diff --git a/x509/openssl/repository.go b/x509/openssl/repository.go
index b06b418..85a1273 100644
--- a/x509/openssl/repository.go
+++ b/x509/openssl/repository.go
@@ -13,58 +13,10 @@ import (
 	"strings"
 	"sync"
 	"time"
-)
-
-var OidCRLReason = asn1.ObjectIdentifier{2, 5, 29, 21}
 
-type CRLReason int
-
-// CRL reason codes as defined in RFC 5280 section 5.3.1
-const (
-	CRLReasonUnspecified          CRLReason = 0
-	CRLReasonKeyCompromise        CRLReason = 1
-	CRLReasonCACompromise         CRLReason = 2
-	CRLReasonAffiliationChanged   CRLReason = 3
-	CRLReasonSuperseded           CRLReason = 4
-	CRLReasonCessationOfOperation CRLReason = 5
-	CRLReasonCertificateHold      CRLReason = 6
-	CRLReasonRemoveFromCRL        CRLReason = 8
-	CRLReasonPrivilegeWithdrawn   CRLReason = 9
-	CRLReasonAACompromise         CRLReason = 10
+	"git.cacert.org/cacert-gosigner/x509/revoking"
 )
 
-var crlReasonNames = map[CRLReason]string{
-	CRLReasonUnspecified:          "unspecified",
-	CRLReasonKeyCompromise:        "keyCompromise",
-	CRLReasonCACompromise:         "CACompromise",
-	CRLReasonAffiliationChanged:   "affiliationChanged",
-	CRLReasonSuperseded:           "superseded",
-	CRLReasonCessationOfOperation: "cessationOfOperation",
-	CRLReasonCertificateHold:      "certificateHold",
-	CRLReasonRemoveFromCRL:        "removeFromCRL",
-	CRLReasonPrivilegeWithdrawn:   "privilegeWithdrawn",
-	CRLReasonAACompromise:         "AACompromise",
-}
-
-func (r CRLReason) String() string {
-	if reason, ok := crlReasonNames[r]; ok {
-		return reason
-	}
-
-	return crlReasonNames[CRLReasonUnspecified]
-}
-
-// ParseReason takes a reason string and performs a case-insensitive match to a reason code
-func ParseReason(rs string) CRLReason {
-	for key, name := range crlReasonNames {
-		if strings.EqualFold(name, rs) {
-			return key
-		}
-	}
-
-	return CRLReasonUnspecified
-}
-
 const TimeSpec = "060102030405Z"
 
 type indexStatus string
@@ -81,7 +33,7 @@ type indexEntry struct {
 	statusFlag           indexStatus
 	expiresAt            time.Time
 	revokedAt            *time.Time
-	revocationReason     CRLReason
+	revocationReason     revoking.CRLReason
 	serialNumber         *big.Int
 	fileName             string
 	certificateSubjectDN string
@@ -119,7 +71,7 @@ type Repository struct {
 	entries       []indexEntry
 }
 
-func (ie *indexEntry) markRevoked(revocationTime time.Time, reason CRLReason) {
+func (ie *indexEntry) markRevoked(revocationTime time.Time, reason revoking.CRLReason) {
 	if ie.statusFlag == certificateValid {
 		ie.statusFlag = certificateRevoked
 		ie.revokedAt = &revocationTime
@@ -168,10 +120,10 @@ func (r *Repository) StoreRevocation(revoked *pkix.RevokedCertificate) error {
 		return CannotRevokeUnknown{Serial: revoked.SerialNumber}
 	}
 
-	reason := CRLReasonUnspecified
+	reason := revoking.CRLReasonUnspecified
 
 	for _, ext := range revoked.Extensions {
-		if ext.Id.Equal(OidCRLReason) {
+		if ext.Id.Equal(revoking.OidCRLReason) {
 			_, err := asn1.Unmarshal(ext.Value, &reason)
 			if err != nil {
 				return fmt.Errorf("could not unmarshal ")
@@ -225,6 +177,31 @@ func (r *Repository) StoreCertificate(signed *x509.Certificate) error {
 	return nil
 }
 
+func (r *Repository) RevokedCertificates() ([]pkix.RevokedCertificate, error) {
+	var err error
+
+	r.lock.Lock()
+	defer r.lock.Unlock()
+
+	err = r.loadIndex()
+	if err != nil {
+		return nil, err
+	}
+
+	result := make([]pkix.RevokedCertificate, 0)
+	for _, entry := range r.entries {
+		if entry.revokedAt != nil {
+			result = append(result, pkix.RevokedCertificate{
+				SerialNumber:   entry.serialNumber,
+				RevocationTime: *entry.revokedAt,
+				Extensions:     []pkix.Extension{entry.revocationReason.BuildExtension()},
+			})
+		}
+	}
+
+	return result, nil
+}
+
 func (r *Repository) loadIndex() error {
 	entries := make([]indexEntry, 0, 100)
 
@@ -320,14 +297,14 @@ func (r *Repository) newIndexEntryFromLine(text string) (*indexEntry, error) {
 	}
 
 	var revocationTimeParsed time.Time
-	var revocationReason CRLReason
+	var revocationReason revoking.CRLReason
 
 	if fields[2] != "" {
 		var timeString string
 		if strings.Contains(fields[2], ",") {
 			parts := strings.SplitN(fields[2], ",", 2)
 			timeString = parts[0]
-			revocationReason = ParseReason(parts[1])
+			revocationReason = revoking.ParseReason(parts[1])
 		} else {
 			timeString = fields[2]
 		}
diff --git a/x509/openssl/repository_test.go b/x509/openssl/repository_test.go
index 48fa186..c8269e4 100644
--- a/x509/openssl/repository_test.go
+++ b/x509/openssl/repository_test.go
@@ -4,7 +4,6 @@ import (
 	"crypto/rand"
 	"crypto/x509"
 	"crypto/x509/pkix"
-	"encoding/asn1"
 	"math/big"
 	"os"
 	"path"
@@ -13,6 +12,7 @@ import (
 	"time"
 
 	"git.cacert.org/cacert-gosigner/x509/openssl"
+	"git.cacert.org/cacert-gosigner/x509/revoking"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -28,19 +28,12 @@ func TestStoreRevocation(t *testing.T) {
 		t.Errorf("could not create random serial: %v", err)
 	}
 
-	extBytes, err := asn1.Marshal(openssl.CRLReasonKeyCompromise)
-	if err != nil {
-		t.Errorf("could not marshal revocation reason: %v", err)
-	}
-
 	notAfter := time.Now().UTC().Add(24 * time.Hour).UTC()
 
 	err = fr.StoreRevocation(&pkix.RevokedCertificate{
 		SerialNumber:   serial,
 		RevocationTime: notAfter,
-		Extensions: []pkix.Extension{
-			{Id: openssl.OidCRLReason, Value: extBytes},
-		},
+		Extensions:     []pkix.Extension{revoking.CRLReasonKeyCompromise.BuildExtension()},
 	})
 
 	assert.ErrorIs(t, err, openssl.CannotRevokeUnknown{Serial: serial})
@@ -63,9 +56,7 @@ func TestStoreRevocation(t *testing.T) {
 	err = fr.StoreRevocation(&pkix.RevokedCertificate{
 		SerialNumber:   serial,
 		RevocationTime: time.Now(),
-		Extensions: []pkix.Extension{
-			{Id: openssl.OidCRLReason, Value: extBytes},
-		},
+		Extensions:     []pkix.Extension{revoking.CRLReasonKeyCompromise.BuildExtension()},
 	})
 	assert.NoError(t, err)
 
diff --git a/x509/revoking/repository.go b/x509/revoking/repository.go
index 3aa593e..637b676 100644
--- a/x509/revoking/repository.go
+++ b/x509/revoking/repository.go
@@ -1,7 +1,12 @@
 package revoking
 
+import (
+	"crypto/x509/pkix"
+)
+
 // A Repository for storing certificate status information
 type Repository interface {
 	// StoreRevocation stores information about a revoked certificate.
-	StoreRevocation(*CertificateRevoked) error
+	StoreRevocation(*pkix.RevokedCertificate) error
+	RevokedCertificates() ([]pkix.RevokedCertificate, error)
 }
diff --git a/x509/revoking/revoking.go b/x509/revoking/revoking.go
index b3b61c5..de3a394 100644
--- a/x509/revoking/revoking.go
+++ b/x509/revoking/revoking.go
@@ -1,17 +1,88 @@
 package revoking
 
 import (
+	"crypto"
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"fmt"
+	"log"
 	"math/big"
+	"strings"
 	"time"
 )
 
+var OidCRLReason = asn1.ObjectIdentifier{2, 5, 29, 21}
+
+type CRLReason int
+
+// CRL reason codes as defined in RFC 5280 section 5.3.1
+const (
+	CRLReasonUnspecified          CRLReason = 0
+	CRLReasonKeyCompromise        CRLReason = 1
+	CRLReasonCACompromise         CRLReason = 2
+	CRLReasonAffiliationChanged   CRLReason = 3
+	CRLReasonSuperseded           CRLReason = 4
+	CRLReasonCessationOfOperation CRLReason = 5
+	CRLReasonCertificateHold      CRLReason = 6
+	CRLReasonRemoveFromCRL        CRLReason = 8
+	CRLReasonPrivilegeWithdrawn   CRLReason = 9
+	CRLReasonAACompromise         CRLReason = 10
+)
+
+var crlReasonNames = map[CRLReason]string{
+	CRLReasonUnspecified:          "unspecified",
+	CRLReasonKeyCompromise:        "keyCompromise",
+	CRLReasonCACompromise:         "CACompromise",
+	CRLReasonAffiliationChanged:   "affiliationChanged",
+	CRLReasonSuperseded:           "superseded",
+	CRLReasonCessationOfOperation: "cessationOfOperation",
+	CRLReasonCertificateHold:      "certificateHold",
+	CRLReasonRemoveFromCRL:        "removeFromCRL",
+	CRLReasonPrivilegeWithdrawn:   "privilegeWithdrawn",
+	CRLReasonAACompromise:         "AACompromise",
+}
+
+func (r CRLReason) String() string {
+	if reason, ok := crlReasonNames[r]; ok {
+		return reason
+	}
+
+	return crlReasonNames[CRLReasonUnspecified]
+}
+
+func (r CRLReason) BuildExtension() pkix.Extension {
+	extBytes, err := asn1.Marshal(r)
+	if err != nil {
+		// we can panic here because all values of CRLReason must be ASN.1 marshal-able
+		log.Panicf("could not marshal revocation reason: %v", err)
+	}
+
+	return pkix.Extension{Id: OidCRLReason, Value: extBytes}
+}
+
+// ParseReason takes a reason string and performs a case-insensitive match to a reason code
+func ParseReason(rs string) CRLReason {
+	for key, name := range crlReasonNames {
+		if strings.EqualFold(name, rs) {
+			return key
+		}
+	}
+
+	return CRLReasonUnspecified
+}
+
 type X509Revoking struct {
-	repository Repository
+	repository   Repository
+	crlAlgorithm x509.SignatureAlgorithm
+	crlIssuer    *x509.Certificate
+	signer       crypto.Signer
 }
 
 type RevokeCertificate struct {
 	serialNumber *big.Int
-	reason       string
+	reason       CRLReason
 }
 
 type CertificateRevoked struct {
@@ -20,13 +91,15 @@ type CertificateRevoked struct {
 	reason         string
 }
 
-type CRLInformation struct{}
+type CRLInformation struct {
+	CRL []byte // DER encoded CRL
+}
 
-func (r *X509Revoking) Revoke(revokeCertificate *RevokeCertificate) (*CertificateRevoked, error) {
-	revoked := &CertificateRevoked{
-		serialNumber:   revokeCertificate.serialNumber,
-		revocationTime: time.Now(),
-		reason:         revokeCertificate.reason,
+func (r *X509Revoking) Revoke(revokeCertificate *RevokeCertificate) (*pkix.RevokedCertificate, error) {
+	revoked := &pkix.RevokedCertificate{
+		SerialNumber:   revokeCertificate.serialNumber,
+		RevocationTime: time.Now(),
+		Extensions:     []pkix.Extension{revokeCertificate.reason.BuildExtension()},
 	}
 
 	if err := r.repository.StoreRevocation(revoked); err != nil {
@@ -37,21 +110,27 @@ func (r *X509Revoking) Revoke(revokeCertificate *RevokeCertificate) (*Certificat
 }
 
 func (r *X509Revoking) CreateCRL() (*CRLInformation, error) {
-	return &CRLInformation{}, nil
-}
-
-func (r *CertificateRevoked) SerialNumber() *big.Int {
-	return r.serialNumber
-}
+	revoked, err := r.repository.RevokedCertificates()
+	if err != nil {
+		return nil, fmt.Errorf("could not get revocation information: %w", err)
+	}
 
-func (r *CertificateRevoked) RevocationTime() time.Time {
-	return r.revocationTime
-}
+	list, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+		SignatureAlgorithm:  r.crlAlgorithm,
+		RevokedCertificates: revoked,
+	}, r.crlIssuer, r.signer)
+	if err != nil {
+		return nil, fmt.Errorf("could not sign revocation list: %w", err)
+	}
 
-func (r *CertificateRevoked) Reason() string {
-	return r.reason
+	return &CRLInformation{CRL: list}, nil
 }
 
-func NewX509Revoking(repo Repository) *X509Revoking {
-	return &X509Revoking{repository: repo}
+func NewX509Revoking(
+	repo Repository,
+	crlAlgorithm x509.SignatureAlgorithm,
+	issuer *x509.Certificate,
+	signer crypto.Signer,
+) *X509Revoking {
+	return &X509Revoking{repository: repo, crlAlgorithm: crlAlgorithm, crlIssuer: issuer, signer: signer}
 }
diff --git a/x509/revoking/revoking_test.go b/x509/revoking/revoking_test.go
index ea8159f..4937239 100644
--- a/x509/revoking/revoking_test.go
+++ b/x509/revoking/revoking_test.go
@@ -2,8 +2,13 @@ package revoking
 
 import (
 	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
 	"math/big"
+	rand2 "math/rand"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -12,25 +17,54 @@ type testRepo struct {
 	revoked []big.Int
 }
 
-func (t *testRepo) StoreRevocation(revoked *CertificateRevoked) error {
-	t.revoked = append(t.revoked, *revoked.serialNumber)
+func (t *testRepo) RevokedCertificates() ([]pkix.RevokedCertificate, error) {
+	result := make([]pkix.RevokedCertificate, len(t.revoked))
+
+	for i, s := range t.revoked {
+		result[i] = pkix.RevokedCertificate{
+			SerialNumber:   &s,
+			RevocationTime: time.Now(),
+		}
+	}
+
+	return result, nil
+}
+
+func (t *testRepo) StoreRevocation(revoked *pkix.RevokedCertificate) error {
+	t.revoked = append(t.revoked, *revoked.SerialNumber)
 	return nil
 }
 
 func TestRevoking(t *testing.T) {
 	testRepository := testRepo{revoked: make([]big.Int, 0)}
-	r := NewX509Revoking(&testRepository)
+
+	caKey, err := rsa.GenerateKey(rand.Reader, 3072)
+	if err != nil {
+		t.Fatalf("could not generate key pair: %v", err)
+	}
+	caTemplate := &x509.Certificate{Subject: pkix.Name{CommonName: "Test CA"}, SerialNumber: big.NewInt(rand2.Int63())}
+
+	certificateBytes, err := x509.CreateCertificate(rand.Reader, caTemplate, caTemplate, caKey.Public(), caKey)
+	if err != nil {
+		t.Fatalf("could not self-sign CA certificate: %v", err)
+	}
+	caCertificate, err := x509.ParseCertificate(certificateBytes)
+	if err != nil {
+		t.Fatalf("could not create test CA certificate: %v", err)
+	}
+
+	r := NewX509Revoking(&testRepository, x509.ECDSAWithSHA256, caCertificate, caKey)
 
 	serial, err := rand.Int(rand.Reader, new(big.Int).Lsh(big.NewInt(1), 128))
 	if err != nil {
 		t.Errorf("could not create random serial: %v", err)
 	}
 
-	revoke, err := r.Revoke(&RevokeCertificate{serialNumber: serial, reason: "for testing"})
+	revoke, err := r.Revoke(&RevokeCertificate{serialNumber: serial, reason: CRLReasonKeyCompromise})
 	assert.NoError(t, err)
 
-	assert.Equal(t, "for testing", revoke.reason)
-	assert.Equal(t, serial, revoke.serialNumber)
+	assert.Equal(t, CRLReasonKeyCompromise.BuildExtension(), revoke.Extensions[0])
+	assert.Equal(t, serial, revoke.SerialNumber)
 
 	assert.Contains(t, testRepository.revoked, *serial)
 }
diff --git a/x509/signing/repository.go b/x509/signing/repository.go
index 37cf7f3..c294f97 100644
--- a/x509/signing/repository.go
+++ b/x509/signing/repository.go
@@ -1,5 +1,7 @@
 package signing
 
+import "crypto/x509"
+
 type Repository interface {
-	StoreCertificate(*CertificateSigned) error
+	StoreCertificate(certificate *x509.Certificate) error
 }
diff --git a/x509/signing/signer.go b/x509/signing/signer.go
index 20f8676..0adfe94 100644
--- a/x509/signing/signer.go
+++ b/x509/signing/signer.go
@@ -7,36 +7,12 @@ import (
 )
 
 type SignerRequest struct {
-	csr                *x509.CertificateRequest
-	subjectDN          pkix.Name
-	emails             []string
-	dnsNames           []string
-	duration           time.Duration
-	signatureAlgorithm x509.SignatureAlgorithm
-}
-
-func (s *SignerRequest) SignatureAlgorithm() x509.SignatureAlgorithm {
-	return s.signatureAlgorithm
-}
-
-func (s *SignerRequest) Duration() time.Duration {
-	return s.duration
-}
-
-func (s *SignerRequest) DnsNames() []string {
-	return s.dnsNames
-}
-
-func (s *SignerRequest) Emails() []string {
-	return s.emails
-}
-
-func (s *SignerRequest) Csr() *x509.CertificateRequest {
-	return s.csr
-}
-
-func (s *SignerRequest) SubjectDN() pkix.Name {
-	return s.subjectDN
+	CSR                *x509.CertificateRequest
+	SubjectDN          pkix.Name
+	Emails             []string
+	DnsNames           []string
+	Duration           time.Duration
+	SignatureAlgorithm x509.SignatureAlgorithm
 }
 
 func NewSignerRequest(
@@ -47,19 +23,19 @@ func NewSignerRequest(
 	signatureAlgorithm x509.SignatureAlgorithm,
 ) *SignerRequest {
 	return &SignerRequest{
-		csr: csr,
-		subjectDN: subjectDN,
-		emails: emails,
-		dnsNames: dnsNames,
-		duration: duration,
-		signatureAlgorithm: signatureAlgorithm,
+		CSR:                csr,
+		SubjectDN:          subjectDN,
+		Emails:             emails,
+		DnsNames:           dnsNames,
+		Duration:           duration,
+		SignatureAlgorithm: signatureAlgorithm,
 	}
 }
 
-type SignerResponse interface {
-	Certificate() *x509.Certificate
+type SignerResponse struct {
+	Certificate *x509.Certificate
 }
 
 type Signer interface {
-	SignCertificate(*SignerRequest) (SignerResponse, error)
+	SignCertificate(*SignerRequest) (*SignerResponse, error)
 }
diff --git a/x509/signing/signing.go b/x509/signing/signing.go
index 0b08883..3ca385d 100644
--- a/x509/signing/signing.go
+++ b/x509/signing/signing.go
@@ -73,15 +73,10 @@ func (x *X509Signing) Sign(signingRequest *RequestSignature) (*CertificateSigned
 		return nil, err
 	}
 
-	result := NewCertificateSigned(certificateFromSigner)
-	err = x.repo.StoreCertificate(result)
+	err = x.repo.StoreCertificate(certificateFromSigner.Certificate)
 	if err != nil {
 		return nil, err
 	}
 
-	return result, nil
-}
-
-func NewCertificateSigned(signed SignerResponse) *CertificateSigned {
-	return &CertificateSigned{certificate: signed.Certificate()}
+	return &CertificateSigned{certificate: certificateFromSigner.Certificate}, nil
 }
diff --git a/x509/signing/signing_test.go b/x509/signing/signing_test.go
index 3a9fee4..394a8d7 100644
--- a/x509/signing/signing_test.go
+++ b/x509/signing/signing_test.go
@@ -19,9 +19,8 @@ type testRepo struct {
 	certs map[string]x509.Certificate
 }
 
-func (r *testRepo) StoreCertificate(c *signing.CertificateSigned) error {
-	cert := c.Certificate()
-	r.certs[cert.SerialNumber.Text(16)] = *cert
+func (r *testRepo) StoreCertificate(certificate *x509.Certificate) error {
+	r.certs[certificate.SerialNumber.Text(16)] = *certificate
 	return nil
 }
 
@@ -30,32 +29,24 @@ type testSigner struct {
 	certificate *x509.Certificate
 }
 
-type testSignerResponse struct {
-	certificate *x509.Certificate
-}
-
-func (t testSignerResponse) Certificate() *x509.Certificate {
-	return t.certificate
-}
-
-func newTestSignerResponse(certificate *x509.Certificate) *testSignerResponse {
-	return &testSignerResponse{certificate: certificate}
+func newTestSignerResponse(certificate *x509.Certificate) *signing.SignerResponse {
+	return &signing.SignerResponse{Certificate: certificate}
 }
 
-func (s *testSigner) SignCertificate(request *signing.SignerRequest) (signing.SignerResponse, error) {
+func (s *testSigner) SignCertificate(request *signing.SignerRequest) (*signing.SignerResponse, error) {
 	startDate := time.Now().Add(-1 * time.Minute)
 	template := &x509.Certificate{
-		Subject:            request.SubjectDN(),
+		Subject:            request.SubjectDN,
 		SerialNumber:       big.NewInt(rand2.Int63()),
-		EmailAddresses:     request.Emails(),
+		EmailAddresses:     request.Emails,
 		NotBefore:          startDate,
-		NotAfter:           startDate.Add(request.Duration()),
+		NotAfter:           startDate.Add(request.Duration),
 		KeyUsage:           x509.KeyUsageDigitalSignature | x509.KeyUsageDataEncipherment,
 		ExtKeyUsage:        []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth, x509.ExtKeyUsageEmailProtection},
-		SignatureAlgorithm: request.SignatureAlgorithm(),
+		SignatureAlgorithm: request.SignatureAlgorithm,
 	}
 
-	certBytes, err := x509.CreateCertificate(rand.Reader, template, s.certificate, request.Csr().PublicKey, s.key)
+	certBytes, err := x509.CreateCertificate(rand.Reader, template, s.certificate, request.CSR.PublicKey, s.key)
 	if err != nil {
 		return nil, err
 	}