diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index d5e2751..1cffd89 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -88,6 +88,8 @@
 * ``verisign-md2-root.pem`` - A legacy Verisign public root signed using the
   MD2 algorithm. This is a PEM conversion of the `root data`_ in the NSS source
   tree.
+* ``cryptography.io.pem`` - A leaf certificate issued by RapidSSL for the
+  cryptography website.
 
 Custom X.509 Vectors
 ~~~~~~~~~~~~~~~~~~~~
@@ -108,6 +110,11 @@
 * ``utf8_common_name.pem`` - An RSA 2048 bit self-signed CA certificate
   generated using OpenSSL that contains a UTF8String common name with the value
   "We heart UTF8!™".
+* ``two_basic_constraints.pem`` - An RSA 2048 bit self-signed certificate
+  containing two basic constraints extensions.
+* ``basic_constraints_not_critical.pem`` - An RSA 2048 bit self-signed
+  certificate containing a basic constraints extension that is not marked as
+  critical.
 
 Custom X.509 Request Vectors
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/vectors/cryptography_vectors/x509/cryptography.io.pem b/vectors/cryptography_vectors/x509/cryptography.io.pem
new file mode 100644
index 0000000..e13b8b5
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/cryptography.io.pem
@@ -0,0 +1,33 @@
+-----BEGIN CERTIFICATE-----
+MIIFvTCCBKWgAwIBAgICPyAwDQYJKoZIhvcNAQELBQAwRzELMAkGA1UEBhMCVVMx
+FjAUBgNVBAoTDUdlb1RydXN0IEluYy4xIDAeBgNVBAMTF1JhcGlkU1NMIFNIQTI1
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+Xlt2dp2nDQuwGyK2vB7dMfKnQAkxwq1sYUXznB8i0IhhCAoXp01QGPKq51YoIlnF
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+GVI9+0lAFwxOUnOnwsoI40iOoxjLMGB+CgFLKCGUcWxP
+-----END CERTIFICATE-----
diff --git a/vectors/cryptography_vectors/x509/custom/basic_constraints_not_critical.pem b/vectors/cryptography_vectors/x509/custom/basic_constraints_not_critical.pem
new file mode 100644
index 0000000..c3ff0bc
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/custom/basic_constraints_not_critical.pem
@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----
+MIIC7DCCAdSgAwIBAgITBmYB+SFPEZRZNNeTT0olHN1YhjANBgkqhkiG9w0BAQUF
+ADApMRgwFgYDVQQDDA9jcnlwdG9ncmFwaHkuaW8xDTALBgNVBAoMBFB5Q0EwHhcN
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+7OvphkJwAA3tSxuil8G9I6WIinEdiRifxplhR6LbI2w=
+-----END CERTIFICATE-----
diff --git a/vectors/cryptography_vectors/x509/custom/two_basic_constraints.pem b/vectors/cryptography_vectors/x509/custom/two_basic_constraints.pem
new file mode 100644
index 0000000..3ecd56c
--- /dev/null
+++ b/vectors/cryptography_vectors/x509/custom/two_basic_constraints.pem
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----
+MIIDBjCCAe6gAwIBAgITBmYA9IeUP5+hhum5bshgK94QSDANBgkqhkiG9w0BAQUF
+ADApMRgwFgYDVQQDDA9jcnlwdG9ncmFwaHkuaW8xDTALBgNVBAoMBFB5Q0EwHhcN
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+eWLyMsYlzr+ksA==
+-----END CERTIFICATE-----