_INVALID",
+		Message: "manifest tag did not match URI",
+		Description: `During a manifest upload, if the tag in the manifest
+		does not match the uri tag, this error will be returned.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeNameUnknown,
+		Value:   "NAME_UNKNOWN",
+		Message: "repository name not known to registry",
+		Description: `This is returned if the name used during an operation is
+		unknown to the registry.`,
+		DefaultStatusCode: http.StatusNotFound,
+	},
+	{
+		Code:    ErrorCodeManifestUnknown,
+		Value:   "MANIFEST_UNKNOWN",
+		Message: "manifest unknown",
+		Description: `This error is returned when the manifest, identified by
+		name and tag is unknown to the repository.`,
+		DefaultStatusCode: http.StatusNotFound,
+	},
+	{
+		Code:    ErrorCodeManifestInvalid,
+		Value:   "MANIFEST_INVALID",
+		Message: "manifest invalid",
+		Description: `During upload, manifests undergo several checks ensuring
+		validity. If those checks fail, this error may be returned, unless a
+		more specific error is included.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeManifestUnverified,
+		Value:   "MANIFEST_UNVERIFIED",
+		Message: "manifest failed signature verification",
+		Description: `During manifest upload, if the manifest fails signature
+		verification, this error will be returned.`,
+		DefaultStatusCode: http.StatusBadRequest,
+	},
+	{
+		Code:    ErrorCodeBlobUnknown,
+		Value:   "BLOB_UNKNOWN",
+		Message: "blob unknown to registry",
+		Description: `This error may be returned when a blob is unknown to the
+		registry in a specified repository. This can be returned with a
+		standard get or if a manifest references an unknown layer during
+		upload.`,
+		DefaultStatusCode: http.StatusNotFound,
+	},
+
+	{
+		Code:    ErrorCodeBlobUploadUnknown,
+		Value:   "BLOB_UPLOAD_UNKNOWN",
+		Message: "blob upload unknown to registry",
+		Description: `If a blob upload has been cancelled or was never
+		started, this error code may be returned.`,
+		DefaultStatusCode: http.StatusNotFound,
+	},
+}
+
+var errorCodeToDescriptors map[ErrorCode]ErrorDescriptor
+var idToDescriptors map[string]ErrorDescriptor
+
+func init() {
+	errorCodeToDescriptors = make(map[ErrorCode]ErrorDescriptor, len(descriptors))
+	idToDescriptors = make(map[string]ErrorDescriptor, len(descriptors))
+
+	for _, descriptor := range descriptors {
+		errorCodeToDescriptors[descriptor.Code] = descriptor
+		idToDescriptors[descriptor.Value] = descriptor
+	}
+}
diff --git a/api/errors/errors.go b/api/errors/errors.go
new file mode 100644
index 00000000..b6e64e2a
--- /dev/null
+++ b/api/errors/errors.go
@@ -0,0 +1,193 @@
+// Package errors describes the error codes that may be returned via the
+// Docker Registry JSON HTTP API V2. In addition to declaractions,
+// descriptions about the error codes and the conditions causing them are
+// avialable in detail.
+//
+// Error definitions here are considered to be locked down for the V2 registry
+// api. Any changes must be considered carefully and should not proceed
+// without a change proposal in docker core.
+package errors
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ErrorCode represents the error type. The errors are serialized via strings
+// and the integer format may change and should *never* be exported.
+type ErrorCode int
+
+const (
+	// ErrorCodeUnknown is a catch-all for errors not defined below.
+	ErrorCodeUnknown ErrorCode = iota
+
+	// ErrorCodeDigestInvalid is returned when uploading a blob if the
+	// provided digest does not match the blob contents.
+	ErrorCodeDigestInvalid
+
+	// ErrorCodeSizeInvalid is returned when uploading a blob if the provided
+	// size does not match the content length.
+	ErrorCodeSizeInvalid
+
+	// ErrorCodeNameInvalid is returned when the name in the manifest does not
+	// match the provided name.
+	ErrorCodeNameInvalid
+
+	// ErrorCodeTagInvalid is returned when the tag in the manifest does not
+	// match the provided tag.
+	ErrorCodeTagInvalid
+
+	// ErrorCodeNameUnknown when the repository name is not known.
+	ErrorCodeNameUnknown
+
+	// ErrorCodeManifestUnknown returned when image manifest is unknown.
+	ErrorCodeManifestUnknown
+
+	// ErrorCodeManifestInvalid returned when an image manifest is invalid,
+	// typically during a PUT operation. This error encompasses all errors
+	// encountered during manifest validation that aren't signature errors.
+	ErrorCodeManifestInvalid
+
+	// ErrorCodeManifestUnverified is returned when the manifest fails
+	// signature verfication.
+	ErrorCodeManifestUnverified
+
+	// ErrorCodeBlobUnknown is returned when a blob is unknown to the
+	// registry. This can happen when the manifest references a nonexistent
+	// layer or the result is not found by a blob fetch.
+	ErrorCodeBlobUnknown
+
+	// ErrorCodeBlobUploadUnknown is returned when an upload is unknown.
+	ErrorCodeBlobUploadUnknown
+)
+
+// ParseErrorCode attempts to parse the error code string, returning
+// ErrorCodeUnknown if the error is not known.
+func ParseErrorCode(s string) ErrorCode {
+	desc, ok := idToDescriptors[s]
+
+	if !ok {
+		return ErrorCodeUnknown
+	}
+
+	return desc.Code
+}
+
+// Descriptor returns the descriptor for the error code.
+func (ec ErrorCode) Descriptor() ErrorDescriptor {
+	d, ok := errorCodeToDescriptors[ec]
+
+	if !ok {
+		return ErrorCodeUnknown.Descriptor()
+	}
+
+	return d
+}
+
+// String returns the canonical identifier for this error code.
+func (ec ErrorCode) String() string {
+	return ec.Descriptor().Value
+}
+
+// Message returned the human-readable error message for this error code.
+func (ec ErrorCode) Message() string {
+	return ec.Descriptor().Message
+}
+
+// MarshalText encodes the receiver into UTF-8-encoded text and returns the
+// result.
+func (ec ErrorCode) MarshalText() (text []byte, err error) {
+	return []byte(ec.String()), nil
+}
+
+// UnmarshalText decodes the form generated by MarshalText.
+func (ec *ErrorCode) UnmarshalText(text []byte) error {
+	desc, ok := idToDescriptors[string(text)]
+
+	if !ok {
+		desc = ErrorCodeUnknown.Descriptor()
+	}
+
+	*ec = desc.Code
+
+	return nil
+}
+
+// Error provides a wrapper around ErrorCode with extra Details provided.
+type Error struct {
+	Code    ErrorCode   `json:"code"`
+	Message string      `json:"message,omitempty"`
+	Detail  interface{} `json:"detail,omitempty"`
+}
+
+// Error returns a human readable representation of the error.
+func (e Error) Error() string {
+	return fmt.Sprintf("%s: %s",
+		strings.ToLower(strings.Replace(e.Code.String(), "_", " ", -1)),
+		e.Message)
+}
+
+// Errors provides the envelope for multiple errors and a few sugar methods
+// for use within the application.
+type Errors struct {
+	Errors []Error `json:"errors,omitempty"`
+}
+
+// Push pushes an error on to the error stack, with the optional detail
+// argument. It is a programming error (ie panic) to push more than one
+// detail at a time.
+func (errs *Errors) Push(code ErrorCode, details ...interface{}) {
+	if len(details) > 1 {
+		panic("please specify zero or one detail items for this error")
+	}
+
+	var detail interface{}
+	if len(details) > 0 {
+		detail = details[0]
+	}
+
+	if err, ok := detail.(error); ok {
+		detail = err.Error()
+	}
+
+	errs.PushErr(Error{
+		Code:    code,
+		Message: code.Message(),
+		Detail:  detail,
+	})
+}
+
+// PushErr pushes an error interface onto the error stack.
+func (errs *Errors) PushErr(err error) {
+	switch err.(type) {
+	case Error:
+		errs.Errors = append(errs.Errors, err.(Error))
+	default:
+		errs.Errors = append(errs.Errors, Error{Message: err.Error()})
+	}
+}
+
+func (errs *Errors) Error() string {
+	switch errs.Len() {
+	case 0:
+		return "<nil>"
+	case 1:
+		return errs.Errors[0].Error()
+	default:
+		msg := "errors:\n"
+		for _, err := range errs.Errors {
+			msg += err.Error() + "\n"
+		}
+		return msg
+	}
+}
+
+// Clear clears the errors.
+func (errs *Errors) Clear() {
+	errs.Errors = errs.Errors[:0]
+}
+
+// Len returns the current number of errors.
+func (errs *Errors) Len() int {
+	return len(errs.Errors)
+}
diff --git a/api/errors/errors_test.go b/api/errors/errors_test.go
new file mode 100644
index 00000000..f0712bef
--- /dev/null
+++ b/api/errors/errors_test.go
@@ -0,0 +1,165 @@
+package errors
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+
+	"github.com/docker/docker-registry/digest"
+)
+
+// TestErrorCodes ensures that error code format, mappings and
+// marshaling/unmarshaling. round trips are stable.
+func TestErrorCodes(t *testing.T) {
+	for _, desc := range descriptors {
+		if desc.Code.String() != desc.Value {
+			t.Fatalf("error code string incorrect: %q != %q", desc.Code.String(), desc.Value)
+		}
+
+		if desc.Code.Message() != desc.Message {
+			t.Fatalf("incorrect message for error code %v: %q != %q", desc.Code, desc.Code.Message(), desc.Message)
+		}
+
+		// Serialize the error code using the json library to ensure that we
+		// get a string and it works round trip.
+		p, err := json.Marshal(desc.Code)
+
+		if err != nil {
+			t.Fatalf("error marshaling error code %v: %v", desc.Code, err)
+		}
+
+		if len(p) <= 0 {
+			t.Fatalf("expected content in marshaled before for error code %v", desc.Code)
+		}
+
+		// First, unmarshal to interface and ensure we have a string.
+		var ecUnspecified interface{}
+		if err := json.Unmarshal(p, &ecUnspecified); err != nil {
+			t.Fatalf("error unmarshaling error code %v: %v", desc.Code, err)
+		}
+
+		if _, ok := ecUnspecified.(string); !ok {
+			t.Fatalf("expected a string for error code %v on unmarshal got a %T", desc.Code, ecUnspecified)
+		}
+
+		// Now, unmarshal with the error code type and ensure they are equal
+		var ecUnmarshaled ErrorCode
+		if err := json.Unmarshal(p, &ecUnmarshaled); err != nil {
+			t.Fatalf("error unmarshaling error code %v: %v", desc.Code, err)
+		}
+
+		if ecUnmarshaled != desc.Code {
+			t.Fatalf("unexpected error code during error code marshal/unmarshal: %v != %v", ecUnmarshaled, desc.Code)
+		}
+	}
+}
+
+// TestErrorsManagement does a quick check of the Errors type to ensure that
+// members are properly pushed and marshaled.
+func TestErrorsManagement(t *testing.T) {
+	var errs Errors
+
+	errs.Push(ErrorCodeDigestInvalid)
+	errs.Push(ErrorCodeBlobUnknown,
+		map[string]digest.Digest{"digest": "sometestblobsumdoesntmatter"})
+
+	p, err := json.Marshal(errs)
+
+	if err != nil {
+		t.Fatalf("error marashaling errors: %v", err)
+	}
+
+	expectedJSON := "{\"errors\":[{\"code\":\"DIGEST_INVALID\",\"message\":\"provided digest did not match uploaded content\"},{\"code\":\"BLOB_UNKNOWN\",\"message\":\"blob unknown to registry\",\"detail\":{\"digest\":\"sometestblobsumdoesntmatter\"}}]}"
+
+	if string(p) != expectedJSON {
+		t.Fatalf("unexpected json: %q != %q", string(p), expectedJSON)
+	}
+
+	errs.Clear()
+	errs.Push(ErrorCodeUnknown)
+	expectedJSON = "{\"errors\":[{\"code\":\"UNKNOWN\",\"message\":\"unknown error\"}]}"
+	p, err = json.Marshal(errs)
+
+	if err != nil {
+		t.Fatalf("error marashaling errors: %v", err)
+	}
+
+	if string(p) != expectedJSON {
+		t.Fatalf("unexpected json: %q != %q", string(p), expectedJSON)
+	}
+}
+
+// TestMarshalUnmarshal ensures that api errors can round trip through json
+// without losing information.
+func TestMarshalUnmarshal(t *testing.T) {
+
+	var errors Errors
+
+	for _, testcase := range []struct {
+		description string
+		err         Error
+	}{
+		{
+			description: "unknown error",
+			err: Error{
+
+				Code:    ErrorCodeUnknown,
+				Message: ErrorCodeUnknown.Descriptor().Message,
+			},
+		},
+		{
+			description: "unknown manifest",
+			err: Error{
+				Code:    ErrorCodeManifestUnknown,
+				Message: ErrorCodeManifestUnknown.Descriptor().Message,
+			},
+		},
+		{
+			description: "unknown manifest",
+			err: Error{
+				Code:    ErrorCodeBlobUnknown,
+				Message: ErrorCodeBlobUnknown.Descriptor().Message,
+				Detail:  map[string]interface{}{"digest": "asdfqwerqwerqwerqwer"},
+			},
+		},
+	} {
+		fatalf := func(format string, args ...interface{}) {
+			t.Fatalf(testcase.description+": "+format, args...)
+		}
+
+		unexpectedErr := func(err error) {
+			fatalf("unexpected error: %v", err)
+		}
+
+		p, err := json.Marshal(testcase.err)
+		if err != nil {
+			unexpectedErr(err)
+		}
+
+		var unmarshaled Error
+		if err := json.Unmarshal(p, &unmarshaled); err != nil {
+			unexpectedErr(err)
+		}
+
+		if !reflect.DeepEqual(unmarshaled, testcase.err) {
+			fatalf("errors not equal after round trip: %#v != %#v", unmarshaled, testcase.err)
+		}
+
+		// Roll everything up into an error response envelope.
+		errors.PushErr(testcase.err)
+	}
+
+	p, err := json.Marshal(errors)
+	if err != nil {
+		t.Fatalf("unexpected error marshaling error envelope: %v", err)
+	}
+
+	var unmarshaled Errors
+	if err := json.Unmarshal(p, &unmarshaled); err != nil {
+		t.Fatalf("unexpected error unmarshaling error envelope: %v", err)
+	}
+
+	if !reflect.DeepEqual(unmarshaled, errors) {
+		t.Fatalf("errors not equal after round trip: %#v != %#v", unmarshaled, errors)
+	}
+}
diff --git a/api_test.go b/api_test.go
index 15ba0ca6..2c832a17 100644
--- a/api_test.go
+++ b/api_test.go
@@ -12,16 +12,14 @@ import (
 	"os"
 	"testing"
 
-	"github.com/docker/libtrust"
-
-	"github.com/docker/docker-registry/storage"
-	_ "github.com/docker/docker-registry/storagedriver/inmemory"
-
-	"github.com/gorilla/handlers"
-
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/common/testutil"
 	"github.com/docker/docker-registry/configuration"
 	"github.com/docker/docker-registry/digest"
+	"github.com/docker/docker-registry/storage"
+	_ "github.com/docker/docker-registry/storagedriver/inmemory"
+	"github.com/docker/libtrust"
+	"github.com/gorilla/handlers"
 )
 
 // TestLayerAPI conducts a full of the of the layer api.
@@ -133,6 +131,10 @@ func TestLayerAPI(t *testing.T) {
 	if !verifier.Verified() {
 		t.Fatalf("response body did not pass verification")
 	}
+
+	// Missing tests:
+	// 	- Upload the same tarsum file under and different repository and
+	//       ensure the content remains uncorrupted.
 }
 
 func TestManifestAPI(t *testing.T) {
@@ -180,9 +182,7 @@ func TestManifestAPI(t *testing.T) {
 	// }
 	dec := json.NewDecoder(resp.Body)
 
-	var respErrs struct {
-		Errors []Error
-	}
+	var respErrs errors.Errors
 	if err := dec.Decode(&respErrs); err != nil {
 		t.Fatalf("unexpected error decoding error response: %v", err)
 	}
@@ -191,7 +191,7 @@ func TestManifestAPI(t *testing.T) {
 		t.Fatalf("expected errors in response")
 	}
 
-	if respErrs.Errors[0].Code != ErrorCodeUnknownManifest {
+	if respErrs.Errors[0].Code != errors.ErrorCodeManifestUnknown {
 		t.Fatalf("expected manifest unknown error: got %v", respErrs)
 	}
 
@@ -217,7 +217,7 @@ func TestManifestAPI(t *testing.T) {
 		t.Fatalf("expected errors in response")
 	}
 
-	if respErrs.Errors[0].Code != ErrorCodeUnknownRepository {
+	if respErrs.Errors[0].Code != errors.ErrorCodeNameUnknown {
 		t.Fatalf("expected respository unknown error: got %v", respErrs)
 	}
 
@@ -251,11 +251,11 @@ func TestManifestAPI(t *testing.T) {
 
 	for _, err := range respErrs.Errors {
 		switch err.Code {
-		case ErrorCodeUnverifiedManifest:
+		case errors.ErrorCodeManifestUnverified:
 			unverified++
-		case ErrorCodeUnknownLayer:
+		case errors.ErrorCodeBlobUnknown:
 			missingLayers++
-		case ErrorCodeInvalidDigest:
+		case errors.ErrorCodeDigestInvalid:
 			// TODO(stevvooe): This error isn't quite descriptive enough --
 			// the layer with an invalid digest isn't identified.
 			invalidDigests++
diff --git a/client/client.go b/client/client.go
index e51476cd..0d343209 100644
--- a/client/client.go
+++ b/client/client.go
@@ -10,7 +10,7 @@ import (
 	"regexp"
 	"strconv"
 
-	"github.com/docker/docker-registry"
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/digest"
 	"github.com/docker/docker-registry/storage"
 )
@@ -94,17 +94,18 @@ func (r *clientImpl) GetImageManifest(name, tag string) (*storage.SignedManifest
 	case response.StatusCode == http.StatusOK:
 		break
 	case response.StatusCode == http.StatusNotFound:
-		return nil, &registry.ImageManifestNotFoundError{Name: name, Tag: tag}
+		return nil, &ImageManifestNotFoundError{Name: name, Tag: tag}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
+
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return nil, err
 		}
-		return nil, errors
+		return nil, &errs
 	default:
-		return nil, &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return nil, &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 
 	decoder := json.NewDecoder(response.Body)
@@ -118,13 +119,8 @@ func (r *clientImpl) GetImageManifest(name, tag string) (*storage.SignedManifest
 }
 
 func (r *clientImpl) PutImageManifest(name, tag string, manifest *storage.SignedManifest) error {
-	manifestBytes, err := json.Marshal(manifest)
-	if err != nil {
-		return err
-	}
-
 	putRequest, err := http.NewRequest("PUT",
-		r.imageManifestURL(name, tag), bytes.NewReader(manifestBytes))
+		r.imageManifestURL(name, tag), bytes.NewReader(manifest.Raw))
 	if err != nil {
 		return err
 	}
@@ -140,15 +136,16 @@ func (r *clientImpl) PutImageManifest(name, tag string, manifest *storage.Signed
 	case response.StatusCode == http.StatusOK:
 		return nil
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errors errors.Errors
 		decoder := json.NewDecoder(response.Body)
 		err = decoder.Decode(&errors)
 		if err != nil {
 			return err
 		}
-		return errors
+
+		return &errors
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -170,17 +167,17 @@ func (r *clientImpl) DeleteImage(name, tag string) error {
 	case response.StatusCode == http.StatusNoContent:
 		break
 	case response.StatusCode == http.StatusNotFound:
-		return &registry.ImageManifestNotFoundError{Name: name, Tag: tag}
+		return &ImageManifestNotFoundError{Name: name, Tag: tag}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return err
 		}
-		return errors
+		return &errs
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 
 	return nil
@@ -198,17 +195,17 @@ func (r *clientImpl) ListImageTags(name string) ([]string, error) {
 	case response.StatusCode == http.StatusOK:
 		break
 	case response.StatusCode == http.StatusNotFound:
-		return nil, &registry.RepositoryNotFoundError{Name: name}
+		return nil, &RepositoryNotFoundError{Name: name}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return nil, err
 		}
-		return nil, errors
+		return nil, &errs
 	default:
-		return nil, &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return nil, &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 
 	tags := struct {
@@ -235,7 +232,7 @@ func (r *clientImpl) BlobLength(name string, dgst digest.Digest) (int, error) {
 	switch {
 	case response.StatusCode == http.StatusOK:
 		lengthHeader := response.Header.Get("Content-Length")
-		length, err := strconv.ParseInt(lengthHeader, 10, 0)
+		length, err := strconv.ParseInt(lengthHeader, 10, 64)
 		if err != nil {
 			return -1, err
 		}
@@ -243,16 +240,16 @@ func (r *clientImpl) BlobLength(name string, dgst digest.Digest) (int, error) {
 	case response.StatusCode == http.StatusNotFound:
 		return -1, nil
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return -1, err
 		}
-		return -1, errors
+		return -1, &errs
 	default:
 		response.Body.Close()
-		return -1, &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return -1, &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -280,18 +277,18 @@ func (r *clientImpl) GetBlob(name string, dgst digest.Digest, byteOffset int) (i
 		return response.Body, int(length), nil
 	case response.StatusCode == http.StatusNotFound:
 		response.Body.Close()
-		return nil, 0, &registry.BlobNotFoundError{Name: name, Digest: dgst}
+		return nil, 0, &BlobNotFoundError{Name: name, Digest: dgst}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return nil, 0, err
 		}
-		return nil, 0, errors
+		return nil, 0, &errs
 	default:
 		response.Body.Close()
-		return nil, 0, &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return nil, 0, &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -315,20 +312,20 @@ func (r *clientImpl) InitiateBlobUpload(name string) (string, error) {
 	// case response.StatusCode == http.StatusNotFound:
 	// return
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return "", err
 		}
-		return "", errors
+		return "", &errs
 	default:
-		return "", &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return "", &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
 func (r *clientImpl) GetBlobUploadStatus(location string) (int, int, error) {
-	response, err := http.Get(fmt.Sprintf("%s%s", r.Endpoint, location))
+	response, err := http.Get(location)
 	if err != nil {
 		return 0, 0, err
 	}
@@ -339,31 +336,30 @@ func (r *clientImpl) GetBlobUploadStatus(location string) (int, int, error) {
 	case response.StatusCode == http.StatusNoContent:
 		return parseRangeHeader(response.Header.Get("Range"))
 	case response.StatusCode == http.StatusNotFound:
-		return 0, 0, &registry.BlobUploadNotFoundError{Location: location}
+		return 0, 0, &BlobUploadNotFoundError{Location: location}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return 0, 0, err
 		}
-		return 0, 0, errors
+		return 0, 0, &errs
 	default:
-		return 0, 0, &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return 0, 0, &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
 func (r *clientImpl) UploadBlob(location string, blob io.ReadCloser, length int, dgst digest.Digest) error {
 	defer blob.Close()
 
-	putRequest, err := http.NewRequest("PUT",
-		fmt.Sprintf("%s%s", r.Endpoint, location), blob)
+	putRequest, err := http.NewRequest("PUT", location, blob)
 	if err != nil {
 		return err
 	}
 
 	queryValues := url.Values{}
-	queryValues.Set("length", fmt.Sprint(length))
+	queryValues.Set("size", fmt.Sprint(length))
 	queryValues.Set("digest", dgst.String())
 	putRequest.URL.RawQuery = queryValues.Encode()
 
@@ -381,17 +377,17 @@ func (r *clientImpl) UploadBlob(location string, blob io.ReadCloser, length int,
 	case response.StatusCode == http.StatusCreated:
 		return nil
 	case response.StatusCode == http.StatusNotFound:
-		return &registry.BlobUploadNotFoundError{Location: location}
+		return &BlobUploadNotFoundError{Location: location}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return err
 		}
-		return errors
+		return &errs
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -426,23 +422,23 @@ func (r *clientImpl) UploadBlobChunk(location string, blobChunk io.ReadCloser, l
 		if err != nil {
 			return err
 		}
-		return &registry.BlobUploadInvalidRangeError{
+		return &BlobUploadInvalidRangeError{
 			Location:       location,
 			LastValidRange: lastValidRange,
 			BlobSize:       blobSize,
 		}
 	case response.StatusCode == http.StatusNotFound:
-		return &registry.BlobUploadNotFoundError{Location: location}
+		return &BlobUploadNotFoundError{Location: location}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return err
 		}
-		return errors
+		return &errs
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -454,7 +450,7 @@ func (r *clientImpl) FinishChunkedBlobUpload(location string, length int, dgst d
 	}
 
 	queryValues := new(url.Values)
-	queryValues.Set("length", fmt.Sprint(length))
+	queryValues.Set("size", fmt.Sprint(length))
 	queryValues.Set("digest", dgst.String())
 	putRequest.URL.RawQuery = queryValues.Encode()
 
@@ -474,17 +470,17 @@ func (r *clientImpl) FinishChunkedBlobUpload(location string, length int, dgst d
 	case response.StatusCode == http.StatusCreated:
 		return nil
 	case response.StatusCode == http.StatusNotFound:
-		return &registry.BlobUploadNotFoundError{Location: location}
+		return &BlobUploadNotFoundError{Location: location}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return err
 		}
-		return errors
+		return &errs
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
@@ -506,17 +502,17 @@ func (r *clientImpl) CancelBlobUpload(location string) error {
 	case response.StatusCode == http.StatusNoContent:
 		return nil
 	case response.StatusCode == http.StatusNotFound:
-		return &registry.BlobUploadNotFoundError{Location: location}
+		return &BlobUploadNotFoundError{Location: location}
 	case response.StatusCode >= 400 && response.StatusCode < 500:
-		errors := new(registry.Errors)
+		var errs errors.Errors
 		decoder := json.NewDecoder(response.Body)
-		err = decoder.Decode(&errors)
+		err = decoder.Decode(&errs)
 		if err != nil {
 			return err
 		}
-		return errors
+		return &errs
 	default:
-		return &registry.UnexpectedHTTPStatusError{Status: response.Status}
+		return &UnexpectedHTTPStatusError{Status: response.Status}
 	}
 }
 
diff --git a/client/client_test.go b/client/client_test.go
index 5eaf6b97..979f1313 100644
--- a/client/client_test.go
+++ b/client/client_test.go
@@ -58,7 +58,8 @@ func TestPush(t *testing.T) {
 			},
 		},
 	}
-	manifestBytes, err := json.Marshal(manifest)
+	var err error
+	manifest.Raw, err = json.Marshal(manifest)
 
 	blobRequestResponseMappings := make([]testutil.RequestResponseMapping, 2*len(testBlobs))
 	for i, blob := range testBlobs {
@@ -94,13 +95,25 @@ func TestPush(t *testing.T) {
 		Request: testutil.Request{
 			Method: "PUT",
 			Route:  "/v2/" + name + "/manifest/" + tag,
-			Body:   manifestBytes,
+			Body:   manifest.Raw,
 		},
 		Response: testutil.Response{
 			StatusCode: http.StatusOK,
 		},
 	}))
-	server := httptest.NewServer(handler)
+	var server *httptest.Server
+
+	// HACK(stevvooe): Super hack to follow: the request response map approach
+	// above does not let us correctly format the location header to the
+	// server url. This handler intercepts and re-writes the location header
+	// to the server url.
+
+	hack := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w = &headerInterceptingResponseWriter{ResponseWriter: w, serverURL: server.URL}
+		handler.ServeHTTP(w, r)
+	})
+
+	server = httptest.NewServer(hack)
 	client := New(server.URL)
 	objectStore := &memoryObjectStore{
 		mutex:           new(sync.Mutex),
@@ -370,3 +383,19 @@ func TestPullResume(t *testing.T) {
 		}
 	}
 }
+
+// headerInterceptingResponseWriter is a hacky workaround to re-write the
+// location header to have the server url.
+type headerInterceptingResponseWriter struct {
+	http.ResponseWriter
+	serverURL string
+}
+
+func (hirw *headerInterceptingResponseWriter) WriteHeader(status int) {
+	location := hirw.Header().Get("Location")
+	if location != "" {
+		hirw.Header().Set("Location", hirw.serverURL+location)
+	}
+
+	hirw.ResponseWriter.WriteHeader(status)
+}
diff --git a/client/errors.go b/client/errors.go
new file mode 100644
index 00000000..9bb2e40f
--- /dev/null
+++ b/client/errors.go
@@ -0,0 +1,79 @@
+package client
+
+import (
+	"fmt"
+
+	"github.com/docker/docker-registry/digest"
+)
+
+// RepositoryNotFoundError is returned when making an operation against a
+// repository that does not exist in the registry.
+type RepositoryNotFoundError struct {
+	Name string
+}
+
+func (e *RepositoryNotFoundError) Error() string {
+	return fmt.Sprintf("No repository found with Name: %s", e.Name)
+}
+
+// ImageManifestNotFoundError is returned when making an operation against a
+// given image manifest that does not exist in the registry.
+type ImageManifestNotFoundError struct {
+	Name string
+	Tag  string
+}
+
+func (e *ImageManifestNotFoundError) Error() string {
+	return fmt.Sprintf("No manifest found with Name: %s, Tag: %s",
+		e.Name, e.Tag)
+}
+
+// BlobNotFoundError is returned when making an operation against a given image
+// layer that does not exist in the registry.
+type BlobNotFoundError struct {
+	Name   string
+	Digest digest.Digest
+}
+
+func (e *BlobNotFoundError) Error() string {
+	return fmt.Sprintf("No blob found with Name: %s, Digest: %s",
+		e.Name, e.Digest)
+}
+
+// BlobUploadNotFoundError is returned when making a blob upload operation against an
+// invalid blob upload location url.
+// This may be the result of using a cancelled, completed, or stale upload
+// location.
+type BlobUploadNotFoundError struct {
+	Location string
+}
+
+func (e *BlobUploadNotFoundError) Error() string {
+	return fmt.Sprintf("No blob upload found at Location: %s", e.Location)
+}
+
+// BlobUploadInvalidRangeError is returned when attempting to upload an image
+// blob chunk that is out of order.
+// This provides the known BlobSize and LastValidRange which can be used to
+// resume the upload.
+type BlobUploadInvalidRangeError struct {
+	Location       string
+	LastValidRange int
+	BlobSize       int
+}
+
+func (e *BlobUploadInvalidRangeError) Error() string {
+	return fmt.Sprintf(
+		"Invalid range provided for upload at Location: %s. Last Valid Range: %d, Blob Size: %d",
+		e.Location, e.LastValidRange, e.BlobSize)
+}
+
+// UnexpectedHTTPStatusError is returned when an unexpected HTTP status is
+// returned when making a registry api call.
+type UnexpectedHTTPStatusError struct {
+	Status string
+}
+
+func (e *UnexpectedHTTPStatusError) Error() string {
+	return fmt.Sprintf("Received unexpected HTTP status: %s", e.Status)
+}
diff --git a/context.go b/context.go
index 8d894e0f..a1e47abe 100644
--- a/context.go
+++ b/context.go
@@ -1,6 +1,9 @@
 package registry
 
-import "github.com/Sirupsen/logrus"
+import (
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker-registry/api/errors"
+)
 
 // Context should contain the request specific context for use in across
 // handlers. Resources that don't need to be shared across handlers should not
@@ -16,7 +19,7 @@ type Context struct {
 	// Errors is a collection of errors encountered during the request to be
 	// returned to the client API. If errors are added to the collection, the
 	// handler *must not* start the response via http.ResponseWriter.
-	Errors Errors
+	Errors errors.Errors
 
 	// vars contains the extracted gorilla/mux variables that can be used for
 	// assignment.
diff --git a/errors.go b/errors.go
deleted file mode 100644
index 17758f44..00000000
--- a/errors.go
+++ /dev/null
@@ -1,311 +0,0 @@
-package registry
-
-import (
-	"fmt"
-	"strings"
-
-	"github.com/docker/docker-registry/digest"
-	"github.com/docker/docker-registry/storage"
-)
-
-// ErrorCode represents the error type. The errors are serialized via strings
-// and the integer format may change and should *never* be exported.
-type ErrorCode int
-
-const (
-	// ErrorCodeUnknown is a catch-all for errors not defined below.
-	ErrorCodeUnknown ErrorCode = iota
-
-	// The following errors can happen during a layer upload.
-
-	// ErrorCodeInvalidDigest is returned when uploading a layer if the
-	// provided digest does not match the layer contents.
-	ErrorCodeInvalidDigest
-
-	// ErrorCodeInvalidLength is returned when uploading a layer if the provided
-	// length does not match the content length.
-	ErrorCodeInvalidLength
-
-	// ErrorCodeInvalidName is returned when the name in the manifest does not
-	// match the provided name.
-	ErrorCodeInvalidName
-
-	// ErrorCodeInvalidTag is returned when the tag in the manifest does not
-	// match the provided tag.
-	ErrorCodeInvalidTag
-
-	// ErrorCodeUnknownRepository when the repository name is not known.
-	ErrorCodeUnknownRepository
-
-	// ErrorCodeUnknownManifest returned when image manifest name and tag is
-	// unknown, accompanied by a 404 status.
-	ErrorCodeUnknownManifest
-
-	// ErrorCodeInvalidManifest returned when an image manifest is invalid,
-	// typically during a PUT operation.
-	ErrorCodeInvalidManifest
-
-	// ErrorCodeUnverifiedManifest is returned when the manifest fails signature
-	// validation.
-	ErrorCodeUnverifiedManifest
-
-	// ErrorCodeUnknownLayer is returned when the manifest references a
-	// nonexistent layer.
-	ErrorCodeUnknownLayer
-
-	// ErrorCodeUnknownLayerUpload is returned when an upload is accessed.
-	ErrorCodeUnknownLayerUpload
-
-	// ErrorCodeUntrustedSignature is returned when the manifest is signed by an
-	// untrusted source.
-	ErrorCodeUntrustedSignature
-)
-
-var errorCodeStrings = map[ErrorCode]string{
-	ErrorCodeUnknown:            "UNKNOWN",
-	ErrorCodeInvalidDigest:      "INVALID_DIGEST",
-	ErrorCodeInvalidLength:      "INVALID_LENGTH",
-	ErrorCodeInvalidName:        "INVALID_NAME",
-	ErrorCodeInvalidTag:         "INVALID_TAG",
-	ErrorCodeUnknownRepository:  "UNKNOWN_REPOSITORY",
-	ErrorCodeUnknownManifest:    "UNKNOWN_MANIFEST",
-	ErrorCodeInvalidManifest:    "INVALID_MANIFEST",
-	ErrorCodeUnverifiedManifest: "UNVERIFIED_MANIFEST",
-	ErrorCodeUnknownLayer:       "UNKNOWN_LAYER",
-	ErrorCodeUnknownLayerUpload: "UNKNOWN_LAYER_UPLOAD",
-	ErrorCodeUntrustedSignature: "UNTRUSTED_SIGNATURE",
-}
-
-var errorCodesMessages = map[ErrorCode]string{
-	ErrorCodeUnknown:            "unknown error",
-	ErrorCodeInvalidDigest:      "provided digest did not match uploaded content",
-	ErrorCodeInvalidLength:      "provided length did not match content length",
-	ErrorCodeInvalidName:        "manifest name did not match URI",
-	ErrorCodeInvalidTag:         "manifest tag did not match URI",
-	ErrorCodeUnknownRepository:  "repository not known to registry",
-	ErrorCodeUnknownManifest:    "manifest not known",
-	ErrorCodeInvalidManifest:    "manifest is invalid",
-	ErrorCodeUnverifiedManifest: "manifest failed signature validation",
-	ErrorCodeUnknownLayer:       "referenced layer not available",
-	ErrorCodeUnknownLayerUpload: "cannot resume unknown layer upload",
-	ErrorCodeUntrustedSignature: "manifest signed by untrusted source",
-}
-
-var stringToErrorCode map[string]ErrorCode
-
-func init() {
-	stringToErrorCode = make(map[string]ErrorCode, len(errorCodeStrings))
-
-	// Build up reverse error code map
-	for k, v := range errorCodeStrings {
-		stringToErrorCode[v] = k
-	}
-}
-
-// ParseErrorCode attempts to parse the error code string, returning
-// ErrorCodeUnknown if the error is not known.
-func ParseErrorCode(s string) ErrorCode {
-	ec, ok := stringToErrorCode[s]
-
-	if !ok {
-		return ErrorCodeUnknown
-	}
-
-	return ec
-}
-
-// String returns the canonical identifier for this error code.
-func (ec ErrorCode) String() string {
-	s, ok := errorCodeStrings[ec]
-
-	if !ok {
-		return errorCodeStrings[ErrorCodeUnknown]
-	}
-
-	return s
-}
-
-// Message returned the human-readable error message for this error code.
-func (ec ErrorCode) Message() string {
-	m, ok := errorCodesMessages[ec]
-
-	if !ok {
-		return errorCodesMessages[ErrorCodeUnknown]
-	}
-
-	return m
-}
-
-// MarshalText encodes the receiver into UTF-8-encoded text and returns the
-// result.
-func (ec ErrorCode) MarshalText() (text []byte, err error) {
-	return []byte(ec.String()), nil
-}
-
-// UnmarshalText decodes the form generated by MarshalText.
-func (ec *ErrorCode) UnmarshalText(text []byte) error {
-	*ec = stringToErrorCode[string(text)]
-
-	return nil
-}
-
-// Error provides a wrapper around ErrorCode with extra Details provided.
-type Error struct {
-	Code    ErrorCode   `json:"code"`
-	Message string      `json:"message,omitempty"`
-	Detail  interface{} `json:"detail,omitempty"`
-}
-
-// Error returns a human readable representation of the error.
-func (e Error) Error() string {
-	return fmt.Sprintf("%s: %s",
-		strings.ToLower(strings.Replace(e.Code.String(), "_", " ", -1)),
-		e.Message)
-}
-
-// Errors provides the envelope for multiple errors and a few sugar methods
-// for use within the application.
-type Errors struct {
-	Errors []error `json:"errors,omitempty"`
-}
-
-// Push pushes an error on to the error stack, with the optional detail
-// argument. It is a programming error (ie panic) to push more than one
-// detail at a time.
-func (errs *Errors) Push(code ErrorCode, details ...interface{}) {
-	if len(details) > 1 {
-		panic("please specify zero or one detail items for this error")
-	}
-
-	var detail interface{}
-	if len(details) > 0 {
-		detail = details[0]
-	}
-
-	if err, ok := detail.(error); ok {
-		detail = err.Error()
-	}
-
-	errs.PushErr(Error{
-		Code:    code,
-		Message: code.Message(),
-		Detail:  detail,
-	})
-}
-
-// PushErr pushes an error interface onto the error stack.
-func (errs *Errors) PushErr(err error) {
-	switch err.(type) {
-	case Error:
-		errs.Errors = append(errs.Errors, err)
-	default:
-		errs.Errors = append(errs.Errors, Error{Message: err.Error()})
-	}
-}
-
-func (errs *Errors) Error() string {
-	switch errs.Len() {
-	case 0:
-		return "<nil>"
-	case 1:
-		return errs.Errors[0].Error()
-	default:
-		msg := "errors:\n"
-		for _, err := range errs.Errors {
-			msg += err.Error() + "\n"
-		}
-		return msg
-	}
-}
-
-// Clear clears the errors.
-func (errs *Errors) Clear() {
-	errs.Errors = errs.Errors[:0]
-}
-
-// Len returns the current number of errors.
-func (errs *Errors) Len() int {
-	return len(errs.Errors)
-}
-
-// DetailUnknownLayer provides detail for unknown layer errors, returned by
-// image manifest push for layers that are not yet transferred. This intended
-// to only be used on the backend to return detail for this specific error.
-type DetailUnknownLayer struct {
-
-	// Unknown should contain the contents of a layer descriptor, which is a
-	// single FSLayer currently.
-	Unknown storage.FSLayer `json:"unknown"`
-}
-
-// RepositoryNotFoundError is returned when making an operation against a
-// repository that does not exist in the registry.
-type RepositoryNotFoundError struct {
-	Name string
-}
-
-func (e *RepositoryNotFoundError) Error() string {
-	return fmt.Sprintf("No repository found with Name: %s", e.Name)
-}
-
-// ImageManifestNotFoundError is returned when making an operation against a
-// given image manifest that does not exist in the registry.
-type ImageManifestNotFoundError struct {
-	Name string
-	Tag  string
-}
-
-func (e *ImageManifestNotFoundError) Error() string {
-	return fmt.Sprintf("No manifest found with Name: %s, Tag: %s",
-		e.Name, e.Tag)
-}
-
-// BlobNotFoundError is returned when making an operation against a given image
-// layer that does not exist in the registry.
-type BlobNotFoundError struct {
-	Name   string
-	Digest digest.Digest
-}
-
-func (e *BlobNotFoundError) Error() string {
-	return fmt.Sprintf("No blob found with Name: %s, Digest: %s",
-		e.Name, e.Digest)
-}
-
-// BlobUploadNotFoundError is returned when making a blob upload operation against an
-// invalid blob upload location url.
-// This may be the result of using a cancelled, completed, or stale upload
-// location.
-type BlobUploadNotFoundError struct {
-	Location string
-}
-
-func (e *BlobUploadNotFoundError) Error() string {
-	return fmt.Sprintf("No blob upload found at Location: %s", e.Location)
-}
-
-// BlobUploadInvalidRangeError is returned when attempting to upload an image
-// blob chunk that is out of order.
-// This provides the known BlobSize and LastValidRange which can be used to
-// resume the upload.
-type BlobUploadInvalidRangeError struct {
-	Location       string
-	LastValidRange int
-	BlobSize       int
-}
-
-func (e *BlobUploadInvalidRangeError) Error() string {
-	return fmt.Sprintf(
-		"Invalid range provided for upload at Location: %s. Last Valid Range: %d, Blob Size: %d",
-		e.Location, e.LastValidRange, e.BlobSize)
-}
-
-// UnexpectedHTTPStatusError is returned when an unexpected HTTP status is
-// returned when making a registry api call.
-type UnexpectedHTTPStatusError struct {
-	Status string
-}
-
-func (e *UnexpectedHTTPStatusError) Error() string {
-	return fmt.Sprintf("Received unexpected HTTP status: %s", e.Status)
-}
diff --git a/errors_test.go b/errors_test.go
deleted file mode 100644
index e0392eb6..00000000
--- a/errors_test.go
+++ /dev/null
@@ -1,90 +0,0 @@
-package registry
-
-import (
-	"encoding/json"
-	"testing"
-)
-
-// TestErrorCodes ensures that error code format, mappings and
-// marshaling/unmarshaling. round trips are stable.
-func TestErrorCodes(t *testing.T) {
-	for ec := range errorCodeStrings {
-		if ec.String() != errorCodeStrings[ec] {
-			t.Fatalf("error code string incorrect: %q != %q", ec.String(), errorCodeStrings[ec])
-		}
-
-		if ec.Message() != errorCodesMessages[ec] {
-			t.Fatalf("incorrect message for error code %v: %q != %q", ec, ec.Message(), errorCodesMessages[ec])
-		}
-
-		// Serialize the error code using the json library to ensure that we
-		// get a string and it works round trip.
-		p, err := json.Marshal(ec)
-
-		if err != nil {
-			t.Fatalf("error marshaling error code %v: %v", ec, err)
-		}
-
-		if len(p) <= 0 {
-			t.Fatalf("expected content in marshaled before for error code %v", ec)
-		}
-
-		// First, unmarshal to interface and ensure we have a string.
-		var ecUnspecified interface{}
-		if err := json.Unmarshal(p, &ecUnspecified); err != nil {
-			t.Fatalf("error unmarshaling error code %v: %v", ec, err)
-		}
-
-		if _, ok := ecUnspecified.(string); !ok {
-			t.Fatalf("expected a string for error code %v on unmarshal got a %T", ec, ecUnspecified)
-		}
-
-		// Now, unmarshal with the error code type and ensure they are equal
-		var ecUnmarshaled ErrorCode
-		if err := json.Unmarshal(p, &ecUnmarshaled); err != nil {
-			t.Fatalf("error unmarshaling error code %v: %v", ec, err)
-		}
-
-		if ecUnmarshaled != ec {
-			t.Fatalf("unexpected error code during error code marshal/unmarshal: %v != %v", ecUnmarshaled, ec)
-		}
-	}
-}
-
-// TestErrorsManagement does a quick check of the Errors type to ensure that
-// members are properly pushed and marshaled.
-func TestErrorsManagement(t *testing.T) {
-	var errs Errors
-
-	errs.Push(ErrorCodeInvalidDigest)
-
-	var detail DetailUnknownLayer
-	detail.Unknown.BlobSum = "sometestblobsumdoesntmatter"
-
-	errs.Push(ErrorCodeUnknownLayer, detail)
-
-	p, err := json.Marshal(errs)
-
-	if err != nil {
-		t.Fatalf("error marashaling errors: %v", err)
-	}
-
-	expectedJSON := "{\"errors\":[{\"code\":\"INVALID_DIGEST\",\"message\":\"provided digest did not match uploaded content\"},{\"code\":\"UNKNOWN_LAYER\",\"message\":\"referenced layer not available\",\"detail\":{\"unknown\":{\"blobSum\":\"sometestblobsumdoesntmatter\"}}}]}"
-
-	if string(p) != expectedJSON {
-		t.Fatalf("unexpected json: %q != %q", string(p), expectedJSON)
-	}
-
-	errs.Clear()
-	errs.Push(ErrorCodeUnknown)
-	expectedJSON = "{\"errors\":[{\"code\":\"UNKNOWN\",\"message\":\"unknown error\"}]}"
-	p, err = json.Marshal(errs)
-
-	if err != nil {
-		t.Fatalf("error marashaling errors: %v", err)
-	}
-
-	if string(p) != expectedJSON {
-		t.Fatalf("unexpected json: %q != %q", string(p), expectedJSON)
-	}
-}
diff --git a/images.go b/images.go
index 495e193a..74ae067e 100644
--- a/images.go
+++ b/images.go
@@ -5,8 +5,8 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/digest"
-
 	"github.com/docker/docker-registry/storage"
 	"github.com/gorilla/handlers"
 )
@@ -41,7 +41,7 @@ func (imh *imageManifestHandler) GetImageManifest(w http.ResponseWriter, r *http
 	manifest, err := manifests.Get(imh.Name, imh.Tag)
 
 	if err != nil {
-		imh.Errors.Push(ErrorCodeUnknownManifest, err)
+		imh.Errors.Push(errors.ErrorCodeManifestUnknown, err)
 		w.WriteHeader(http.StatusNotFound)
 		return
 	}
@@ -58,7 +58,7 @@ func (imh *imageManifestHandler) PutImageManifest(w http.ResponseWriter, r *http
 
 	var manifest storage.SignedManifest
 	if err := dec.Decode(&manifest); err != nil {
-		imh.Errors.Push(ErrorCodeInvalidManifest, err)
+		imh.Errors.Push(errors.ErrorCodeManifestInvalid, err)
 		w.WriteHeader(http.StatusBadRequest)
 		return
 	}
@@ -71,14 +71,14 @@ func (imh *imageManifestHandler) PutImageManifest(w http.ResponseWriter, r *http
 			for _, verificationError := range err {
 				switch verificationError := verificationError.(type) {
 				case storage.ErrUnknownLayer:
-					imh.Errors.Push(ErrorCodeUnknownLayer, verificationError.FSLayer)
+					imh.Errors.Push(errors.ErrorCodeBlobUnknown, verificationError.FSLayer)
 				case storage.ErrManifestUnverified:
-					imh.Errors.Push(ErrorCodeUnverifiedManifest)
+					imh.Errors.Push(errors.ErrorCodeManifestUnverified)
 				default:
 					if verificationError == digest.ErrDigestInvalidFormat {
 						// TODO(stevvooe): We need to really need to move all
 						// errors to types. Its much more straightforward.
-						imh.Errors.Push(ErrorCodeInvalidDigest)
+						imh.Errors.Push(errors.ErrorCodeDigestInvalid)
 					} else {
 						imh.Errors.PushErr(verificationError)
 					}
@@ -99,10 +99,10 @@ func (imh *imageManifestHandler) DeleteImageManifest(w http.ResponseWriter, r *h
 	if err := manifests.Delete(imh.Name, imh.Tag); err != nil {
 		switch err := err.(type) {
 		case storage.ErrUnknownManifest:
-			imh.Errors.Push(ErrorCodeUnknownManifest, err)
+			imh.Errors.Push(errors.ErrorCodeManifestUnknown, err)
 			w.WriteHeader(http.StatusNotFound)
 		default:
-			imh.Errors.Push(ErrorCodeUnknown, err)
+			imh.Errors.Push(errors.ErrorCodeUnknown, err)
 			w.WriteHeader(http.StatusBadRequest)
 		}
 		return
diff --git a/layer.go b/layer.go
index 4d937c64..4da7723a 100644
--- a/layer.go
+++ b/layer.go
@@ -3,6 +3,7 @@ package registry
 import (
 	"net/http"
 
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/digest"
 	"github.com/docker/docker-registry/storage"
 	"github.com/gorilla/handlers"
@@ -14,7 +15,7 @@ func layerDispatcher(ctx *Context, r *http.Request) http.Handler {
 
 	if err != nil {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			ctx.Errors.Push(ErrorCodeInvalidDigest, err)
+			ctx.Errors.Push(errors.ErrorCodeDigestInvalid, err)
 		})
 	}
 
@@ -49,9 +50,9 @@ func (lh *layerHandler) GetLayer(w http.ResponseWriter, r *http.Request) {
 		switch err := err.(type) {
 		case storage.ErrUnknownLayer:
 			w.WriteHeader(http.StatusNotFound)
-			lh.Errors.Push(ErrorCodeUnknownLayer, err.FSLayer)
+			lh.Errors.Push(errors.ErrorCodeBlobUnknown, err.FSLayer)
 		default:
-			lh.Errors.Push(ErrorCodeUnknown, err)
+			lh.Errors.Push(errors.ErrorCodeUnknown, err)
 		}
 		return
 	}
diff --git a/layerupload.go b/layerupload.go
index d7aaa24f..af8bd457 100644
--- a/layerupload.go
+++ b/layerupload.go
@@ -7,6 +7,7 @@ import (
 	"strconv"
 
 	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/digest"
 	"github.com/docker/docker-registry/storage"
 	"github.com/gorilla/handlers"
@@ -38,7 +39,7 @@ func layerUploadDispatcher(ctx *Context, r *http.Request) http.Handler {
 			return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 				logrus.Infof("error resolving upload: %v", err)
 				w.WriteHeader(http.StatusInternalServerError)
-				luh.Errors.Push(ErrorCodeUnknown, err)
+				luh.Errors.Push(errors.ErrorCodeUnknown, err)
 			})
 		}
 
@@ -66,7 +67,7 @@ func (luh *layerUploadHandler) StartLayerUpload(w http.ResponseWriter, r *http.R
 	upload, err := layers.Upload(luh.Name)
 	if err != nil {
 		w.WriteHeader(http.StatusInternalServerError) // Error conditions here?
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		return
 	}
 
@@ -75,7 +76,7 @@ func (luh *layerUploadHandler) StartLayerUpload(w http.ResponseWriter, r *http.R
 
 	if err := luh.layerUploadResponse(w, r); err != nil {
 		w.WriteHeader(http.StatusInternalServerError) // Error conditions here?
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		return
 	}
 	w.WriteHeader(http.StatusAccepted)
@@ -85,12 +86,12 @@ func (luh *layerUploadHandler) StartLayerUpload(w http.ResponseWriter, r *http.R
 func (luh *layerUploadHandler) GetUploadStatus(w http.ResponseWriter, r *http.Request) {
 	if luh.Upload == nil {
 		w.WriteHeader(http.StatusNotFound)
-		luh.Errors.Push(ErrorCodeUnknownLayerUpload)
+		luh.Errors.Push(errors.ErrorCodeBlobUploadUnknown)
 	}
 
 	if err := luh.layerUploadResponse(w, r); err != nil {
 		w.WriteHeader(http.StatusInternalServerError) // Error conditions here?
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		return
 	}
 
@@ -102,7 +103,7 @@ func (luh *layerUploadHandler) GetUploadStatus(w http.ResponseWriter, r *http.Re
 func (luh *layerUploadHandler) PutLayerChunk(w http.ResponseWriter, r *http.Request) {
 	if luh.Upload == nil {
 		w.WriteHeader(http.StatusNotFound)
-		luh.Errors.Push(ErrorCodeUnknownLayerUpload)
+		luh.Errors.Push(errors.ErrorCodeBlobUploadUnknown)
 	}
 
 	var finished bool
@@ -119,14 +120,14 @@ func (luh *layerUploadHandler) PutLayerChunk(w http.ResponseWriter, r *http.Requ
 	if err := luh.maybeCompleteUpload(w, r); err != nil {
 		if err != errNotReadyToComplete {
 			w.WriteHeader(http.StatusInternalServerError)
-			luh.Errors.Push(ErrorCodeUnknown, err)
+			luh.Errors.Push(errors.ErrorCodeUnknown, err)
 			return
 		}
 	}
 
 	if err := luh.layerUploadResponse(w, r); err != nil {
 		w.WriteHeader(http.StatusInternalServerError) // Error conditions here?
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		return
 	}
 
@@ -141,7 +142,7 @@ func (luh *layerUploadHandler) PutLayerChunk(w http.ResponseWriter, r *http.Requ
 func (luh *layerUploadHandler) CancelLayerUpload(w http.ResponseWriter, r *http.Request) {
 	if luh.Upload == nil {
 		w.WriteHeader(http.StatusNotFound)
-		luh.Errors.Push(ErrorCodeUnknownLayerUpload)
+		luh.Errors.Push(errors.ErrorCodeBlobUploadUnknown)
 	}
 
 }
@@ -194,14 +195,14 @@ func (luh *layerUploadHandler) maybeCompleteUpload(w http.ResponseWriter, r *htt
 func (luh *layerUploadHandler) completeUpload(w http.ResponseWriter, r *http.Request, size int64, dgst digest.Digest) {
 	layer, err := luh.Upload.Finish(size, dgst)
 	if err != nil {
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		w.WriteHeader(http.StatusInternalServerError)
 		return
 	}
 
 	layerURL, err := luh.urlBuilder.forLayer(layer)
 	if err != nil {
-		luh.Errors.Push(ErrorCodeUnknown, err)
+		luh.Errors.Push(errors.ErrorCodeUnknown, err)
 		w.WriteHeader(http.StatusInternalServerError)
 		return
 	}
diff --git a/tags.go b/tags.go
index 4916c151..12a5062f 100644
--- a/tags.go
+++ b/tags.go
@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"net/http"
 
+	"github.com/docker/docker-registry/api/errors"
 	"github.com/docker/docker-registry/storage"
 	"github.com/gorilla/handlers"
 )
@@ -39,7 +40,7 @@ func (th *tagsHandler) GetTags(w http.ResponseWriter, r *http.Request) {
 		switch err := err.(type) {
 		case storage.ErrUnknownRepository:
 			w.WriteHeader(404)
-			th.Errors.Push(ErrorCodeUnknownRepository, map[string]string{"name": th.Name})
+			th.Errors.Push(errors.ErrorCodeNameUnknown, map[string]string{"name": th.Name})
 		default:
 			th.Errors.PushErr(err)
 		}