diff --git a/src/or/buffers.c b/src/or/buffers.c
index 8b9a53c699..ecaafbba56 100644
--- a/src/or/buffers.c
+++ b/src/or/buffers.c
@@ -914,97 +914,6 @@ fetch_var_cell_from_buf(buf_t *buf, var_cell_t **out, int linkproto)
   return 1;
 }
 
-#ifdef USE_BUFFEREVENTS
-/** Try to read <b>n</b> bytes from <b>buf</b> at <b>pos</b> (which may be
- * NULL for the start of the buffer), copying the data only if necessary.  Set
- * *<b>data_out</b> to a pointer to the desired bytes.  Set <b>free_out</b>
- * to 1 if we needed to malloc *<b>data</b> because the original bytes were
- * noncontiguous; 0 otherwise.  Return the number of bytes actually available
- * at *<b>data_out</b>.
- */
-static ssize_t
-inspect_evbuffer(struct evbuffer *buf, char **data_out, size_t n,
-                 int *free_out, struct evbuffer_ptr *pos)
-{
-  int n_vecs, i;
-
-  if (evbuffer_get_length(buf) < n)
-    n = evbuffer_get_length(buf);
-  if (n == 0)
-    return 0;
-  n_vecs = evbuffer_peek(buf, n, pos, NULL, 0);
-  tor_assert(n_vecs > 0);
-  if (n_vecs == 1) {
-    struct evbuffer_iovec v;
-    i = evbuffer_peek(buf, n, pos, &v, 1);
-    tor_assert(i == 1);
-    *data_out = v.iov_base;
-    *free_out = 0;
-    return v.iov_len;
-  } else {
-    ev_ssize_t copied;
-    *data_out = tor_malloc(n);
-    *free_out = 1;
-    copied = evbuffer_copyout(buf, *data_out, n);
-    tor_assert(copied >= 0 && (size_t)copied == n);
-    return copied;
-  }
-}
-
-/** As fetch_var_cell_from_buf, buf works on an evbuffer. */
-int
-fetch_var_cell_from_evbuffer(struct evbuffer *buf, var_cell_t **out,
-                             int linkproto)
-{
-  char *hdr = NULL;
-  int free_hdr = 0;
-  size_t n;
-  size_t buf_len;
-  uint8_t command;
-  uint16_t cell_length;
-  var_cell_t *cell;
-  int result = 0;
-  const int wide_circ_ids = linkproto >= MIN_LINK_PROTO_FOR_WIDE_CIRC_IDS;
-  const int circ_id_len = get_circ_id_size(wide_circ_ids);
-  const unsigned header_len = get_var_cell_header_size(wide_circ_ids);
-
-  *out = NULL;
-  buf_len = evbuffer_get_length(buf);
-  if (buf_len < header_len)
-    return 0;
-
-  n = inspect_evbuffer(buf, &hdr, header_len, &free_hdr, NULL);
-  tor_assert(n >= header_len);
-
-  command = get_uint8(hdr + circ_id_len);
-  if (!(cell_command_is_var_length(command, linkproto))) {
-    goto done;
-  }
-
-  cell_length = ntohs(get_uint16(hdr + circ_id_len + 1));
-  if (buf_len < (size_t)(header_len+cell_length)) {
-    result = 1; /* Not all here yet. */
-    goto done;
-  }
-
-  cell = var_cell_new(cell_length);
-  cell->command = command;
-  if (wide_circ_ids)
-    cell->circ_id = ntohl(get_uint32(hdr));
-  else
-    cell->circ_id = ntohs(get_uint16(hdr));
-  evbuffer_drain(buf, header_len);
-  evbuffer_remove(buf, cell->payload, cell_length);
-  *out = cell;
-  result = 1;
-
- done:
-  if (free_hdr && hdr)
-    tor_free(hdr);
-  return result;
-}
-#endif
-
 /** Move up to *<b>buf_flushlen</b> bytes from <b>buf_in</b> to
  * <b>buf_out</b>, and modify *<b>buf_flushlen</b> appropriately.
  * Return the number of bytes actually copied.
@@ -1247,94 +1156,6 @@ fetch_from_buf_http(buf_t *buf,
   return 1;
 }
 
-#ifdef USE_BUFFEREVENTS
-/** As fetch_from_buf_http, buf works on an evbuffer. */
-int
-fetch_from_evbuffer_http(struct evbuffer *buf,
-                    char **headers_out, size_t max_headerlen,
-                    char **body_out, size_t *body_used, size_t max_bodylen,
-                    int force_complete)
-{
-  struct evbuffer_ptr crlf, content_length;
-  size_t headerlen, bodylen, contentlen;
-
-  /* Find the first \r\n\r\n in the buffer */
-  crlf = evbuffer_search(buf, "\r\n\r\n", 4, NULL);
-  if (crlf.pos < 0) {
-    /* We didn't find one. */
-    if (evbuffer_get_length(buf) > max_headerlen)
-      return -1; /* Headers too long. */
-    return 0; /* Headers not here yet. */
-  } else if (crlf.pos > (int)max_headerlen) {
-    return -1; /* Headers too long. */
-  }
-
-  headerlen = crlf.pos + 4;  /* Skip over the \r\n\r\n */
-  bodylen = evbuffer_get_length(buf) - headerlen;
-  if (bodylen > max_bodylen)
-    return -1; /* body too long */
-
-  /* Look for the first occurrence of CONTENT_LENGTH insize buf before the
-   * crlfcrlf */
-  content_length = evbuffer_search_range(buf, CONTENT_LENGTH,
-                                         strlen(CONTENT_LENGTH), NULL, &crlf);
-
-  if (content_length.pos >= 0) {
-    /* We found a content_length: parse it and figure out if the body is here
-     * yet. */
-    struct evbuffer_ptr eol;
-    char *data = NULL;
-    int free_data = 0;
-    int n, i;
-    n = evbuffer_ptr_set(buf, &content_length, strlen(CONTENT_LENGTH),
-                         EVBUFFER_PTR_ADD);
-    tor_assert(n == 0);
-    eol = evbuffer_search_eol(buf, &content_length, NULL, EVBUFFER_EOL_CRLF);
-    tor_assert(eol.pos > content_length.pos);
-    tor_assert(eol.pos <= crlf.pos);
-    inspect_evbuffer(buf, &data, eol.pos - content_length.pos, &free_data,
-                         &content_length);
-
-    i = atoi(data);
-    if (free_data)
-      tor_free(data);
-    if (i < 0) {
-      log_warn(LD_PROTOCOL, "Content-Length is less than zero; it looks like "
-               "someone is trying to crash us.");
-      return -1;
-    }
-    contentlen = i;
-    /* if content-length is malformed, then our body length is 0. fine. */
-    log_debug(LD_HTTP,"Got a contentlen of %d.",(int)contentlen);
-    if (bodylen < contentlen) {
-      if (!force_complete) {
-        log_debug(LD_HTTP,"body not all here yet.");
-        return 0; /* not all there yet */
-      }
-    }
-    if (bodylen > contentlen) {
-      bodylen = contentlen;
-      log_debug(LD_HTTP,"bodylen reduced to %d.",(int)bodylen);
-    }
-  }
-
-  if (headers_out) {
-    *headers_out = tor_malloc(headerlen+1);
-    evbuffer_remove(buf, *headers_out, headerlen);
-    (*headers_out)[headerlen] = '\0';
-  }
-  if (body_out) {
-    tor_assert(headers_out);
-    tor_assert(body_used);
-    *body_used = bodylen;
-    *body_out = tor_malloc(bodylen+1);
-    evbuffer_remove(buf, *body_out, bodylen);
-    (*body_out)[bodylen] = '\0';
-  }
-  return 1;
-}
-#endif
-
 /**
  * Wait this many seconds before warning the user about using SOCKS unsafely
  * again (requires that WarnUnsafeSocks is turned on). */
@@ -1454,86 +1275,6 @@ fetch_from_buf_socks(buf_t *buf, socks_request_t *req,
   return res;
 }
 
-#ifdef USE_BUFFEREVENTS
-/* As fetch_from_buf_socks(), but targets an evbuffer instead. */
-int
-fetch_from_evbuffer_socks(struct evbuffer *buf, socks_request_t *req,
-                          int log_sockstype, int safe_socks)
-{
-  char *data;
-  ssize_t n_drain;
-  size_t datalen, buflen, want_length;
-  int res;
-
-  buflen = evbuffer_get_length(buf);
-  if (buflen < 2)
-    return 0;
-
-  {
-    /* See if we can find the socks request in the first chunk of the buffer.
-     */
-    struct evbuffer_iovec v;
-    int i;
-    n_drain = 0;
-    i = evbuffer_peek(buf, -1, NULL, &v, 1);
-    tor_assert(i == 1);
-    data = v.iov_base;
-    datalen = v.iov_len;
-    want_length = 0;
-
-    res = parse_socks(data, datalen, req, log_sockstype,
-                      safe_socks, &n_drain, &want_length);
-
-    if (n_drain < 0)
-      evbuffer_drain(buf, evbuffer_get_length(buf));
-    else if (n_drain > 0)
-      evbuffer_drain(buf, n_drain);
-
-    if (res)
-      return res;
-  }
-
-  /* Okay, the first chunk of the buffer didn't have a complete socks request.
-   * That means that either we don't have a whole socks request at all, or
-   * it's gotten split up.  We're going to try passing parse_socks() bigger
-   * and bigger chunks until either it says "Okay, I got it", or it says it
-   * will need more data than we currently have. */
-
-  /* Loop while we have more data that we haven't given parse_socks() yet. */
-  do {
-    int free_data = 0;
-    const size_t last_wanted = want_length;
-    n_drain = 0;
-    data = NULL;
-    datalen = inspect_evbuffer(buf, &data, want_length, &free_data, NULL);
-
-    want_length = 0;
-    res = parse_socks(data, datalen, req, log_sockstype,
-                      safe_socks, &n_drain, &want_length);
-
-    if (free_data)
-      tor_free(data);
-
-    if (n_drain < 0)
-      evbuffer_drain(buf, evbuffer_get_length(buf));
-    else if (n_drain > 0)
-      evbuffer_drain(buf, n_drain);
-
-    if (res == 0 && n_drain == 0 && want_length <= last_wanted) {
-      /* If we drained nothing, and we didn't ask for more than last time,
-       * then we probably wanted more data than the buffer actually had,
-       * and we're finding out that we're not satisified with it. It's
-       * time to break until we have more data. */
-      break;
-    }
-
-    buflen = evbuffer_get_length(buf);
-  } while (res == 0 && want_length <= buflen && buflen >= 2);
-
-  return res;
-}
-#endif
-
 /** The size of the header of an Extended ORPort message: 2 bytes for
  *  COMMAND, 2 bytes for BODYLEN */
 #define EXT_OR_CMD_HEADER_SIZE 4
@@ -1564,34 +1305,6 @@ fetch_ext_or_command_from_buf(buf_t *buf, ext_or_cmd_t **out)
   return 1;
 }
 
-#ifdef USE_BUFFEREVENTS
-/** Read <b>buf</b>, which should contain an Extended ORPort message
- *  from a transport proxy. If well-formed, create and populate
- *  <b>out</b> with the Extended ORport message. Return 0 if the
- *  buffer was incomplete, 1 if it was well-formed and -1 if we
- *  encountered an error while parsing it.  */
-int
-fetch_ext_or_command_from_evbuffer(struct evbuffer *buf, ext_or_cmd_t **out)
-{
-  char hdr[EXT_OR_CMD_HEADER_SIZE];
-  uint16_t len;
-  size_t buf_len = evbuffer_get_length(buf);
-
-  if (buf_len < EXT_OR_CMD_HEADER_SIZE)
-    return 0;
-  evbuffer_copyout(buf, hdr, EXT_OR_CMD_HEADER_SIZE);
-  len = ntohs(get_uint16(hdr+2));
-  if (buf_len < (unsigned)len + EXT_OR_CMD_HEADER_SIZE)
-    return 0;
-  *out = ext_or_cmd_new(len);
-  (*out)->cmd = ntohs(get_uint16(hdr));
-  (*out)->len = len;
-  evbuffer_drain(buf, EXT_OR_CMD_HEADER_SIZE);
-  evbuffer_remove(buf, (*out)->body, len);
-  return 1;
-}
-#endif
-
 /** Create a SOCKS5 reply message with <b>reason</b> in its REP field and
  * have Tor send it as error response to <b>req</b>.
  */
@@ -2036,34 +1749,6 @@ fetch_from_buf_socks_client(buf_t *buf, int state, char **reason)
   return r;
 }
 
-#ifdef USE_BUFFEREVENTS
-/** As fetch_from_buf_socks_client, buf works on an evbuffer */
-int
-fetch_from_evbuffer_socks_client(struct evbuffer *buf, int state,
-                                 char **reason)
-{
-  ssize_t drain = 0;
-  uint8_t *data;
-  size_t datalen;
-  int r;
-
-  /* Linearize the SOCKS response in the buffer, up to 128 bytes.
-   * (parse_socks_client shouldn't need to see anything beyond that.) */
-  datalen = evbuffer_get_length(buf);
-  if (datalen > MAX_SOCKS_MESSAGE_LEN)
-    datalen = MAX_SOCKS_MESSAGE_LEN;
-  data = evbuffer_pullup(buf, datalen);
-
-  r = parse_socks_client(data, datalen, state, reason, &drain);
-  if (drain > 0)
-    evbuffer_drain(buf, drain);
-  else if (drain < 0)
-    evbuffer_drain(buf, evbuffer_get_length(buf));
-
-  return r;
-}
-#endif
-
 /** Implementation logic for fetch_from_*_socks_client. */
 static int
 parse_socks_client(const uint8_t *data, size_t datalen,
@@ -2194,27 +1879,6 @@ peek_buf_has_control0_command(buf_t *buf)
   return 0;
 }
 
-#ifdef USE_BUFFEREVENTS
-int
-peek_evbuffer_has_control0_command(struct evbuffer *buf)
-{
-  int result = 0;
-  if (evbuffer_get_length(buf) >= 4) {
-    int free_out = 0;
-    char *data = NULL;
-    size_t n = inspect_evbuffer(buf, &data, 4, &free_out, NULL);
-    uint16_t cmd;
-    tor_assert(n >= 4);
-    cmd = ntohs(get_uint16(data+2));
-    if (cmd <= 0x14)
-      result = 1;
-    if (free_out)
-      tor_free(data);
-  }
-  return result;
-}
-#endif
-
 /** Return the index within <b>buf</b> at which <b>ch</b> first appears,
  * or -1 if <b>ch</b> does not appear on buf. */
 static off_t
@@ -2312,93 +1976,14 @@ write_to_buf_zlib(buf_t *buf, tor_zlib_state_t *state,
   return 0;
 }
 
-#ifdef USE_BUFFEREVENTS
-int
-write_to_evbuffer_zlib(struct evbuffer *buf, tor_zlib_state_t *state,
-                       const char *data, size_t data_len,
-                       int done)
-{
-  char *next;
-  size_t old_avail, avail;
-  int over = 0, n;
-  struct evbuffer_iovec vec[1];
-  do {
-    {
-      size_t cap = data_len / 4;
-      if (cap < 128)
-        cap = 128;
-      /* XXXX NM this strategy is fragmentation-prone. We should really have
-       * two iovecs, and write first into the one, and then into the
-       * second if the first gets full. */
-      n = evbuffer_reserve_space(buf, cap, vec, 1);
-      tor_assert(n == 1);
-    }
-
-    next = vec[0].iov_base;
-    avail = old_avail = vec[0].iov_len;
-
-    switch (tor_zlib_process(state, &next, &avail, &data, &data_len, done)) {
-      case TOR_ZLIB_DONE:
-        over = 1;
-        break;
-      case TOR_ZLIB_ERR:
-        return -1;
-      case TOR_ZLIB_OK:
-        if (data_len == 0)
-          over = 1;
-        break;
-      case TOR_ZLIB_BUF_FULL:
-        if (avail) {
-          /* Zlib says we need more room (ZLIB_BUF_FULL).  Start a new chunk
-           * automatically, whether were going to or not. */
-        }
-        break;
-    }
-
-    /* XXXX possible infinite loop on BUF_FULL. */
-    vec[0].iov_len = old_avail - avail;
-    evbuffer_commit_space(buf, vec, 1);
-
-  } while (!over);
-  check();
-  return 0;
-}
-#endif
-
 /** Set *<b>output</b> to contain a copy of the data in *<b>input</b> */
 int
 generic_buffer_set_to_copy(generic_buffer_t **output,
                            const generic_buffer_t *input)
 {
-#ifdef USE_BUFFEREVENTS
-  struct evbuffer_ptr ptr;
-  size_t remaining = evbuffer_get_length(input);
-  if (*output) {
-    evbuffer_drain(*output, evbuffer_get_length(*output));
-  } else {
-    if (!(*output = evbuffer_new()))
-      return -1;
-  }
-  evbuffer_ptr_set((struct evbuffer*)input, &ptr, 0, EVBUFFER_PTR_SET);
-  while (remaining) {
-    struct evbuffer_iovec v[4];
-    int n_used, i;
-    n_used = evbuffer_peek((struct evbuffer*)input, -1, &ptr, v, 4);
-    if (n_used < 0)
-      return -1;
-    for (i=0;i<n_used;++i) {
-      evbuffer_add(*output, v[i].iov_base, v[i].iov_len);
-      tor_assert(v[i].iov_len <= remaining);
-      remaining -= v[i].iov_len;
-      evbuffer_ptr_set((struct evbuffer*)input,
-                       &ptr, v[i].iov_len, EVBUFFER_PTR_ADD);
-    }
-  }
-#else
   if (*output)
     buf_free(*output);
   *output = buf_copy(input);
-#endif
   return 0;
 }
 
diff --git a/src/or/buffers.h b/src/or/buffers.h
index 2b43ea14b1..2b25bc3c07 100644
--- a/src/or/buffers.h
+++ b/src/or/buffers.h
@@ -56,35 +56,6 @@ int peek_buf_has_control0_command(buf_t *buf);
 
 int fetch_ext_or_command_from_buf(buf_t *buf, ext_or_cmd_t **out);
 
-#ifdef USE_BUFFEREVENTS
-int fetch_var_cell_from_evbuffer(struct evbuffer *buf, var_cell_t **out,
-                                 int linkproto);
-int fetch_from_evbuffer_socks(struct evbuffer *buf, socks_request_t *req,
-                              int log_sockstype, int safe_socks);
-int fetch_from_evbuffer_socks_client(struct evbuffer *buf, int state,
-                                     char **reason);
-int fetch_from_evbuffer_http(struct evbuffer *buf,
-                        char **headers_out, size_t max_headerlen,
-                        char **body_out, size_t *body_used, size_t max_bodylen,
-                        int force_complete);
-int peek_evbuffer_has_control0_command(struct evbuffer *buf);
-int write_to_evbuffer_zlib(struct evbuffer *buf, tor_zlib_state_t *state,
-                           const char *data, size_t data_len,
-                           int done);
-int fetch_ext_or_command_from_evbuffer(struct evbuffer *buf,
-                                       ext_or_cmd_t **out);
-#endif
-
-#ifdef USE_BUFFEREVENTS
-#define generic_buffer_new() evbuffer_new()
-#define generic_buffer_len(b) evbuffer_get_length((b))
-#define generic_buffer_add(b,dat,len) evbuffer_add((b),(dat),(len))
-#define generic_buffer_get(b,buf,buflen) evbuffer_remove((b),(buf),(buflen))
-#define generic_buffer_clear(b) evbuffer_drain((b), evbuffer_get_length((b)))
-#define generic_buffer_free(b) evbuffer_free((b))
-#define generic_buffer_fetch_ext_or_cmd(b, out) \
-  fetch_ext_or_command_from_evbuffer((b), (out))
-#else
 #define generic_buffer_new() buf_new()
 #define generic_buffer_len(b) buf_datalen((b))
 #define generic_buffer_add(b,dat,len) write_to_buf((dat),(len),(b))
@@ -93,7 +64,6 @@ int fetch_ext_or_command_from_evbuffer(struct evbuffer *buf,
 #define generic_buffer_free(b) buf_free((b))
 #define generic_buffer_fetch_ext_or_cmd(b, out) \
   fetch_ext_or_command_from_buf((b), (out))
-#endif
 int generic_buffer_set_to_copy(generic_buffer_t **output,
                                const generic_buffer_t *input);
 
diff --git a/src/or/config.c b/src/or/config.c
index 55be06cf00..5a59e2adea 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -1674,17 +1674,6 @@ options_act(const or_options_t *old_options)
   if (accounting_is_enabled(options))
     configure_accounting(time(NULL));
 
-#ifdef USE_BUFFEREVENTS
-  /* If we're using the bufferevents implementation and our rate limits
-   * changed, we need to tell the rate-limiting system about it. */
-  if (!old_options ||
-      old_options->BandwidthRate != options->BandwidthRate ||
-      old_options->BandwidthBurst != options->BandwidthBurst ||
-      old_options->RelayBandwidthRate != options->RelayBandwidthRate ||
-      old_options->RelayBandwidthBurst != options->RelayBandwidthBurst)
-    connection_bucket_init();
-#endif
-
   old_ewma_enabled = cell_ewma_enabled();
   /* Change the cell EWMA settings */
   cell_ewma_set_scale_factor(options, networkstatus_get_latest_consensus());
diff --git a/src/or/connection.c b/src/or/connection.c
index 9eef063f18..9b82e0924f 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -52,10 +52,6 @@
 #include "sandbox.h"
 #include "transports.h"
 
-#ifdef USE_BUFFEREVENTS
-#include <event2/event.h>
-#endif
-
 #ifdef HAVE_PWD_H
 #include <pwd.h>
 #endif
@@ -75,10 +71,8 @@ static void connection_init(time_t now, connection_t *conn, int type,
 static int connection_init_accepted_conn(connection_t *conn,
                           const listener_connection_t *listener);
 static int connection_handle_listener_read(connection_t *conn, int new_type);
-#ifndef USE_BUFFEREVENTS
 static int connection_bucket_should_increase(int bucket,
                                              or_connection_t *conn);
-#endif
 static int connection_finished_flushing(connection_t *conn);
 static int connection_flushed_some(connection_t *conn);
 static int connection_finished_connecting(connection_t *conn);
@@ -236,26 +230,6 @@ conn_state_to_string(int type, int state)
   return buf;
 }
 
-#ifdef USE_BUFFEREVENTS
-/** Return true iff the connection's type is one that can use a
-    bufferevent-based implementation. */
-int
-connection_type_uses_bufferevent(connection_t *conn)
-{
-  switch (conn->type) {
-    case CONN_TYPE_AP:
-    case CONN_TYPE_EXIT:
-    case CONN_TYPE_DIR:
-    case CONN_TYPE_CONTROL:
-    case CONN_TYPE_OR:
-    case CONN_TYPE_EXT_OR:
-      return 1;
-    default:
-      return 0;
-  }
-}
-#endif
-
 /** Allocate and return a new dir_connection_t, initialized as by
  * connection_init(). */
 dir_connection_t *
@@ -427,13 +401,11 @@ connection_init(time_t now, connection_t *conn, int type, int socket_family)
 
   conn->type = type;
   conn->socket_family = socket_family;
-#ifndef USE_BUFFEREVENTS
   if (!connection_is_listener(conn)) {
     /* listeners never use their buf */
     conn->inbuf = buf_new();
     conn->outbuf = buf_new();
   }
-#endif
 
   conn->timestamp_created = now;
   conn->timestamp_lastread = now;
@@ -645,13 +617,6 @@ connection_free_(connection_t *conn)
     tor_free(TO_OR_CONN(conn)->ext_or_transport);
   }
 
-#ifdef USE_BUFFEREVENTS
-  if (conn->type == CONN_TYPE_OR && TO_OR_CONN(conn)->bucket_cfg) {
-    ev_token_bucket_cfg_free(TO_OR_CONN(conn)->bucket_cfg);
-    TO_OR_CONN(conn)->bucket_cfg = NULL;
-  }
-#endif
-
   memwipe(mem, 0xCC, memlen); /* poison memory */
   tor_free(mem);
 }
@@ -2694,21 +2659,15 @@ connection_is_rate_limited(connection_t *conn)
     return 1;
 }
 
-#ifdef USE_BUFFEREVENTS
-static struct bufferevent_rate_limit_group *global_rate_limit = NULL;
-#else
-
 /** Did either global write bucket run dry last second? If so,
  * we are likely to run dry again this second, so be stingy with the
  * tokens we just put in. */
 static int write_buckets_empty_last_second = 0;
-#endif
 
 /** How many seconds of no active local circuits will make the
  * connection revert to the "relayed" bandwidth class? */
 #define CLIENT_IDLE_TIME_FOR_PRIORITY 30
 
-#ifndef USE_BUFFEREVENTS
 /** Return 1 if <b>conn</b> should use tokens from the "relayed"
  * bandwidth rates, else 0. Currently, only OR conns with bandwidth
  * class 1, and directory conns that are serving data out, count.
@@ -2820,20 +2779,6 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
   return connection_bucket_round_robin(base, priority,
                                        global_bucket, conn_bucket);
 }
-#else
-static ssize_t
-connection_bucket_read_limit(connection_t *conn, time_t now)
-{
-  (void) now;
-  return bufferevent_get_max_to_read(conn->bufev);
-}
-ssize_t
-connection_bucket_write_limit(connection_t *conn, time_t now)
-{
-  (void) now;
-  return bufferevent_get_max_to_write(conn->bufev);
-}
-#endif
 
 /** Return 1 if the global write buckets are low enough that we
  * shouldn't send <b>attempt</b> bytes of low-priority directory stuff
@@ -2857,12 +2802,8 @@ connection_bucket_write_limit(connection_t *conn, time_t now)
 int
 global_write_bucket_low(connection_t *conn, size_t attempt, int priority)
 {
-#ifdef USE_BUFFEREVENTS
-  ssize_t smaller_bucket = bufferevent_get_max_to_write(conn->bufev);
-#else
   int smaller_bucket = global_write_bucket < global_relayed_write_bucket ?
                        global_write_bucket : global_relayed_write_bucket;
-#endif
   if (authdir_mode(get_options()) && priority>1)
     return 0; /* there's always room to answer v2 if we're an auth dir */
 
@@ -2872,10 +2813,8 @@ global_write_bucket_low(connection_t *conn, size_t attempt, int priority)
   if (smaller_bucket < (int)attempt)
     return 1; /* not enough space no matter the priority */
 
-#ifndef USE_BUFFEREVENTS
   if (write_buckets_empty_last_second)
     return 1; /* we're already hitting our limits, no more please */
-#endif
 
   if (priority == 1) { /* old-style v1 query */
     /* Could we handle *two* of these requests within the next two seconds? */
@@ -2923,29 +2862,6 @@ record_num_bytes_transferred_impl(connection_t *conn,
     rep_hist_note_exit_bytes(conn->port, num_written, num_read);
 }
 
-#ifdef USE_BUFFEREVENTS
-/** Wrapper around fetch_from_(buf/evbuffer)_socks_client: see those functions
- * for documentation of its behavior. */
-static void
-record_num_bytes_transferred(connection_t *conn,
-                             time_t now, size_t num_read, size_t num_written)
-{
-  /* XXXX check if this is necessary */
-  if (num_written >= INT_MAX || num_read >= INT_MAX) {
-    log_err(LD_BUG, "Value out of range. num_read=%lu, num_written=%lu, "
-             "connection type=%s, state=%s",
-             (unsigned long)num_read, (unsigned long)num_written,
-             conn_type_to_string(conn->type),
-             conn_state_to_string(conn->type, conn->state));
-    if (num_written >= INT_MAX) num_written = 1;
-    if (num_read >= INT_MAX) num_read = 1;
-    tor_fragile_assert();
-  }
-
-  record_num_bytes_transferred_impl(conn,now,num_read,num_written);
-}
-#endif
-
 /** Helper: convert given <b>tvnow</b> time value to milliseconds since
  * midnight. */
 static uint32_t
@@ -2990,7 +2906,6 @@ connection_buckets_note_empty_ts(uint32_t *timestamp_var,
     *timestamp_var = msec_since_midnight(tvnow);
 }
 
-#ifndef USE_BUFFEREVENTS
 /** Last time at which the global or relay buckets were emptied in msec
  * since midnight. */
 static uint32_t global_relayed_read_emptied = 0,
@@ -3321,92 +3236,6 @@ connection_bucket_should_increase(int bucket, or_connection_t *conn)
 
   return 1;
 }
-#else
-static void
-connection_buckets_decrement(connection_t *conn, time_t now,
-                             size_t num_read, size_t num_written)
-{
-  (void) conn;
-  (void) now;
-  (void) num_read;
-  (void) num_written;
-  /* Libevent does this for us. */
-}
-
-void
-connection_bucket_refill(int seconds_elapsed, time_t now)
-{
-  (void) seconds_elapsed;
-  (void) now;
-  /* Libevent does this for us. */
-}
-void
-connection_bucket_init(void)
-{
-  const or_options_t *options = get_options();
-  const struct timeval *tick = tor_libevent_get_one_tick_timeout();
-  struct ev_token_bucket_cfg *bucket_cfg;
-
-  uint64_t rate, burst;
-  if (options->RelayBandwidthRate) {
-    rate = options->RelayBandwidthRate;
-    burst = options->RelayBandwidthBurst;
-  } else {
-    rate = options->BandwidthRate;
-    burst = options->BandwidthBurst;
-  }
-
-  /* This can't overflow, since TokenBucketRefillInterval <= 1000,
-   * and rate started out less than INT32_MAX. */
-  rate = (rate * options->TokenBucketRefillInterval) / 1000;
-
-  bucket_cfg = ev_token_bucket_cfg_new((uint32_t)rate, (uint32_t)burst,
-                                       (uint32_t)rate, (uint32_t)burst,
-                                       tick);
-
-  if (!global_rate_limit) {
-    global_rate_limit =
-      bufferevent_rate_limit_group_new(tor_libevent_get_base(), bucket_cfg);
-  } else {
-    bufferevent_rate_limit_group_set_cfg(global_rate_limit, bucket_cfg);
-  }
-  ev_token_bucket_cfg_free(bucket_cfg);
-}
-
-void
-connection_get_rate_limit_totals(uint64_t *read_out, uint64_t *written_out)
-{
-  if (global_rate_limit == NULL) {
-    *read_out = *written_out = 0;
-  } else {
-    bufferevent_rate_limit_group_get_totals(
-      global_rate_limit, read_out, written_out);
-  }
-}
-
-/** Perform whatever operations are needed on <b>conn</b> to enable
- * rate-limiting. */
-void
-connection_enable_rate_limiting(connection_t *conn)
-{
-  if (conn->bufev) {
-    if (!global_rate_limit)
-      connection_bucket_init();
-    tor_add_bufferevent_to_rate_limit_group(conn->bufev, global_rate_limit);
-  }
-}
-
-static void
-connection_consider_empty_write_buckets(connection_t *conn)
-{
-  (void) conn;
-}
-static void
-connection_consider_empty_read_buckets(connection_t *conn)
-{
-  (void) conn;
-}
-#endif
 
 /** Read bytes from conn-\>s and process them.
  *
@@ -3737,161 +3566,6 @@ connection_read_to_buf(connection_t *conn, ssize_t *max_to_read,
   return 0;
 }
 
-#ifdef USE_BUFFEREVENTS
-/* XXXX These generic versions could be simplified by making them
-   type-specific */
-
-/** Callback: Invoked whenever bytes are added to or drained from an input
- * evbuffer.  Used to track the number of bytes read. */
-static void
-evbuffer_inbuf_callback(struct evbuffer *buf,
-                        const struct evbuffer_cb_info *info, void *arg)
-{
-  connection_t *conn = arg;
-  (void) buf;
-  /* XXXX These need to get real counts on the non-nested TLS case. - NM */
-  if (info->n_added) {
-    time_t now = approx_time();
-    conn->timestamp_lastread = now;
-    record_num_bytes_transferred(conn, now, info->n_added, 0);
-    connection_consider_empty_read_buckets(conn);
-    if (conn->type == CONN_TYPE_AP) {
-      edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
-      /*XXXX++ check for overflow*/
-      edge_conn->n_read += (int)info->n_added;
-    }
-  }
-}
-
-/** Callback: Invoked whenever bytes are added to or drained from an output
- * evbuffer.  Used to track the number of bytes written. */
-static void
-evbuffer_outbuf_callback(struct evbuffer *buf,
-                         const struct evbuffer_cb_info *info, void *arg)
-{
-  connection_t *conn = arg;
-  (void)buf;
-  if (info->n_deleted) {
-    time_t now = approx_time();
-    conn->timestamp_lastwritten = now;
-    record_num_bytes_transferred(conn, now, 0, info->n_deleted);
-    connection_consider_empty_write_buckets(conn);
-    if (conn->type == CONN_TYPE_AP) {
-      edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
-      /*XXXX++ check for overflow*/
-      edge_conn->n_written += (int)info->n_deleted;
-    }
-  }
-}
-
-/** Callback: invoked whenever a bufferevent has read data. */
-void
-connection_handle_read_cb(struct bufferevent *bufev, void *arg)
-{
-  connection_t *conn = arg;
-  (void) bufev;
-  if (!conn->marked_for_close) {
-    if (connection_process_inbuf(conn, 1)<0) /* XXXX Always 1? */
-      if (!conn->marked_for_close)
-        connection_mark_for_close(conn);
-  }
-}
-
-/** Callback: invoked whenever a bufferevent has written data. */
-void
-connection_handle_write_cb(struct bufferevent *bufev, void *arg)
-{
-  connection_t *conn = arg;
-  struct evbuffer *output;
-  if (connection_flushed_some(conn)<0) {
-    if (!conn->marked_for_close)
-      connection_mark_for_close(conn);
-    return;
-  }
-
-  output = bufferevent_get_output(bufev);
-  if (!evbuffer_get_length(output)) {
-    connection_finished_flushing(conn);
-    if (conn->marked_for_close && conn->hold_open_until_flushed) {
-      conn->hold_open_until_flushed = 0;
-      if (conn->linked) {
-        /* send eof */
-        bufferevent_flush(conn->bufev, EV_WRITE, BEV_FINISHED);
-      }
-    }
-  }
-}
-
-/** Callback: invoked whenever a bufferevent has had an event (like a
- * connection, or an eof, or an error) occur. */
-void
-connection_handle_event_cb(struct bufferevent *bufev, short event, void *arg)
-{
-  connection_t *conn = arg;
-  (void) bufev;
-  if (conn->marked_for_close)
-    return;
-
-  if (event & BEV_EVENT_CONNECTED) {
-    tor_assert(connection_state_is_connecting(conn));
-    if (connection_finished_connecting(conn)<0)
-      return;
-  }
-  if (event & BEV_EVENT_EOF) {
-    if (!conn->marked_for_close) {
-      conn->inbuf_reached_eof = 1;
-      if (connection_reached_eof(conn)<0)
-        return;
-    }
-  }
-  if (event & BEV_EVENT_ERROR) {
-    int socket_error = evutil_socket_geterror(conn->s);
-    if (conn->type == CONN_TYPE_OR &&
-        conn->state == OR_CONN_STATE_CONNECTING) {
-      connection_or_connect_failed(TO_OR_CONN(conn),
-                                   errno_to_orconn_end_reason(socket_error),
-                                   tor_socket_strerror(socket_error));
-    } else if (CONN_IS_EDGE(conn)) {
-      edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
-      if (!edge_conn->edge_has_sent_end)
-        connection_edge_end_errno(edge_conn);
-      if (conn->type == CONN_TYPE_AP && TO_ENTRY_CONN(conn)->socks_request) {
-        /* broken, don't send a socks reply back */
-        TO_ENTRY_CONN(conn)->socks_request->has_finished = 1;
-      }
-    }
-    connection_close_immediate(conn); /* Connection is dead. */
-    if (!conn->marked_for_close)
-      connection_mark_for_close(conn);
-  }
-}
-
-/** Set up the generic callbacks for the bufferevent on <b>conn</b>. */
-void
-connection_configure_bufferevent_callbacks(connection_t *conn)
-{
-  struct bufferevent *bufev;
-  struct evbuffer *input, *output;
-  tor_assert(conn->bufev);
-  bufev = conn->bufev;
-  bufferevent_setcb(bufev,
-                    connection_handle_read_cb,
-                    connection_handle_write_cb,
-                    connection_handle_event_cb,
-                    conn);
-  /* Set a fairly high write low-watermark so that we get the write callback
-     called whenever data is written to bring us under 128K.  Leave the
-     high-watermark at 0.
-  */
-  bufferevent_setwatermark(bufev, EV_WRITE, 128*1024, 0);
-
-  input = bufferevent_get_input(bufev);
-  output = bufferevent_get_output(bufev);
-  evbuffer_add_cb(input, evbuffer_inbuf_callback, conn);
-  evbuffer_add_cb(output, evbuffer_outbuf_callback, conn);
-}
-#endif
-
 /** A pass-through to fetch_from_buf. */
 int
 connection_fetch_from_buf(char *string, size_t len, connection_t *conn)
@@ -4902,15 +4576,6 @@ assert_connection_ok(connection_t *conn, time_t now)
   tor_assert(conn->type >= CONN_TYPE_MIN_);
   tor_assert(conn->type <= CONN_TYPE_MAX_);
 
-#ifdef USE_BUFFEREVENTS
-  if (conn->bufev) {
-    tor_assert(conn->read_event == NULL);
-    tor_assert(conn->write_event == NULL);
-    tor_assert(conn->inbuf == NULL);
-    tor_assert(conn->outbuf == NULL);
-  }
-#endif
-
   switch (conn->type) {
     case CONN_TYPE_OR:
     case CONN_TYPE_EXT_OR:
@@ -5174,11 +4839,6 @@ connection_free_all(void)
 
   tor_free(last_interface_ipv4);
   tor_free(last_interface_ipv6);
-
-#ifdef USE_BUFFEREVENTS
-  if (global_rate_limit)
-    bufferevent_rate_limit_group_free(global_rate_limit);
-#endif
 }
 
 /** Log a warning, and possibly emit a control event, that <b>received</b> came
diff --git a/src/or/connection.h b/src/or/connection.h
index 4835235fba..7f659dce70 100644
--- a/src/or/connection.h
+++ b/src/or/connection.h
@@ -257,19 +257,7 @@ void clock_skew_warning(const connection_t *conn, long apparent_skew,
                         int trusted, log_domain_mask_t domain,
                         const char *received, const char *source);
 
-#ifdef USE_BUFFEREVENTS
-int connection_type_uses_bufferevent(connection_t *conn);
-void connection_configure_bufferevent_callbacks(connection_t *conn);
-void connection_handle_read_cb(struct bufferevent *bufev, void *arg);
-void connection_handle_write_cb(struct bufferevent *bufev, void *arg);
-void connection_handle_event_cb(struct bufferevent *bufev, short event,
-                                 void *arg);
-void connection_get_rate_limit_totals(uint64_t *read_out,
-                                      uint64_t *written_out);
-void connection_enable_rate_limiting(connection_t *conn);
-#else
 #define connection_type_uses_bufferevent(c) (0)
-#endif
 
 #ifdef CONNECTION_PRIVATE
 STATIC void connection_free_(connection_t *conn);
diff --git a/src/or/connection_or.c b/src/or/connection_or.c
index c69a2ad377..c22e92cd55 100644
--- a/src/or/connection_or.c
+++ b/src/or/connection_or.c
@@ -42,10 +42,6 @@
 #include "ext_orport.h"
 #include "scheduler.h"
 
-#ifdef USE_BUFFEREVENTS
-#include <event2/bufferevent_ssl.h>
-#endif
-
 static int connection_tls_finish_handshake(or_connection_t *conn);
 static int connection_or_launch_v3_or_handshake(or_connection_t *conn);
 static int connection_or_process_cells_from_inbuf(or_connection_t *conn);
@@ -66,12 +62,6 @@ static void connection_or_mark_bad_for_new_circs(or_connection_t *or_conn);
 
 static void connection_or_change_state(or_connection_t *conn, uint8_t state);
 
-#ifdef USE_BUFFEREVENTS
-static void connection_or_handle_event_cb(struct bufferevent *bufev,
-                                          short event, void *arg);
-#include <event2/buffer.h>/*XXXX REMOVE */
-#endif
-
 /**************************************************************/
 
 /** Map from identity digest of connected OR or desired OR to a connection_t
@@ -565,13 +555,6 @@ connection_or_process_inbuf(or_connection_t *conn)
 
       return ret;
     case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING:
-#ifdef USE_BUFFEREVENTS
-      if (tor_tls_server_got_renegotiate(conn->tls))
-        connection_or_tls_renegotiated_cb(conn->tls, conn);
-      if (conn->base_.marked_for_close)
-        return 0;
-      /* fall through. */
-#endif
     case OR_CONN_STATE_OPEN:
     case OR_CONN_STATE_OR_HANDSHAKING_V2:
     case OR_CONN_STATE_OR_HANDSHAKING_V3:
@@ -807,27 +790,6 @@ connection_or_update_token_buckets_helper(or_connection_t *conn, int reset,
 
   conn->bandwidthrate = rate;
   conn->bandwidthburst = burst;
-#ifdef USE_BUFFEREVENTS
-  {
-    const struct timeval *tick = tor_libevent_get_one_tick_timeout();
-    struct ev_token_bucket_cfg *cfg, *old_cfg;
-    int64_t rate64 = (((int64_t)rate) * options->TokenBucketRefillInterval)
-      / 1000;
-    /* This can't overflow, since TokenBucketRefillInterval <= 1000,
-     * and rate started out less than INT_MAX. */
-    int rate_per_tick = (int) rate64;
-
-    cfg = ev_token_bucket_cfg_new(rate_per_tick, burst, rate_per_tick,
-                                  burst, tick);
-    old_cfg = conn->bucket_cfg;
-    if (conn->base_.bufev)
-      tor_set_bufferevent_rate_limit(conn->base_.bufev, cfg);
-    if (old_cfg)
-      ev_token_bucket_cfg_free(old_cfg);
-    conn->bucket_cfg = cfg;
-    (void) reset; /* No way to do this with libevent yet. */
-  }
-#else
   if (reset) { /* set up the token buckets to be full */
     conn->read_bucket = conn->write_bucket = burst;
     return;
@@ -838,7 +800,6 @@ connection_or_update_token_buckets_helper(or_connection_t *conn, int reset,
     conn->read_bucket = burst;
   if (conn->write_bucket > burst)
     conn->write_bucket = burst;
-#endif
 }
 
 /** Either our set of relays or our per-conn rate limits have changed.
@@ -1395,29 +1356,6 @@ connection_tls_start_handshake,(or_connection_t *conn, int receiving))
   tor_tls_set_logged_address(conn->tls, // XXX client and relay?
       escaped_safe_str(conn->base_.address));
 
-#ifdef USE_BUFFEREVENTS
-  if (connection_type_uses_bufferevent(TO_CONN(conn))) {
-    const int filtering = get_options()->UseFilteringSSLBufferevents;
-    struct bufferevent *b =
-      tor_tls_init_bufferevent(conn->tls, conn->base_.bufev, conn->base_.s,
-                               receiving, filtering);
-    if (!b) {
-      log_warn(LD_BUG,"tor_tls_init_bufferevent failed. Closing.");
-      return -1;
-    }
-    conn->base_.bufev = b;
-    if (conn->bucket_cfg)
-      tor_set_bufferevent_rate_limit(conn->base_.bufev, conn->bucket_cfg);
-    connection_enable_rate_limiting(TO_CONN(conn));
-
-    connection_configure_bufferevent_callbacks(TO_CONN(conn));
-    bufferevent_setcb(b,
-                      connection_handle_read_cb,
-                      connection_handle_write_cb,
-                      connection_or_handle_event_cb,/* overriding this one*/
-                      TO_CONN(conn));
-  }
-#endif
   connection_start_reading(TO_CONN(conn));
   log_debug(LD_HANDSHAKE,"starting TLS handshake on fd "TOR_SOCKET_T_FORMAT,
             conn->base_.s);
@@ -1517,75 +1455,6 @@ connection_tls_continue_handshake(or_connection_t *conn)
   return 0;
 }
 
-#ifdef USE_BUFFEREVENTS
-static void
-connection_or_handle_event_cb(struct bufferevent *bufev, short event,
-                              void *arg)
-{
-  struct or_connection_t *conn = TO_OR_CONN(arg);
-
-  /* XXXX cut-and-paste code; should become a function. */
-  if (event & BEV_EVENT_CONNECTED) {
-    if (conn->base_.state == OR_CONN_STATE_TLS_HANDSHAKING) {
-      if (tor_tls_finish_handshake(conn->tls) < 0) {
-        log_warn(LD_OR, "Problem finishing handshake");
-        connection_or_close_for_error(conn, 0);
-        return;
-      }
-    }
-
-    if (! tor_tls_used_v1_handshake(conn->tls)) {
-      if (!tor_tls_is_server(conn->tls)) {
-        if (conn->base_.state == OR_CONN_STATE_TLS_HANDSHAKING) {
-          if (connection_or_launch_v3_or_handshake(conn) < 0)
-            connection_or_close_for_error(conn, 0);
-        }
-      } else {
-        const int handshakes = tor_tls_get_num_server_handshakes(conn->tls);
-
-        if (handshakes == 1) {
-          /* v2 or v3 handshake, as a server. Only got one handshake, so
-           * wait for the next one. */
-          tor_tls_set_renegotiate_callback(conn->tls,
-                                           connection_or_tls_renegotiated_cb,
-                                           conn);
-          connection_or_change_state(conn,
-              OR_CONN_STATE_TLS_SERVER_RENEGOTIATING);
-        } else if (handshakes == 2) {
-          /* v2 handshake, as a server.  Two handshakes happened already,
-           * so we treat renegotiation as done.
-           */
-          connection_or_tls_renegotiated_cb(conn->tls, conn);
-        } else if (handshakes > 2) {
-          log_warn(LD_OR, "More than two handshakes done on connection. "
-                   "Closing.");
-          connection_or_close_for_error(conn, 0);
-        } else {
-          log_warn(LD_BUG, "We were unexpectedly told that a connection "
-                   "got %d handshakes. Closing.", handshakes);
-          connection_or_close_for_error(conn, 0);
-        }
-        return;
-      }
-    }
-    connection_watch_events(TO_CONN(conn), READ_EVENT|WRITE_EVENT);
-    if (connection_tls_finish_handshake(conn) < 0)
-      connection_or_close_for_error(conn, 0); /* ???? */
-    return;
-  }
-
-  if (event & BEV_EVENT_ERROR) {
-    unsigned long err;
-    while ((err = bufferevent_get_openssl_error(bufev))) {
-      tor_tls_log_one_error(conn->tls, err, LOG_WARN, LD_OR,
-                            "handshaking (with bufferevent)");
-    }
-  }
-
-  connection_handle_event_cb(bufev, event, arg);
-}
-#endif
-
 /** Return 1 if we initiated this connection, or 0 if it started
  * out as an incoming connection.
  */
diff --git a/src/or/directory.c b/src/or/directory.c
index 7c1b9884c0..11594ff476 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -3641,16 +3641,8 @@ connection_dir_finished_flushing(dir_connection_t *conn)
       return 0;
     case DIR_CONN_STATE_SERVER_WRITING:
       if (conn->dir_spool_src != DIR_SPOOL_NONE) {
-#ifdef USE_BUFFEREVENTS
-        /* This can happen with paired bufferevents, since a paired connection
-         * can flush immediately when you write to it, making the subsequent
-         * check in connection_handle_write_cb() decide that the connection
-         * is flushed. */
-        log_debug(LD_DIRSERV, "Emptied a dirserv buffer, but still spooling.");
-#else
         log_warn(LD_BUG, "Emptied a dirserv buffer, but it's still spooling!");
         connection_mark_for_close(TO_CONN(conn));
-#endif
       } else {
         log_debug(LD_DIRSERV, "Finished writing server response. Closing.");
         connection_mark_for_close(TO_CONN(conn));
diff --git a/src/or/main.c b/src/or/main.c
index 404d741c38..07c61b8506 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -71,10 +71,6 @@
 
 #include <event2/event.h>
 
-#ifdef USE_BUFFEREVENTS
-#include <event2/bufferevent.h>
-#endif
-
 #ifdef HAVE_SYSTEMD
 #   if defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__)
 /* Systemd's use of gcc's __INCLUDE_LEVEL__ extension macro appears to confuse
@@ -101,8 +97,6 @@ static int run_main_loop_until_done(void);
 static void process_signal(int sig);
 
 /********* START VARIABLES **********/
-
-#ifndef USE_BUFFEREVENTS
 int global_read_bucket; /**< Max number of bytes I can read this second. */
 int global_write_bucket; /**< Max number of bytes I can write this second. */
 
@@ -116,7 +110,6 @@ static int stats_prev_global_read_bucket;
 /** What was the write bucket before the last second_elapsed_callback() call?
  * (used to determine how many bytes we've written). */
 static int stats_prev_global_write_bucket;
-#endif
 
 /* DOCDOC stats_prev_n_read */
 static uint64_t stats_prev_n_read = 0;
@@ -188,28 +181,6 @@ int quiet_level = 0;
  *
  ****************************************************************************/
 
-#if defined(_WIN32) && defined(USE_BUFFEREVENTS)
-/** Remove the kernel-space send and receive buffers for <b>s</b>. For use
- * with IOCP only. */
-static int
-set_buffer_lengths_to_zero(tor_socket_t s)
-{
-  int zero = 0;
-  int r = 0;
-  if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (void*)&zero,
-                 (socklen_t)sizeof(zero))) {
-    log_warn(LD_NET, "Unable to clear SO_SNDBUF");
-    r = -1;
-  }
-  if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, (void*)&zero,
-                 (socklen_t)sizeof(zero))) {
-    log_warn(LD_NET, "Unable to clear SO_RCVBUF");
-    r = -1;
-  }
-  return r;
-}
-#endif
-
 /** Return 1 if we have successfully built a circuit, and nothing has changed
  * to make us think that maybe we can't.
  */
@@ -252,64 +223,7 @@ connection_add_impl(connection_t *conn, int is_connecting)
   conn->conn_array_index = smartlist_len(connection_array);
   smartlist_add(connection_array, conn);
 
-#ifdef USE_BUFFEREVENTS
-  if (connection_type_uses_bufferevent(conn)) {
-    if (SOCKET_OK(conn->s) && !conn->linked) {
-
-#ifdef _WIN32
-      if (tor_libevent_using_iocp_bufferevents() &&
-          get_options()->UserspaceIOCPBuffers) {
-        set_buffer_lengths_to_zero(conn->s);
-      }
-#endif
-
-      conn->bufev = bufferevent_socket_new(
-                         tor_libevent_get_base(),
-                         conn->s,
-                         BEV_OPT_DEFER_CALLBACKS);
-      if (!conn->bufev) {
-        log_warn(LD_BUG, "Unable to create socket bufferevent");
-        smartlist_del(connection_array, conn->conn_array_index);
-        conn->conn_array_index = -1;
-        return -1;
-      }
-      if (is_connecting) {
-        /* Put the bufferevent into a "connecting" state so that we'll get
-         * a "connected" event callback on successful write. */
-        bufferevent_socket_connect(conn->bufev, NULL, 0);
-      }
-      connection_configure_bufferevent_callbacks(conn);
-    } else if (conn->linked && conn->linked_conn &&
-               connection_type_uses_bufferevent(conn->linked_conn)) {
-      tor_assert(!(SOCKET_OK(conn->s)));
-      if (!conn->bufev) {
-        struct bufferevent *pair[2] = { NULL, NULL };
-        if (bufferevent_pair_new(tor_libevent_get_base(),
-                                 BEV_OPT_DEFER_CALLBACKS,
-                                 pair) < 0) {
-          log_warn(LD_BUG, "Unable to create bufferevent pair");
-          smartlist_del(connection_array, conn->conn_array_index);
-          conn->conn_array_index = -1;
-          return -1;
-        }
-        tor_assert(pair[0]);
-        conn->bufev = pair[0];
-        conn->linked_conn->bufev = pair[1];
-      } /* else the other side already was added, and got a bufferevent_pair */
-      connection_configure_bufferevent_callbacks(conn);
-    } else {
-      tor_assert(!conn->linked);
-    }
-
-    if (conn->bufev)
-      tor_assert(conn->inbuf == NULL);
-
-    if (conn->linked_conn && conn->linked_conn->bufev)
-      tor_assert(conn->linked_conn->inbuf == NULL);
-  }
-#else
   (void) is_connecting;
-#endif
 
   if (!HAS_BUFFEREVENT(conn) && (SOCKET_OK(conn->s) || conn->linked)) {
     conn->read_event = tor_event_new(tor_libevent_get_base(),
@@ -340,12 +254,6 @@ connection_unregister_events(connection_t *conn)
       log_warn(LD_BUG, "Error removing write event for %d", (int)conn->s);
     tor_free(conn->write_event);
   }
-#ifdef USE_BUFFEREVENTS
-  if (conn->bufev) {
-    bufferevent_free(conn->bufev);
-    conn->bufev = NULL;
-  }
-#endif
   if (conn->type == CONN_TYPE_AP_DNS_LISTENER) {
     dnsserv_close_listener(conn);
   }
@@ -876,21 +784,6 @@ conn_close_if_marked(int i)
   assert_connection_ok(conn, now);
   /* assert_all_pending_dns_resolves_ok(); */
 
-#ifdef USE_BUFFEREVENTS
-  if (conn->bufev) {
-    if (conn->hold_open_until_flushed &&
-        evbuffer_get_length(bufferevent_get_output(conn->bufev))) {
-      /* don't close yet. */
-      return 0;
-    }
-    if (conn->linked_conn && ! conn->linked_conn->marked_for_close) {
-      /* We need to do this explicitly so that the linked connection
-       * notices that there was an EOF. */
-      bufferevent_flush(conn->bufev, EV_WRITE, BEV_FINISHED);
-    }
-  }
-#endif
-
   log_debug(LD_NET,"Cleaning up connection (fd "TOR_SOCKET_T_FORMAT").",
             conn->s);
 
@@ -985,9 +878,6 @@ conn_close_if_marked(int i)
     }
   }
 
-#ifdef USE_BUFFEREVENTS
- unlink:
-#endif
   connection_unlink(conn); /* unlink, remove, free */
   return 1;
 }
@@ -1133,11 +1023,7 @@ run_connection_housekeeping(int i, time_t now)
      the connection or send a keepalive, depending. */
 
   or_conn = TO_OR_CONN(conn);
-#ifdef USE_BUFFEREVENTS
-  tor_assert(conn->bufev);
-#else
   tor_assert(conn->outbuf);
-#endif
 
   chan = TLS_CHAN_TO_BASE(or_conn->chan);
   tor_assert(chan);
@@ -2051,25 +1937,10 @@ second_elapsed_callback(periodic_timer_t *timer, void *arg)
 
   /* the second has rolled over. check more stuff. */
   seconds_elapsed = current_second ? (int)(now - current_second) : 0;
-#ifdef USE_BUFFEREVENTS
-  {
-    uint64_t cur_read,cur_written;
-    connection_get_rate_limit_totals(&cur_read, &cur_written);
-    bytes_written = (size_t)(cur_written - stats_prev_n_written);
-    bytes_read = (size_t)(cur_read - stats_prev_n_read);
-    stats_n_bytes_read += bytes_read;
-    stats_n_bytes_written += bytes_written;
-    if (accounting_is_enabled(options) && seconds_elapsed >= 0)
-      accounting_add_bytes(bytes_read, bytes_written, seconds_elapsed);
-    stats_prev_n_written = cur_written;
-    stats_prev_n_read = cur_read;
-  }
-#else
   bytes_read = (size_t)(stats_n_bytes_read - stats_prev_n_read);
   bytes_written = (size_t)(stats_n_bytes_written - stats_prev_n_written);
   stats_prev_n_read = stats_n_bytes_read;
   stats_prev_n_written = stats_n_bytes_written;
-#endif
 
   control_event_bandwidth_used((uint32_t)bytes_read,(uint32_t)bytes_written);
   control_event_stream_bandwidth_used();
@@ -2141,7 +2012,6 @@ systemd_watchdog_callback(periodic_timer_t *timer, void *arg)
 }
 #endif
 
-#ifndef USE_BUFFEREVENTS
 /** Timer: used to invoke refill_callback(). */
 static periodic_timer_t *refill_timer = NULL;
 
@@ -2190,7 +2060,6 @@ refill_callback(periodic_timer_t *timer, void *arg)
 
   current_millisecond = now; /* remember what time it is, for next time */
 }
-#endif
 
 #ifndef _WIN32
 /** Called when a possibly ignorable libevent error occurs; ensures that we
@@ -2366,13 +2235,6 @@ do_main_loop(void)
     }
   }
 
-#ifdef USE_BUFFEREVENTS
-  log_warn(LD_GENERAL, "Tor was compiled with the --enable-bufferevents "
-           "option. This is still experimental, and might cause strange "
-           "bugs. If you want a more stable Tor, be sure to build without "
-           "--enable-bufferevents.");
-#endif
-
   handle_signals(1);
 
   /* load the private keys, if we're supposed to have them, and set up the
@@ -2386,10 +2248,8 @@ do_main_loop(void)
 
   /* Set up our buckets */
   connection_bucket_init();
-#ifndef USE_BUFFEREVENTS
   stats_prev_global_read_bucket = global_read_bucket;
   stats_prev_global_write_bucket = global_write_bucket;
-#endif
 
   /* initialize the bootstrap status events to know we're starting up */
   control_event_bootstrap(BOOTSTRAP_STATUS_STARTING, 0);
@@ -2486,7 +2346,6 @@ do_main_loop(void)
   }
 #endif
 
-#ifndef USE_BUFFEREVENTS
   if (!refill_timer) {
     struct timeval refill_interval;
     int msecs = get_options()->TokenBucketRefillInterval;
@@ -2500,7 +2359,6 @@ do_main_loop(void)
                                       NULL);
     tor_assert(refill_timer);
   }
-#endif
 
 #ifdef HAVE_SYSTEMD
   {
@@ -2994,12 +2852,8 @@ tor_init(int argc, char *argv[])
 
   {
     const char *version = get_version();
-    const char *bev_str =
-#ifdef USE_BUFFEREVENTS
-      "(with bufferevents) ";
-#else
-      "";
-#endif
+    const char *bev_str = "";
+
     log_notice(LD_GENERAL, "Tor v%s %srunning on %s with Libevent %s, "
                "OpenSSL %s and Zlib %s.", version, bev_str,
                get_uname(),
@@ -3177,9 +3031,7 @@ tor_free_all(int postfork)
   smartlist_free(active_linked_connection_lst);
   periodic_timer_free(second_timer);
   teardown_periodic_events();
-#ifndef USE_BUFFEREVENTS
   periodic_timer_free(refill_timer);
-#endif
 
   if (!postfork) {
     release_lockfile();
diff --git a/src/or/or.h b/src/or/or.h
index af40cf7e81..d04fc28564 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -66,12 +66,6 @@
 #include <windows.h>
 #endif
 
-#ifdef USE_BUFFEREVENTS
-#include <event2/bufferevent.h>
-#include <event2/buffer.h>
-#include <event2/util.h>
-#endif
-
 #include "crypto.h"
 #include "crypto_format.h"
 #include "tortls.h"
@@ -1137,11 +1131,8 @@ typedef struct {
 
 typedef struct buf_t buf_t;
 typedef struct socks_request_t socks_request_t;
-#ifdef USE_BUFFEREVENTS
-#define generic_buffer_t struct evbuffer
-#else
+
 #define generic_buffer_t buf_t
-#endif
 
 typedef struct entry_port_cfg_t {
   /* Client port types (socks, dns, trans, natd) only: */
@@ -1280,10 +1271,6 @@ typedef struct connection_t {
   time_t timestamp_lastwritten; /**< When was the last time libevent said we
                                  * could write? */
 
-#ifdef USE_BUFFEREVENTS
-  struct bufferevent *bufev; /**< A Libevent buffered IO structure. */
-#endif
-
   time_t timestamp_created; /**< When was this connection_t created? */
 
   int socket_family; /**< Address family of this connection's socket.  Usually
@@ -1523,17 +1510,10 @@ typedef struct or_connection_t {
   /* bandwidth* and *_bucket only used by ORs in OPEN state: */
   int bandwidthrate; /**< Bytes/s added to the bucket. (OPEN ORs only.) */
   int bandwidthburst; /**< Max bucket size for this conn. (OPEN ORs only.) */
-#ifndef USE_BUFFEREVENTS
   int read_bucket; /**< When this hits 0, stop receiving. Every second we
                     * add 'bandwidthrate' to this, capping it at
                     * bandwidthburst. (OPEN ORs only) */
   int write_bucket; /**< When this hits 0, stop writing. Like read_bucket. */
-#else
-  /** A rate-limiting configuration object to determine how this connection
-   * set its read- and write- limits. */
-  /* XXXX we could share this among all connections. */
-  struct ev_token_bucket_cfg *bucket_cfg;
-#endif
 
   struct or_connection_t *next_with_same_id; /**< Next connection with same
                                               * identity digest as this one. */
@@ -1874,22 +1854,11 @@ static inline listener_connection_t *TO_LISTENER_CONN(connection_t *c)
    and if we aren't using bufferevents, they expand more or less to:
       { do non-bufferevent stuff; }
 */
-#ifdef USE_BUFFEREVENTS
-#define HAS_BUFFEREVENT(c) (((c)->bufev) != NULL)
-#define IF_HAS_BUFFEREVENT(c, stmt)                \
-  if ((c)->bufev) do {                             \
-      stmt ;                                       \
-  } while (0)
-#define ELSE_IF_NO_BUFFEREVENT ; else
-#define IF_HAS_NO_BUFFEREVENT(c)                   \
-  if (NULL == (c)->bufev)
-#else
 #define HAS_BUFFEREVENT(c) (0)
 #define IF_HAS_BUFFEREVENT(c, stmt) (void)0
 #define ELSE_IF_NO_BUFFEREVENT ;
 #define IF_HAS_NO_BUFFEREVENT(c)                \
   if (1)
-#endif
 
 /** What action type does an address policy indicate: accept or reject? */
 typedef enum {