diff --git a/.travis.yml b/.travis.yml
index ff8d82049..bceca5404 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -71,7 +71,7 @@ install:
   - git clone https://github.com/openresty/set-misc-nginx-module.git ../set-misc-nginx-module
   - git clone https://github.com/openresty/mockeagain.git
   - git clone https://github.com/openresty/test-nginx.git
-  - git clone https://github.com/openresty/stream-lua-nginx-module.git ../stream-lua-nginx-module
+  - git clone -b port-ngx-lua-v0.10.15-changes https://github.com/thibaultcha/stream-lua-nginx-module.git ../stream-lua-nginx-module
 
 script:
   - cd luajit2/
diff --git a/lib/resty/core.lua b/lib/resty/core.lua
index 57c9d175d..449f847b0 100644
--- a/lib/resty/core.lua
+++ b/lib/resty/core.lua
@@ -3,22 +3,22 @@
 local subsystem = ngx.config.subsystem
 
 
+require "resty.core.ctx"
+require "resty.core.var"
+require "resty.core.worker"
 require "resty.core.regex"
 require "resty.core.shdict"
 require "resty.core.time"
 require "resty.core.misc"
+require "resty.core.hash"
+require "resty.core.uri"
+require "resty.core.exit"
+require "resty.core.base64"
 
 
 if subsystem == 'http' then
-    require "resty.core.uri"
-    require "resty.core.hash"
-    require "resty.core.base64"
-    require "resty.core.exit"
-    require "resty.core.var"
-    require "resty.core.ctx"
     require "resty.core.request"
     require "resty.core.response"
-    require "resty.core.worker"
     require "resty.core.phase"
     require "resty.core.ndk"
 end
diff --git a/lib/resty/core/base64.lua b/lib/resty/core/base64.lua
index 981424cc7..8a0e463b4 100644
--- a/lib/resty/core/base64.lua
+++ b/lib/resty/core/base64.lua
@@ -1,21 +1,28 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
+local ffi = require "ffi"
 local base = require "resty.core.base"
 
-local ffi_string = ffi.string
+
 local C = ffi.C
+local ffi_string = ffi.string
 local ngx = ngx
 local type = type
-local tostring = tostring
 local error = error
+local floor = math.floor
+local tostring = tostring
 local get_string_buf = base.get_string_buf
 local get_size_ptr = base.get_size_ptr
-local floor = math.floor
+local subsystem = ngx.config.subsystem
 
 
-ffi.cdef[[
+local ngx_lua_ffi_encode_base64
+local ngx_lua_ffi_decode_base64
+
+
+if subsystem == "http" then
+    ffi.cdef[[
     size_t ngx_http_lua_ffi_encode_base64(const unsigned char *src,
                                           size_t len, unsigned char *dst,
                                           int no_padding);
@@ -23,7 +30,25 @@ ffi.cdef[[
     int ngx_http_lua_ffi_decode_base64(const unsigned char *src,
                                        size_t len, unsigned char *dst,
                                        size_t *dlen);
-]]
+    ]]
+
+    ngx_lua_ffi_encode_base64 = C.ngx_http_lua_ffi_encode_base64
+    ngx_lua_ffi_decode_base64 = C.ngx_http_lua_ffi_decode_base64
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    size_t ngx_stream_lua_ffi_encode_base64(const unsigned char *src,
+                                            size_t len, unsigned char *dst,
+                                            int no_padding);
+
+    int ngx_stream_lua_ffi_decode_base64(const unsigned char *src,
+                                         size_t len, unsigned char *dst,
+                                         size_t *dlen);
+    ]]
+
+    ngx_lua_ffi_encode_base64 = C.ngx_stream_lua_ffi_encode_base64
+    ngx_lua_ffi_decode_base64 = C.ngx_stream_lua_ffi_decode_base64
+end
 
 
 local function base64_encoded_length(len, no_padding)
@@ -57,8 +82,7 @@ ngx.encode_base64 = function (s, no_padding)
 
     local dlen = base64_encoded_length(slen, no_padding_bool)
     local dst = get_string_buf(dlen)
-    local r_dlen = C.ngx_http_lua_ffi_encode_base64(s, slen, dst,
-                                                    no_padding_int)
+    local r_dlen = ngx_lua_ffi_encode_base64(s, slen, dst, no_padding_int)
     -- if dlen ~= r_dlen then error("discrepancy in len") end
     return ffi_string(dst, r_dlen)
 end
@@ -78,7 +102,7 @@ ngx.decode_base64 = function (s)
     -- print("dlen: ", tonumber(dlen))
     local dst = get_string_buf(dlen)
     local pdlen = get_size_ptr()
-    local ok = C.ngx_http_lua_ffi_decode_base64(s, slen, dst, pdlen)
+    local ok = ngx_lua_ffi_decode_base64(s, slen, dst, pdlen)
     if ok == 0 then
         return nil
     end
diff --git a/lib/resty/core/ctx.lua b/lib/resty/core/ctx.lua
index e348a7eb4..0683aaaf9 100644
--- a/lib/resty/core/ctx.lua
+++ b/lib/resty/core/ctx.lua
@@ -1,28 +1,47 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
-local debug = require 'debug'
+local ffi = require "ffi"
+local debug = require "debug"
 local base = require "resty.core.base"
 local misc = require "resty.core.misc"
 
 
+local C = ffi.C
 local register_getter = misc.register_ngx_magic_key_getter
 local register_setter = misc.register_ngx_magic_key_setter
 local registry = debug.getregistry()
 local new_tab = base.new_tab
 local ref_in_table = base.ref_in_table
 local get_request = base.get_request
-local C = ffi.C
 local FFI_NO_REQ_CTX = base.FFI_NO_REQ_CTX
 local FFI_OK = base.FFI_OK
 local error = error
+local subsystem = ngx.config.subsystem
+
+
+local ngx_lua_ffi_get_ctx_ref
+local ngx_lua_ffi_set_ctx_ref
 
 
-ffi.cdef[[
-int ngx_http_lua_ffi_get_ctx_ref(ngx_http_request_t *r);
-int ngx_http_lua_ffi_set_ctx_ref(ngx_http_request_t *r, int ref);
-]]
+if subsystem == "http" then
+    ffi.cdef[[
+    int ngx_http_lua_ffi_get_ctx_ref(ngx_http_request_t *r);
+    int ngx_http_lua_ffi_set_ctx_ref(ngx_http_request_t *r, int ref);
+    ]]
+
+    ngx_lua_ffi_get_ctx_ref = C.ngx_http_lua_ffi_get_ctx_ref
+    ngx_lua_ffi_set_ctx_ref = C.ngx_http_lua_ffi_set_ctx_ref
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    int ngx_stream_lua_ffi_get_ctx_ref(ngx_stream_lua_request_t *r);
+    int ngx_stream_lua_ffi_set_ctx_ref(ngx_stream_lua_request_t *r, int ref);
+    ]]
+
+    ngx_lua_ffi_get_ctx_ref = C.ngx_stream_lua_ffi_get_ctx_ref
+    ngx_lua_ffi_set_ctx_ref = C.ngx_stream_lua_ffi_set_ctx_ref
+end
 
 
 local _M = {
@@ -37,7 +56,7 @@ local function get_ctx_table()
         error("no request found")
     end
 
-    local ctx_ref = C.ngx_http_lua_ffi_get_ctx_ref(r)
+    local ctx_ref = ngx_lua_ffi_get_ctx_ref(r)
     if ctx_ref == FFI_NO_REQ_CTX then
         error("no request ctx found")
     end
@@ -46,7 +65,7 @@ local function get_ctx_table()
     if ctx_ref < 0 then
         local ctx = new_tab(0, 4)
         ctx_ref = ref_in_table(ctxs, ctx)
-        if C.ngx_http_lua_ffi_set_ctx_ref(r, ctx_ref) ~= FFI_OK then
+        if ngx_lua_ffi_set_ctx_ref(r, ctx_ref) ~= FFI_OK then
             return nil
         end
         return ctx
@@ -63,7 +82,7 @@ local function set_ctx_table(ctx)
         error("no request found")
     end
 
-    local ctx_ref = C.ngx_http_lua_ffi_get_ctx_ref(r)
+    local ctx_ref = ngx_lua_ffi_get_ctx_ref(r)
     if ctx_ref == FFI_NO_REQ_CTX then
         error("no request ctx found")
     end
@@ -71,7 +90,7 @@ local function set_ctx_table(ctx)
     local ctxs = registry.ngx_lua_ctx_tables
     if ctx_ref < 0 then
         ctx_ref = ref_in_table(ctxs, ctx)
-        C.ngx_http_lua_ffi_set_ctx_ref(r, ctx_ref)
+        ngx_lua_ffi_set_ctx_ref(r, ctx_ref)
         return
     end
     ctxs[ctx_ref] = ctx
diff --git a/lib/resty/core/exit.lua b/lib/resty/core/exit.lua
index f9f00f791..30a7b613c 100644
--- a/lib/resty/core/exit.lua
+++ b/lib/resty/core/exit.lua
@@ -1,22 +1,40 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
-local ffi_string = ffi.string
+local ffi = require "ffi"
+local base = require "resty.core.base"
+
+
 local C = ffi.C
+local ffi_string = ffi.string
 local ngx = ngx
 local error = error
-local base = require "resty.core.base"
 local get_string_buf = base.get_string_buf
 local get_size_ptr = base.get_size_ptr
 local get_request = base.get_request
 local co_yield = coroutine._yield
+local subsystem = ngx.config.subsystem
 
 
-ffi.cdef[[
+local ngx_lua_ffi_exit
+
+
+if subsystem == "http" then
+    ffi.cdef[[
     int ngx_http_lua_ffi_exit(ngx_http_request_t *r, int status,
                                unsigned char *err, size_t *errlen);
-]]
+    ]]
+
+    ngx_lua_ffi_exit = C.ngx_http_lua_ffi_exit
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    int ngx_stream_lua_ffi_exit(ngx_stream_lua_request_t *r, int status,
+                                unsigned char *err, size_t *errlen);
+    ]]
+
+    ngx_lua_ffi_exit = C.ngx_stream_lua_ffi_exit
+end
 
 
 local ERR_BUF_SIZE = 128
@@ -31,7 +49,7 @@ ngx.exit = function (rc)
         error("no request found")
     end
     errlen[0] = ERR_BUF_SIZE
-    rc = C.ngx_http_lua_ffi_exit(r, rc, err, errlen)
+    rc = ngx_lua_ffi_exit(r, rc, err, errlen)
     if rc == 0 then
         -- print("yielding...")
         return co_yield()
diff --git a/lib/resty/core/hash.lua b/lib/resty/core/hash.lua
index de97270c3..4a09b009d 100644
--- a/lib/resty/core/hash.lua
+++ b/lib/resty/core/hash.lua
@@ -1,18 +1,27 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
-local ffi_string = ffi.string
-local ffi_new = ffi.new
+local ffi = require "ffi"
+local base = require "resty.core.base"
+
+
 local C = ffi.C
+local ffi_new = ffi.new
+local ffi_string = ffi.string
 local ngx = ngx
 local type = type
-local tostring = tostring
 local error = error
-local base = require "resty.core.base"
+local tostring = tostring
+local subsystem = ngx.config.subsystem
+
+
+local ngx_lua_ffi_md5
+local ngx_lua_ffi_md5_bin
+local ngx_lua_ffi_sha1_bin
 
 
-ffi.cdef[[
+if subsystem == "http" then
+    ffi.cdef[[
     void ngx_http_lua_ffi_md5_bin(const unsigned char *src, size_t len,
                                   unsigned char *dst);
 
@@ -21,7 +30,28 @@ ffi.cdef[[
 
     int ngx_http_lua_ffi_sha1_bin(const unsigned char *src, size_t len,
                                   unsigned char *dst);
-]]
+    ]]
+
+    ngx_lua_ffi_md5 = C.ngx_http_lua_ffi_md5
+    ngx_lua_ffi_md5_bin = C.ngx_http_lua_ffi_md5_bin
+    ngx_lua_ffi_sha1_bin = C.ngx_http_lua_ffi_sha1_bin
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    void ngx_stream_lua_ffi_md5_bin(const unsigned char *src, size_t len,
+                                    unsigned char *dst);
+
+    void ngx_stream_lua_ffi_md5(const unsigned char *src, size_t len,
+                                unsigned char *dst);
+
+    int ngx_stream_lua_ffi_sha1_bin(const unsigned char *src, size_t len,
+                                    unsigned char *dst);
+    ]]
+
+    ngx_lua_ffi_md5 = C.ngx_stream_lua_ffi_md5
+    ngx_lua_ffi_md5_bin = C.ngx_stream_lua_ffi_md5_bin
+    ngx_lua_ffi_sha1_bin = C.ngx_stream_lua_ffi_sha1_bin
+end
 
 
 local MD5_DIGEST_LEN = 16
@@ -35,7 +65,7 @@ ngx.md5_bin = function (s)
             s = tostring(s)
         end
     end
-    C.ngx_http_lua_ffi_md5_bin(s, #s, md5_buf)
+    ngx_lua_ffi_md5_bin(s, #s, md5_buf)
     return ffi_string(md5_buf, MD5_DIGEST_LEN)
 end
 
@@ -51,7 +81,7 @@ ngx.md5 = function (s)
             s = tostring(s)
         end
     end
-    C.ngx_http_lua_ffi_md5(s, #s, md5_hex_buf)
+    ngx_lua_ffi_md5(s, #s, md5_hex_buf)
     return ffi_string(md5_hex_buf, MD5_HEX_DIGEST_LEN)
 end
 
@@ -67,7 +97,7 @@ ngx.sha1_bin = function (s)
             s = tostring(s)
         end
     end
-    local ok = C.ngx_http_lua_ffi_sha1_bin(s, #s, sha_buf)
+    local ok = ngx_lua_ffi_sha1_bin(s, #s, sha_buf)
     if ok == 0 then
         error("SHA-1 support missing in Nginx")
     end
diff --git a/lib/resty/core/misc.lua b/lib/resty/core/misc.lua
index 8caab2633..ff7954a2b 100644
--- a/lib/resty/core/misc.lua
+++ b/lib/resty/core/misc.lua
@@ -6,107 +6,98 @@ local ffi = require "ffi"
 local os = require "os"
 
 
-local FFI_OK = base.FFI_OK
-local FFI_NO_REQ_CTX = base.FFI_NO_REQ_CTX
-local FFI_BAD_CONTEXT = base.FFI_BAD_CONTEXT
-local get_string_buf = base.get_string_buf
-local get_string_buf_size = base.get_string_buf_size
-local get_size_ptr = base.get_size_ptr
-local new_tab = base.new_tab
 local C = ffi.C
 local ffi_new = ffi.new
 local ffi_str = ffi.string
-local setmetatable = setmetatable
-local rawget = rawget
-local rawset = rawset
 local ngx = ngx
-local get_request = base.get_request
 local type = type
 local error = error
+local rawget = rawget
+local rawset = rawset
 local tonumber = tonumber
+local setmetatable = setmetatable
+local FFI_OK = base.FFI_OK
+local FFI_NO_REQ_CTX = base.FFI_NO_REQ_CTX
+local FFI_BAD_CONTEXT = base.FFI_BAD_CONTEXT
+local new_tab = base.new_tab
+local get_request = base.get_request
+local get_size_ptr = base.get_size_ptr
+local get_string_buf = base.get_string_buf
+local get_string_buf_size = base.get_string_buf_size
 local subsystem = ngx.config.subsystem
 
 
-local _M
+local ngx_lua_ffi_get_resp_status
 local ngx_lua_ffi_get_conf_env
+local ngx_magic_key_getters
+local ngx_magic_key_setters
 
 
-if subsystem == 'http' then
-    _M = new_tab(0, 3)
+local _M = new_tab(0, 3)
+local ngx_mt = new_tab(0, 2)
 
 
-    local ngx_magic_key_getters = new_tab(0, 4)
-    local ngx_magic_key_setters = new_tab(0, 2)
+if subsystem == "http" then
+    ngx_magic_key_getters = new_tab(0, 4)
+    ngx_magic_key_setters = new_tab(0, 2)
 
-
-    local function register_getter(key, func)
-        ngx_magic_key_getters[key] = func
-    end
-    _M.register_ngx_magic_key_getter = register_getter
+elseif subsystem == "stream" then
+    ngx_magic_key_getters = new_tab(0, 2)
+    ngx_magic_key_setters = new_tab(0, 1)
+end
 
 
-    local function register_setter(key, func)
-        ngx_magic_key_setters[key] = func
-    end
-    _M.register_ngx_magic_key_setter = register_setter
+local function register_getter(key, func)
+    ngx_magic_key_getters[key] = func
+end
+_M.register_ngx_magic_key_getter = register_getter
 
 
-    local mt = new_tab(0, 2)
+local function register_setter(key, func)
+    ngx_magic_key_setters[key] = func
+end
+_M.register_ngx_magic_key_setter = register_setter
 
 
-    mt.__index = function (tb, key)
-        local f = ngx_magic_key_getters[key]
-        if f then
-            return f()
-        end
-        return rawget(tb, key)
+ngx_mt.__index = function (tb, key)
+    local f = ngx_magic_key_getters[key]
+    if f then
+        return f()
     end
+    return rawget(tb, key)
+end
 
 
-    mt.__newindex = function (tb, key, ctx)
-        local f = ngx_magic_key_setters[key]
-        if f then
-            return f(ctx)
-        end
-        return rawset(tb, key, ctx)
+ngx_mt.__newindex = function (tb, key, ctx)
+    local f = ngx_magic_key_setters[key]
+    if f then
+        return f(ctx)
     end
+    return rawset(tb, key, ctx)
+end
 
 
-    setmetatable(ngx, mt)
+setmetatable(ngx, ngx_mt)
 
 
+if subsystem == "http" then
     ffi.cdef[[
-int ngx_http_lua_ffi_get_resp_status(ngx_http_request_t *r);
-int ngx_http_lua_ffi_set_resp_status(ngx_http_request_t *r, int r);
-int ngx_http_lua_ffi_is_subrequest(ngx_http_request_t *r);
-int ngx_http_lua_ffi_headers_sent(ngx_http_request_t *r);
-int ngx_http_lua_ffi_get_conf_env(const unsigned char *name,
-    unsigned char **env_buf, size_t *name_len);
+    int ngx_http_lua_ffi_get_resp_status(ngx_http_request_t *r);
+    int ngx_http_lua_ffi_set_resp_status(ngx_http_request_t *r, int r);
+    int ngx_http_lua_ffi_is_subrequest(ngx_http_request_t *r);
+    int ngx_http_lua_ffi_headers_sent(ngx_http_request_t *r);
+    int ngx_http_lua_ffi_get_conf_env(const unsigned char *name,
+                                      unsigned char **env_buf,
+                                      size_t *name_len);
     ]]
 
 
+    ngx_lua_ffi_get_resp_status = C.ngx_http_lua_ffi_get_resp_status
     ngx_lua_ffi_get_conf_env = C.ngx_http_lua_ffi_get_conf_env
 
 
     -- ngx.status
 
-    local function get_status()
-        local r = get_request()
-
-        if not r then
-            error("no request found")
-        end
-
-        local rc = C.ngx_http_lua_ffi_get_resp_status(r)
-
-        if rc == FFI_BAD_CONTEXT then
-            error("API disabled in the current context", 2)
-        end
-
-        return rc
-    end
-    register_getter("status", get_status)
-
 
     local function set_status(status)
         local r = get_request()
@@ -132,6 +123,7 @@ int ngx_http_lua_ffi_get_conf_env(const unsigned char *name,
 
     -- ngx.is_subrequest
 
+
     local function is_subreq()
         local r = get_request()
 
@@ -152,6 +144,7 @@ int ngx_http_lua_ffi_get_conf_env(const unsigned char *name,
 
     -- ngx.headers_sent
 
+
     local function headers_sent()
         local r = get_request()
 
@@ -173,20 +166,40 @@ int ngx_http_lua_ffi_get_conf_env(const unsigned char *name,
     end
     register_getter("headers_sent", headers_sent)
 
-elseif subsystem == 'stream' then
-    _M = new_tab(0, 1)
-
-
+elseif subsystem == "stream" then
     ffi.cdef[[
-int ngx_stream_lua_ffi_get_conf_env(const unsigned char *name,
-    unsigned char **env_buf, size_t *name_len);
+    int ngx_stream_lua_ffi_get_resp_status(ngx_stream_lua_request_t *r);
+    int ngx_stream_lua_ffi_get_conf_env(const unsigned char *name,
+                                        unsigned char **env_buf,
+                                        size_t *name_len);
     ]]
 
-
+    ngx_lua_ffi_get_resp_status = C.ngx_stream_lua_ffi_get_resp_status
     ngx_lua_ffi_get_conf_env = C.ngx_stream_lua_ffi_get_conf_env
 end
 
 
+-- ngx.status
+
+
+local function get_status()
+    local r = get_request()
+
+    if not r then
+        error("no request found")
+    end
+
+    local rc = ngx_lua_ffi_get_resp_status(r)
+
+    if rc == FFI_BAD_CONTEXT then
+        error("API disabled in the current context", 2)
+    end
+
+    return rc
+end
+register_getter("status", get_status)
+
+
 do
     local _getenv = os.getenv
     local env_ptr = ffi_new("unsigned char *[1]")
diff --git a/lib/resty/core/uri.lua b/lib/resty/core/uri.lua
index af0e65572..27522e4d2 100644
--- a/lib/resty/core/uri.lua
+++ b/lib/resty/core/uri.lua
@@ -1,17 +1,26 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
-local ffi_string = ffi.string
+local ffi = require "ffi"
+local base = require "resty.core.base"
+
+
 local C = ffi.C
+local ffi_string = ffi.string
 local ngx = ngx
 local type = type
 local tostring = tostring
-local base = require "resty.core.base"
 local get_string_buf = base.get_string_buf
+local subsystem = ngx.config.subsystem
+
 
+local ngx_lua_ffi_escape_uri
+local ngx_lua_ffi_unescape_uri
+local ngx_lua_ffi_uri_escaped_length
 
-ffi.cdef[[
+
+if subsystem == "http" then
+    ffi.cdef[[
     size_t ngx_http_lua_ffi_uri_escaped_length(const unsigned char *src,
                                                size_t len);
 
@@ -20,7 +29,28 @@ ffi.cdef[[
 
     size_t ngx_http_lua_ffi_unescape_uri(const unsigned char *src,
                                          size_t len, unsigned char *dst);
-]]
+    ]]
+
+    ngx_lua_ffi_escape_uri = C.ngx_http_lua_ffi_escape_uri
+    ngx_lua_ffi_unescape_uri = C.ngx_http_lua_ffi_unescape_uri
+    ngx_lua_ffi_uri_escaped_length = C.ngx_http_lua_ffi_uri_escaped_length
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    size_t ngx_stream_lua_ffi_uri_escaped_length(const unsigned char *src,
+                                                 size_t len);
+
+    void ngx_stream_lua_ffi_escape_uri(const unsigned char *src, size_t len,
+                                       unsigned char *dst);
+
+    size_t ngx_stream_lua_ffi_unescape_uri(const unsigned char *src,
+                                           size_t len, unsigned char *dst);
+    ]]
+
+    ngx_lua_ffi_escape_uri = C.ngx_stream_lua_ffi_escape_uri
+    ngx_lua_ffi_unescape_uri = C.ngx_stream_lua_ffi_unescape_uri
+    ngx_lua_ffi_uri_escaped_length = C.ngx_stream_lua_ffi_uri_escaped_length
+end
 
 
 ngx.escape_uri = function (s)
@@ -32,13 +62,13 @@ ngx.escape_uri = function (s)
         end
     end
     local slen = #s
-    local dlen = C.ngx_http_lua_ffi_uri_escaped_length(s, slen)
+    local dlen = ngx_lua_ffi_uri_escaped_length(s, slen)
     -- print("dlen: ", tonumber(dlen))
     if dlen == slen then
         return s
     end
     local dst = get_string_buf(dlen)
-    C.ngx_http_lua_ffi_escape_uri(s, slen, dst)
+    ngx_lua_ffi_escape_uri(s, slen, dst)
     return ffi_string(dst, dlen)
 end
 
@@ -54,7 +84,7 @@ ngx.unescape_uri = function (s)
     local slen = #s
     local dlen = slen
     local dst = get_string_buf(dlen)
-    dlen = C.ngx_http_lua_ffi_unescape_uri(s, slen, dst)
+    dlen = ngx_lua_ffi_unescape_uri(s, slen, dst)
     return ffi_string(dst, dlen)
 end
 
diff --git a/lib/resty/core/var.lua b/lib/resty/core/var.lua
index ff2fa158e..ea9c7635a 100644
--- a/lib/resty/core/var.lua
+++ b/lib/resty/core/var.lua
@@ -1,20 +1,27 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
+local ffi = require "ffi"
 local base = require "resty.core.base"
 
+
+local C = ffi.C
 local ffi_new = ffi.new
 local ffi_str = ffi.string
-local C = ffi.C
 local type = type
+local error = error
+local tostring = tostring
+local setmetatable = setmetatable
 local get_request = base.get_request
 local get_string_buf = base.get_string_buf
 local get_size_ptr = base.get_size_ptr
 local new_tab = base.new_tab
-local error = error
-local tostring = tostring
-local setmetatable = setmetatable
+local subsystem = ngx.config.subsystem
+
+
+local ngx_lua_ffi_var_get
+local ngx_lua_ffi_var_set
+
 
 local ERR_BUF_SIZE = 256
 
@@ -22,7 +29,8 @@ local ERR_BUF_SIZE = 256
 ngx.var = new_tab(0, 0)
 
 
-ffi.cdef[[
+if subsystem == "http" then
+    ffi.cdef[[
     int ngx_http_lua_ffi_var_get(ngx_http_request_t *r,
         const char *name_data, size_t name_len, char *lowcase_buf,
         int capture_id, char **value, size_t *value_len, char **err);
@@ -31,7 +39,26 @@ ffi.cdef[[
         const unsigned char *name_data, size_t name_len,
         unsigned char *lowcase_buf, const unsigned char *value,
         size_t value_len, unsigned char *errbuf, size_t *errlen);
-]]
+    ]]
+
+    ngx_lua_ffi_var_get = C.ngx_http_lua_ffi_var_get
+    ngx_lua_ffi_var_set = C.ngx_http_lua_ffi_var_set
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    int ngx_stream_lua_ffi_var_get(ngx_stream_lua_request_t *r,
+        const char *name_data, size_t name_len, char *lowcase_buf,
+        int capture_id, char **value, size_t *value_len, char **err);
+
+    int ngx_stream_lua_ffi_var_set(ngx_stream_lua_request_t *r,
+        const unsigned char *name_data, size_t name_len,
+        unsigned char *lowcase_buf, const unsigned char *value,
+        size_t value_len, unsigned char *errbuf, size_t *errlen);
+    ]]
+
+    ngx_lua_ffi_var_get = C.ngx_stream_lua_ffi_var_get
+    ngx_lua_ffi_var_set = C.ngx_stream_lua_ffi_var_set
+end
 
 
 local value_ptr = ffi_new("unsigned char *[1]")
@@ -47,8 +74,8 @@ local function var_get(self, name)
     local value_len = get_size_ptr()
     local rc
     if type(name) == "number" then
-        rc = C.ngx_http_lua_ffi_var_get(r, nil, 0, nil, name, value_ptr,
-                                        value_len, errmsg)
+        rc = ngx_lua_ffi_var_get(r, nil, 0, nil, name, value_ptr, value_len,
+                                 errmsg)
 
     else
         if type(name) ~= "string" then
@@ -58,8 +85,8 @@ local function var_get(self, name)
         local name_len = #name
         local lowcase_buf = get_string_buf(name_len)
 
-        rc = C.ngx_http_lua_ffi_var_get(r, name, name_len, lowcase_buf, 0,
-                                        value_ptr, value_len, errmsg)
+        rc = ngx_lua_ffi_var_get(r, name, name_len, lowcase_buf, 0, value_ptr,
+                                 value_len, errmsg)
     end
 
     -- ngx.log(ngx.WARN, "rc = ", rc)
@@ -104,8 +131,8 @@ local function var_set(self, name, value)
     end
 
     local errbuf = lowcase_buf + name_len
-    local rc = C.ngx_http_lua_ffi_var_set(r, name, name_len, lowcase_buf,
-                                          value, value_len, errbuf, errlen)
+    local rc = ngx_lua_ffi_var_set(r, name, name_len, lowcase_buf, value,
+                                   value_len, errbuf, errlen)
 
     -- ngx.log(ngx.WARN, "rc = ", rc)
 
diff --git a/lib/resty/core/worker.lua b/lib/resty/core/worker.lua
index 150e32f6c..c336debdb 100644
--- a/lib/resty/core/worker.lua
+++ b/lib/resty/core/worker.lua
@@ -1,37 +1,64 @@
 -- Copyright (C) Yichun Zhang (agentzh)
 
 
-local ffi = require 'ffi'
+local ffi = require "ffi"
 local base = require "resty.core.base"
 
 
 local C = ffi.C
 local new_tab = base.new_tab
+local subsystem = ngx.config.subsystem
+
+
+local ngx_lua_ffi_worker_id
+local ngx_lua_ffi_worker_pid
+local ngx_lua_ffi_worker_count
+local ngx_lua_ffi_worker_exiting
 
 
 ngx.worker = new_tab(0, 4)
 
 
-ffi.cdef[[
-int ngx_http_lua_ffi_worker_pid(void);
-int ngx_http_lua_ffi_worker_exiting(void);
-int ngx_http_lua_ffi_worker_id(void);
-int ngx_http_lua_ffi_worker_count(void);
-]]
+if subsystem == "http" then
+    ffi.cdef[[
+    int ngx_http_lua_ffi_worker_id(void);
+    int ngx_http_lua_ffi_worker_pid(void);
+    int ngx_http_lua_ffi_worker_count(void);
+    int ngx_http_lua_ffi_worker_exiting(void);
+    ]]
+
+    ngx_lua_ffi_worker_id = C.ngx_http_lua_ffi_worker_id
+    ngx_lua_ffi_worker_pid = C.ngx_http_lua_ffi_worker_pid
+    ngx_lua_ffi_worker_count = C.ngx_http_lua_ffi_worker_count
+    ngx_lua_ffi_worker_exiting = C.ngx_http_lua_ffi_worker_exiting
+
+elseif subsystem == "stream" then
+    ffi.cdef[[
+    int ngx_stream_lua_ffi_worker_id(void);
+    int ngx_stream_lua_ffi_worker_pid(void);
+    int ngx_stream_lua_ffi_worker_count(void);
+    int ngx_stream_lua_ffi_worker_exiting(void);
+    ]]
+
+    ngx_lua_ffi_worker_id = C.ngx_stream_lua_ffi_worker_id
+    ngx_lua_ffi_worker_pid = C.ngx_stream_lua_ffi_worker_pid
+    ngx_lua_ffi_worker_count = C.ngx_stream_lua_ffi_worker_count
+    ngx_lua_ffi_worker_exiting = C.ngx_stream_lua_ffi_worker_exiting
+end
 
 
 function ngx.worker.exiting()
-    return C.ngx_http_lua_ffi_worker_exiting() ~= 0
+    return ngx_lua_ffi_worker_exiting() ~= 0
 end
 
 
 function ngx.worker.pid()
-    return C.ngx_http_lua_ffi_worker_pid()
+    return ngx_lua_ffi_worker_pid()
 end
 
 
 function ngx.worker.id()
-    local id = C.ngx_http_lua_ffi_worker_id()
+    local id = ngx_lua_ffi_worker_id()
     if id < 0 then
         return nil
     end
@@ -41,7 +68,7 @@ end
 
 
 function ngx.worker.count()
-    return C.ngx_http_lua_ffi_worker_count()
+    return ngx_lua_ffi_worker_count()
 end
 
 
diff --git a/t/stream/os-getenv.t b/t/stream/os-getenv.t
index 5816f37ab..d41e52241 100644
--- a/t/stream/os-getenv.t
+++ b/t/stream/os-getenv.t
@@ -2,7 +2,7 @@
 use lib '.';
 use t::TestCore::Stream;
 
-plan tests => repeat_each() * (blocks() * 2 + 2);
+plan tests => repeat_each() * (blocks() * 2 + 1);
 
 $ENV{TEST_NGINX_BAR} = 'world';
 $ENV{TEST_NGINX_LUA_PACKAGE_PATH} = "$t::TestCore::Stream::lua_package_path";
@@ -154,81 +154,38 @@ in content:\s+
 
 
 === TEST 8: os.getenv() overwrite is reverted in worker phases
---- stream_config
-    lua_package_path "$TEST_NGINX_LUA_PACKAGE_PATH";
-    lua_load_resty_core off;
-
-    init_by_lua_block {
-        package.loaded.os_getenv = os.getenv
-        require "resty.core"
-        package.loaded.is_os_getenv = os.getenv == package.loaded.os_getenv
-    }
---- stream_server_config
-    content_by_lua_block {
-        os.getenv("")
-
-        ngx.say("in init: ", package.loaded.is_os_getenv, "\n",
-                "in content: ", os.getenv == package.loaded.os_getenv)
-    }
---- stream_response
-in init: false
-in content: true
-
-
-
-=== TEST 9: os.getenv() can be localized before loading resty.core
 --- main_config
 env FOO=hello;
 --- stream_config
     lua_package_path "$TEST_NGINX_LUA_PACKAGE_PATH";
-    lua_load_resty_core off;
 
     init_by_lua_block {
-        package.loaded.os_getenv = os.getenv
-        require "resty.core"
-
-        do
-            local getenv = os.getenv
-
-            package.loaded.f = function ()
-                ngx.log(ngx.NOTICE, "FOO: ", getenv("FOO"))
-            end
-        end
-
-        package.loaded.f()
-
-        package.loaded.is_os_getenv = os.getenv == package.loaded.os_getenv
+        package.loaded.init_os_getenv = os.getenv
     }
 --- stream_server_config
     content_by_lua_block {
-        package.loaded.f()
-        package.loaded.f()
+        ngx.say("FOO=", os.getenv("FOO"))
 
-        ngx.say("in init: ", package.loaded.is_os_getenv, "\n",
-                "in content: ", os.getenv == package.loaded.os_getenv)
+        if os.getenv ~= package.loaded.init_os_getenv then
+            ngx.say("os.getenv() overwrite was reverted")
+
+        else
+            ngx.say("os.getenv() overwrite was not reverted")
+        end
     }
 --- stream_response
-in init: false
-in content: true
---- grep_error_log eval
-qr/FOO: [a-z]+/
---- grep_error_log_out
-FOO: hello
-FOO: hello
-FOO: hello
+FOO=hello
+os.getenv() overwrite was reverted
 
 
 
-=== TEST 10: os.getenv() can be localized after loading resty.core
+=== TEST 9: os.getenv() can be localized after loading resty.core
 --- main_config
 env FOO=hello;
 --- stream_config
     lua_package_path "$TEST_NGINX_LUA_PACKAGE_PATH";
-    lua_load_resty_core off;
 
     init_by_lua_block {
-        package.loaded.os_getenv = os.getenv
-
         do
             local getenv = os.getenv
 
@@ -248,15 +205,18 @@ env FOO=hello;
         package.loaded.f()
         package.loaded.f()
 
-        ngx.say("in init: ", package.loaded.is_os_getenv, "\n",
-                "in content: ", os.getenv == package.loaded.os_getenv)
+        if os.getenv ~= package.loaded.init_os_getenv then
+            ngx.say("os.getenv() overwrite was reverted")
+
+        else
+            ngx.say("os.getenv() overwrite was not reverted")
+        end
     }
 --- stream_response
-in init: false
-in content: false
+os.getenv() overwrite was reverted
 --- grep_error_log eval
 qr/FOO: [a-z]+/
 --- grep_error_log_out
-FOO: nil
+FOO: hello
 FOO: hello
 FOO: hello