diff --git a/src/database.cc b/src/database.cc
index 7904b69..297dc40 100644
--- a/src/database.cc
+++ b/src/database.cc
@@ -28,7 +28,13 @@
 #include <botan/botan.h>
 #include <botan/rsa.h>
 #include <botan/pem.h>
-#include <botan/look_pk.h>
+#include <botan/x509_key.h>
+
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+  #include <botan/pubkey.h>
+#else
+  #include <botan/look_pk.h>
+#endif
 #include "lazy_rng.hh"
 
 #include <sqlite3.h>
@@ -3428,17 +3434,27 @@ database::encrypt_rsa(key_id const & pub_id,
   rsa_pub_key pub;
   get_key(pub_id, pub);
 
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+  Botan::DataSource_Memory pub_block(
+    (reinterpret_cast<Botan::byte const *>(pub().data())), pub().size());
+  shared_ptr<X509_PublicKey> x509_key(Botan::X509::load_key(pub_block));
+#else
   SecureVector<Botan::byte> pub_block
     (reinterpret_cast<Botan::byte const *>(pub().data()), pub().size());
 
   shared_ptr<X509_PublicKey> x509_key(Botan::X509::load_key(pub_block));
+#endif
   shared_ptr<RSA_PublicKey> pub_key
     = dynamic_pointer_cast<RSA_PublicKey>(x509_key);
   if (!pub_key)
     throw recoverable_failure(origin::system,
                               "Failed to get RSA encrypting key");
 
-  SecureVector<Botan::byte> ct;
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+     std::vector<Botan::byte> ct;
+#else
+     SecureVector<Botan::byte> ct;
+#endif
 
 #if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,5)
   PK_Encryptor_EME encryptor(*pub_key, "EME1(SHA-1)");
@@ -3462,7 +3478,11 @@ database::encrypt_rsa(key_id const & pub_id,
 #endif
 
   ciphertext = rsa_oaep_sha_data(
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+    string(reinterpret_cast<char const *>(ct.data()), ct.size()),
+#else
     string(reinterpret_cast<char const *>(ct.begin()), ct.size()),
+#endif
     origin::database);
 }
 
@@ -3487,10 +3507,10 @@ database::check_signature(key_id const & id,
         return cert_unknown;
 
       get_key(id, pub);
-      SecureVector<Botan::byte> pub_block
-        (reinterpret_cast<Botan::byte const *>(pub().data()), pub().size());
+      Botan::DataSource_Memory pub_block(
+        (reinterpret_cast<Botan::byte const *>(pub().data())), pub().size());
 
-      L(FL("building verifier for %d-byte pub key") % pub_block.size());
+      L(FL("building verifier for %d-byte pub key") % pub().size());
       shared_ptr<X509_PublicKey> x509_key(Botan::X509::load_key(pub_block));
       shared_ptr<RSA_PublicKey> pub_key
         = boost::dynamic_pointer_cast<RSA_PublicKey>(x509_key);
diff --git a/src/gzip.cc b/src/gzip.cc
index 2cfea09..6832e96 100644
--- a/src/gzip.cc
+++ b/src/gzip.cc
@@ -38,9 +38,6 @@ class Zlib_Alloc_Info
    {
    public:
       std::map<void*, u32bit> current_allocs;
-      Allocator* alloc;
-
-      Zlib_Alloc_Info() { alloc = Allocator::get(false); }
    };
 
 /*************************************************
@@ -49,7 +46,7 @@ class Zlib_Alloc_Info
 void* zlib_malloc(void* info_ptr, unsigned int n, unsigned int size)
    {
    Zlib_Alloc_Info* info = static_cast<Zlib_Alloc_Info*>(info_ptr);
-   void* ptr = info->alloc->allocate(n * size);
+   void* ptr = calloc(n, size);
    info->current_allocs[ptr] = n * size;
    return ptr;
    }
@@ -63,7 +60,8 @@ void zlib_free(void* info_ptr, void* ptr)
    std::map<void*, u32bit>::const_iterator i = info->current_allocs.find(ptr);
    if(i == info->current_allocs.end())
       throw Invalid_Argument("zlib_free: Got pointer not allocated by us");
-   info->alloc->deallocate(ptr, i->second);
+   memset(ptr, 0, i->second);
+   free(ptr);
    }
 }
 
@@ -110,7 +108,7 @@ Gzip_Compression::Gzip_Compression(u32bit l) :
    if(deflateInit2(&(zlib->stream), level, Z_DEFLATED, -15, 8, Z_DEFAULT_STRATEGY) != Z_OK)
       {
       delete zlib; zlib = 0;
-      throw Memory_Exhaustion();
+      throw std::bad_alloc();
       }
    }
 
@@ -148,12 +146,12 @@ void Gzip_Compression::write(const byte input[], filter_length_t length)
 
    while(zlib->stream.avail_in != 0)
       {
-      zlib->stream.next_out = (Bytef*)buffer.begin();
+      zlib->stream.next_out = (Bytef*)&buffer[0];
       zlib->stream.avail_out = buffer.size();
       int rc = deflate(&(zlib->stream), Z_NO_FLUSH);
       if (rc != Z_OK && rc != Z_STREAM_END)
          throw Invalid_State("Internal error in Gzip_Compression deflate.");
-      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
+      send(&buffer[0], buffer.size() - zlib->stream.avail_out);
       }
    }
 
@@ -168,12 +166,12 @@ void Gzip_Compression::end_msg()
    int rc = Z_OK;
    while(rc != Z_STREAM_END)
       {
-      zlib->stream.next_out = (Bytef*)buffer.begin();
+      zlib->stream.next_out = (Bytef*)&buffer[0];
       zlib->stream.avail_out = buffer.size();
       rc = deflate(&(zlib->stream), Z_FINISH);
       if (rc != Z_OK && rc != Z_STREAM_END)
          throw Invalid_State("Internal error in Gzip_Compression finishing deflate.");
-      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
+      send(&buffer[0], buffer.size() - zlib->stream.avail_out);
       }
 
    pipe.end_msg();
@@ -206,19 +204,19 @@ void Gzip_Compression::put_footer()
    SecureVector<byte> buf(4);
    SecureVector<byte> tmpbuf(4);
 
-   pipe.read(tmpbuf.begin(), tmpbuf.size(), Pipe::LAST_MESSAGE);
+   pipe.read(&tmpbuf[0], tmpbuf.size(), Pipe::LAST_MESSAGE);
 
    // CRC32 is the reverse order to what gzip expects.
    for (int i = 0; i < 4; i++)
       buf[3-i] = tmpbuf[i];
 
-   send(buf.begin(), buf.size());
+   send(&buf[0], buf.size());
 
    // Length - LSB first
    for (int i = 0; i < 4; i++)
       buf[3-i] = get_byte(i, count);
 
-   send(buf.begin(), buf.size());
+   send(&buf[0], buf.size());
    }
 
 /*************************************************
@@ -237,7 +235,7 @@ Gzip_Decompression::Gzip_Decompression() : buffer(DEFAULT_BUFFERSIZE),
    if(inflateInit2(&(zlib->stream), -15) != Z_OK)
       {
       delete zlib; zlib = 0;
-      throw Memory_Exhaustion();
+      throw std::bad_alloc();
       }
    }
 
@@ -307,7 +305,7 @@ void Gzip_Decompression::write(const byte input[], filter_length_t length)
 
    while(zlib->stream.avail_in != 0)
       {
-      zlib->stream.next_out = (Bytef*)buffer.begin();
+      zlib->stream.next_out = (Bytef*)&buffer[0];
       zlib->stream.avail_out = buffer.size();
 
       int rc = inflate(&(zlib->stream), Z_SYNC_FLUSH);
@@ -318,11 +316,11 @@ void Gzip_Decompression::write(const byte input[], filter_length_t length)
          if(rc == Z_NEED_DICT)
             throw Decoding_Error("Gzip_Decompression: Need preset dictionary");
          if(rc == Z_MEM_ERROR)
-            throw Memory_Exhaustion();
+            throw std::bad_alloc();
          throw Decoding_Error("Gzip_Decompression: Unknown decompress error");
          }
-      send(buffer.begin(), buffer.size() - zlib->stream.avail_out);
-      pipe.write(buffer.begin(), buffer.size() - zlib->stream.avail_out);
+      send(&buffer[0], buffer.size() - zlib->stream.avail_out);
+      pipe.write(&buffer[0], buffer.size() - zlib->stream.avail_out);
       datacount += buffer.size() - zlib->stream.avail_out;
 
       // Reached the end - we now need to check the footer
@@ -378,13 +376,15 @@ void Gzip_Decompression::check_footer()
    // 4 byte CRC32, and 4 byte length field
    SecureVector<byte> buf(4);
    SecureVector<byte> tmpbuf(4);
-   pipe.read(tmpbuf.begin(), tmpbuf.size(), Pipe::LAST_MESSAGE);
+   pipe.read(&tmpbuf[0], tmpbuf.size(), Pipe::LAST_MESSAGE);
 
   // CRC32 is the reverse order to what gzip expects.
   for (int i = 0; i < 4; i++)
      buf[3-i] = tmpbuf[i];
 
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+  tmpbuf.assign(footer.begin(), footer.end());
+#elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
   tmpbuf.resize(4);
   tmpbuf.copy(footer.begin(), 4);
 #else
diff --git a/src/gzip.hh b/src/gzip.hh
index 7f23cb3..a3895fd 100644
--- a/src/gzip.hh
+++ b/src/gzip.hh
@@ -7,6 +7,7 @@
 #ifndef BOTAN_EXT_GZIP_H__
 #define BOTAN_EXT_GZIP_H__
 
+#include <botan/botan.h>
 #include <botan/version.h>
 #include <botan/filter.h>
 #include <botan/pipe.h>
diff --git a/src/key_packet.cc b/src/key_packet.cc
index 3a56c69..e827503 100644
--- a/src/key_packet.cc
+++ b/src/key_packet.cc
@@ -15,6 +15,8 @@
 #include <sstream>
 #include <botan/botan.h>
 #include <botan/rsa.h>
+#include <botan/x509_key.h>
+#include <botan/pkcs8.h>
 
 #include "cset.hh"
 #include "constants.hh"
@@ -106,7 +108,7 @@ namespace
     void validate_public_key_data(string const & name, string const & keydata) const
     {
       string decoded = decode_base64_as<string>(keydata, origin::user);
-      Botan::SecureVector<Botan::byte> key_block
+      Botan::DataSource_Memory key_block
         (reinterpret_cast<Botan::byte const *>(decoded.c_str()), decoded.size());
       try
         {
diff --git a/src/key_store.cc b/src/key_store.cc
index 9514180..a93f6c9 100644
--- a/src/key_store.cc
+++ b/src/key_store.cc
@@ -13,7 +13,13 @@
 #include <botan/botan.h>
 #include <botan/rsa.h>
 #include <botan/pem.h>
+#include <botan/pkcs8.h>
+
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+#include <botan/pubkey.h>
+#else
 #include <botan/look_pk.h>
+#endif
 
 #include "char_classifiers.hh"
 #include "key_store.hh"
@@ -53,7 +59,6 @@ using Botan::PKCS8_PrivateKey;
 using Botan::PK_Decryptor;
 using Botan::PK_Signer;
 using Botan::Pipe;
-using Botan::get_pk_decryptor;
 using Botan::get_cipher;
 using Botan::byte;
 
@@ -573,7 +578,9 @@ key_store_state::decrypt_private_key(key_id const & id,
   try // with empty passphrase
     {
       Botan::DataSource_Memory ds(kp.priv());
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+      pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get()));
+#elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
       pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get(), Dummy_UI()));
 #elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
       pkcs8_key.reset(Botan::PKCS8::load_key(ds, lazy_rng::get(), ""));
@@ -581,7 +588,9 @@ key_store_state::decrypt_private_key(key_id const & id,
       pkcs8_key.reset(Botan::PKCS8::load_key(ds, ""));
 #endif
     }
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+  catch (Botan::Exception & e)
+#elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
   catch (Passphrase_Required & e)
 #elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,4)
   catch (Botan::Invalid_Argument & e)
@@ -719,6 +728,9 @@ key_store::create_key_pair(database & db,
     unfiltered_pipe->write(
       Botan::PKCS8::BER_encode(priv, lazy_rng::get(),
                                (*maybe_passphrase)(),
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+                               std::chrono::milliseconds(100),
+#endif
                                "PBE-PKCS5v20(SHA-1,TripleDES/CBC)"));
   else
     unfiltered_pipe->write(Botan::PKCS8::PEM_encode(priv));
@@ -818,6 +830,9 @@ key_store::change_key_passphrase(key_id const & id)
     unfiltered_pipe->write(
       Botan::PKCS8::BER_encode(*priv, lazy_rng::get(),
                                new_phrase(),
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+                               std::chrono::milliseconds(100),
+#endif
                                "PBE-PKCS5v20(SHA-1,TripleDES/CBC)"));
   else
     unfiltered_pipe->write(Botan::PKCS8::PEM_encode(*priv));
@@ -909,10 +924,10 @@ key_store::make_signature(database & db,
     {
       if (agent.connected()) {
         //grab the monotone public key as an RSA_PublicKey
-        SecureVector<byte> pub_block
+        Botan::DataSource_Memory pub_block
           (reinterpret_cast<byte const *>(key.pub().data()),
            key.pub().size());
-        L(FL("make_signature: building %d-byte pub key") % pub_block.size());
+        L(FL("make_signature: building %d-byte pub key") % key.pub().size());
         shared_ptr<X509_PublicKey> x509_key =
           shared_ptr<X509_PublicKey>(Botan::X509::load_key(pub_block));
         shared_ptr<RSA_PublicKey> pub_key =
@@ -938,7 +953,11 @@ key_store::make_signature(database & db,
       || s->ssh_sign_mode == "check"
       || s->ssh_sign_mode == "no")
     {
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+      std::vector<byte> sig;
+#else
       SecureVector<byte> sig;
+#endif
 
       // we permit the user to relax security here, by caching a decrypted key
       // (if they permit it) through the life of a program run. this helps when
@@ -967,7 +986,7 @@ key_store::make_signature(database & db,
                      new PK_Signer(*priv_key, "EMSA3(SHA-1)"));
 #else
           signer = shared_ptr<PK_Signer>(
-                     get_pk_signer(*priv_key, "EMSA3(SHA-1)"));
+                    Botan::get_pk_signer(*priv_key, "EMSA3(SHA-1)"));
 #endif
 
           /* If persist_phrase is true, the RSA_PrivateKey object is
@@ -986,7 +1005,12 @@ key_store::make_signature(database & db,
         reinterpret_cast<byte const *>(tosign.data()),
         tosign.size());
 #endif
+
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+      sig_string = string(reinterpret_cast<char const*>(sig.data()), sig.size());
+#else
       sig_string = string(reinterpret_cast<char const*>(sig.begin()), sig.size());
+#endif
     }
 
   if (s->ssh_sign_mode == "check" && ssh_sig.length() > 0)
@@ -1053,6 +1077,9 @@ key_store::export_key_for_agent(key_id const & id,
     p.write(Botan::PKCS8::PEM_encode(*priv,
                                      lazy_rng::get(),
                                      new_phrase(),
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+                                     std::chrono::milliseconds(100),
+#endif
                                      "PBE-PKCS5v20(SHA-1,TripleDES/CBC)"));
   else
     p.write(Botan::PKCS8::PEM_encode(*priv));
@@ -1101,7 +1128,11 @@ key_store_state::migrate_old_key_pair
   for (;;)
     try
       {
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+        arc4_key.assign(reinterpret_cast<byte const *>(phrase().data()),
+                        reinterpret_cast<byte const *>(phrase().data()) + phrase().size());
+
+#elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
         arc4_key.resize(phrase().size());
         arc4_key.copy(reinterpret_cast<byte const *>(phrase().data()),
                       phrase().size());
@@ -1153,6 +1184,9 @@ key_store_state::migrate_old_key_pair
 #if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,10,0)
   unfiltered_pipe->write(Botan::PKCS8::BER_encode(
     *priv_key, lazy_rng::get(), phrase(),
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+    std::chrono::milliseconds(100),
+#endif
     "PBE-PKCS5v20(SHA-1,TripleDES/CBC)"));
 #else
   Botan::PKCS8::encrypt_key(*priv_key, *unfiltered_pipe,
@@ -1161,6 +1195,9 @@ key_store_state::migrate_old_key_pair
 #endif
                             phrase(),
                             "PBE-PKCS5v20(SHA-1,TripleDES/CBC)",
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+                            std::chrono::milliseconds(100),
+#endif
                             Botan::RAW_BER);
 #endif
   unfiltered_pipe->end_msg();
diff --git a/src/package_full_revision.cc b/src/package_full_revision.cc
index 787875e..36b1201 100644
--- a/src/package_full_revision.cc
+++ b/src/package_full_revision.cc
@@ -4,7 +4,7 @@
 
 
 extern char const package_full_revision_constant[];
-char const package_full_revision_constant[134] = {
+char const package_full_revision_constant[223] = {
 	102, 111, 114, 109, 97, 116, 95, 118, 101, 114, 115, 105, 111, 110, 
 	32, 34, 49, 34, 10, 10, 110, 101, 119, 95, 109, 97, 110, 105, 
 	102, 101, 115, 116, 32, 91, 51, 102, 52, 57, 101, 102, 57, 53, 
@@ -14,5 +14,11 @@ char const package_full_revision_constant[134] = {
 	105, 115, 105, 111, 110, 32, 91, 56, 49, 102, 97, 57, 54, 54, 
 	52, 52, 48, 53, 54, 53, 53, 98, 49, 51, 98, 100, 101, 57, 
 	55, 49, 98, 100, 100, 100, 56, 48, 50, 100, 101, 50, 53, 48, 
-	57, 54, 48, 55, 51, 93, 10, 0
+	57, 54, 48, 55, 51, 93, 10, 10, 32, 32, 71, 101, 110, 101, 
+	114, 97, 116, 101, 100, 32, 102, 114, 111, 109, 32, 100, 97, 116, 
+	97, 32, 99, 97, 99, 104, 101, 100, 32, 105, 110, 32, 116, 104, 
+	101, 32, 100, 105, 115, 116, 114, 105, 98, 117, 116, 105, 111, 110, 
+	59, 10, 32, 32, 102, 117, 114, 116, 104, 101, 114, 32, 99, 104, 
+	97, 110, 103, 101, 115, 32, 109, 97, 121, 32, 104, 97, 118, 101, 
+	32, 98, 101, 101, 110, 32, 109, 97, 100, 101, 46, 10, 0
 };
diff --git a/src/packet.cc b/src/packet.cc
index f592d50..805525b 100644
--- a/src/packet.cc
+++ b/src/packet.cc
@@ -11,6 +11,7 @@
 #include <sstream>
 #include <botan/botan.h>
 #include <botan/rsa.h>
+#include <botan/pkcs8.h>
 
 #include "cset.hh"
 #include "constants.hh"
@@ -156,7 +157,7 @@ namespace
     void validate_public_key_data(string const & name, string const & keydata) const
     {
       string decoded = decode_base64_as<string>(keydata, origin::user);
-      Botan::SecureVector<Botan::byte> key_block
+      Botan::DataSource_Memory key_block
         (reinterpret_cast<Botan::byte const *>(decoded.c_str()), decoded.size());
       try
         {
@@ -175,7 +176,9 @@ namespace
       Botan::DataSource_Memory ds(decoded);
       try
         {
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+          Botan::PKCS8::load_key(ds, lazy_rng::get());
+#elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
           Botan::PKCS8::load_key(ds, lazy_rng::get(), Dummy_UI());
 #elif BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,7)
           Botan::PKCS8::load_key(ds, lazy_rng::get(), string());
@@ -191,7 +194,7 @@ namespace
         }
       // since we do not want to prompt for a password to decode it finally,
       // we ignore all other exceptions
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11) && BOTAN_VERSION_CODE <= BOTAN_VERSION_CODE_FOR(1,11,0)
       catch (Passphrase_Required) {}
 #else
       catch (Botan::Invalid_Argument) {}
@@ -467,7 +470,7 @@ read_packets(istream & in, packet_consumer & cons)
 }
 
 // Dummy User_Interface implementation for Botan
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11) && BOTAN_VERSION_CODE < BOTAN_VERSION_CODE_FOR(1,11,0)
 std::string
 Dummy_UI::get_passphrase(const std::string &, const std::string &,
                          Botan::User_Interface::UI_Result&) const
diff --git a/src/packet.hh b/src/packet.hh
index 3d5c1b5..afa42c6 100644
--- a/src/packet.hh
+++ b/src/packet.hh
@@ -10,7 +10,7 @@
 #ifndef __PACKET_HH__
 #define __PACKET_HH__
 
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11) && BOTAN_VERSION_CODE <= BOTAN_VERSION_CODE_FOR(2,0,0)
 #include <botan/ui.h>
 #endif
 
@@ -88,7 +88,7 @@ struct packet_writer : public packet_consumer
 
 size_t read_packets(std::istream & in, packet_consumer & cons);
 
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,9,11) && BOTAN_VERSION_CODE <= BOTAN_VERSION_CODE_FOR(2,0,0)
 // A helper class implementing Botan::User_Interface - which doesn't really
 // interface with the user, but provides the necessary plumbing for Botan.
 //
diff --git a/src/sha1.cc b/src/sha1.cc
index 5f47f90..d14f94d 100644
--- a/src/sha1.cc
+++ b/src/sha1.cc
@@ -17,7 +17,7 @@
 // Botan 1.7.23+ and 1.8.x specific sha1 benchmarking code uses botan's
 // own timer and measures botan's different SHA1 providers, instead of
 // only measuring one.
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,23)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,23) && BOTAN_VERSION_CODE < BOTAN_VERSION_CODE_FOR(1,11,0)
   #include <botan/libstate.h>
   #include <botan/benchmark.h>
 #endif
@@ -37,7 +37,7 @@ CMD_HIDDEN(benchmark_sha1, "benchmark_sha1", "", CMD_REF(debug), "",
 {
   P(F("Benchmarking botan's SHA-1 core"));
 
-#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,23)
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,7,23) && BOTAN_VERSION_CODE < BOTAN_VERSION_CODE_FOR(1,11,0)
 
   Botan::AutoSeeded_RNG rng;
   Botan::Algorithm_Factory& af =
diff --git a/src/ssh_agent.cc b/src/ssh_agent.cc
index e7c2adb..4b65800 100644
--- a/src/ssh_agent.cc
+++ b/src/ssh_agent.cc
@@ -13,6 +13,7 @@
 #include <boost/shared_ptr.hpp>
 #include <botan/botan.h>
 #include <botan/rsa.h>
+#include <botan/x509_key.h>
 #include <botan/numthry.h>
 
 #include "ssh_agent.hh"
@@ -208,11 +209,20 @@ put_bigint_into_buf(BigInt const & bi, string & buf)
   L(FL("ssh_agent: put_bigint_into_buf: bigint.bytes(): %u, bigint: %s")
     % bi.bytes()
     % bi);
-  SecureVector<Botan::byte> bi_buf = BigInt::encode(bi);
+
   string bi_str;
+
+#if BOTAN_VERSION_CODE >= BOTAN_VERSION_CODE_FOR(1,11,0)
+  std::vector<Botan::byte> bi_buf = BigInt::encode(bi);
+  if (*bi_buf.data() & 0x80)
+    bi_str.append(1, static_cast<char>(0));
+  bi_str.append((char *) bi_buf.data(), bi_buf.size());
+#else
+  SecureVector<Botan::byte> bi_buf = BigInt::encode(bi);
   if (*bi_buf.begin() & 0x80)
     bi_str.append(1, static_cast<char>(0));
   bi_str.append((char *) bi_buf.begin(), bi_buf.size());
+#endif
   put_string_into_buf(bi_str, buf);
   L(FL("ssh_agent: put_bigint_into_buf: buf len now %i") % buf.length());
 }
@@ -385,10 +395,10 @@ bool
 ssh_agent::has_key(const keypair & key)
 {
   //grab the monotone public key as an RSA_PublicKey
-  SecureVector<Botan::byte> pub_block
+  Botan::DataSource_Memory pub_block
     (reinterpret_cast<Botan::byte const *>((key.pub)().data()),
      (key.pub)().size());
-  L(FL("has_key: building %d-byte pub key") % pub_block.size());
+  L(FL("has_key: building %d-byte pub key") % key.pub().size());
   shared_ptr<X509_PublicKey> x509_key =
     shared_ptr<X509_PublicKey>(Botan::X509::load_key(pub_block));
   shared_ptr<RSA_PublicKey> pub_key = 
diff --git a/test/unit/tests/merge_3way.cc b/test/unit/tests/merge_3way.cc
index 09ec4d6..bbfff92 100644
--- a/test/unit/tests/merge_3way.cc
+++ b/test/unit/tests/merge_3way.cc
@@ -17,6 +17,8 @@
 #include "../randomfile.hh"
 #include "../../../src/simplestring_xform.hh"
 
+#include <iostream>
+
 using std::cerr;
 using std::cout;
 using std::stringstream;