diff --git a/doc/design/build_system/README.md b/doc/design/build_system/README.md
index 4c4315d6b9b305ce95a6b78154490a736a6163a3..310739f37ae48934afe1d042e87efef85b98f1fc 100644
--- a/doc/design/build_system/README.md
+++ b/doc/design/build_system/README.md
@@ -20,7 +20,7 @@ The difference between `nv_` functions and `cc_` functions is that the former us
 
 Both `nv_` and `cc_` functions enables C++11 (-std=c++11).
 
-In addition,
+Also,
 
 - to describe external dependencies, we need `external_library`.
 - to build shared libraries, we need `shared_library`.
@@ -104,7 +104,4 @@ shared_library(api
 
 ### Implementation
 
-As above example CMakeLists.txt executes, each function invocation
-adds "nodes" to a dependency graph.  It also use this graph to
-generate CMake commands including `add_executable`,
-`add_dependencies`, `target_link_libraries`, and `add_test`.
+As above example CMakeLists.txt executes, each function invocation adds "nodes" to a dependency graph.  It also use this graph to generate CMake commands including `add_executable`, `add_dependencies`, `target_link_libraries`, and `add_test`.
diff --git a/doc/design/build_system/go.md b/doc/design/build_system/go.md
deleted file mode 100644
index 90399ff70111b981bc1ccaa887214db914e1f187..0000000000000000000000000000000000000000
--- a/doc/design/build_system/go.md
+++ /dev/null
@@ -1,98 +0,0 @@
-# Design Doc: `go_{library,binary,test}`
-
-## Concerns
-
-1. Need to build Go libraries callable from Go and from C.
-
-   For usual Go libraries, the bulding command line is as
-
-   ```bash
-   go build foo.go bar.go -o libfoobar.a
-   ```
-
-   For Go libraries callable from C/C++, the command line is
-
-   ```bash
-   go build -buildmode=c-archive foo.go bar.go -o libstatic.a
-   ```
-
-   or for shared libraries:
-
-   ```bash
-   go build -buildmode=c-shared foo.go bar.go -o libdynamic.so
-   ```
-
-   and `foo.go`, `bar.go`, etc must start with a line `package main`,
-   which defines all symbols in special pacakge `main`.  There also
-   must be a `func main`, which could have empty body.
-
-1. Need to support building-in-Docker.
-
-   We are going to support two ways to building -- (1) in Ubuntu, and
-   (2) in Docker container whose base image is Ubuntu.
-
-   The challenge is (2), because to build in Docker, we run the
-   development image as:
-
-   ```bash
-   git clone https://github.com/PaddlePaddle/Paddle -o paddle
-   cd paddle
-   docker run -v $PWD:/paddle paddle:dev
-   ```
-
-   which maps the local repo to `/paddle` in the container.
-
-   This assumes that all Go code, including third-party packages, must
-   be in the local repo.  Actually, it assumes that `$GOPATH` must be
-   in the local repo.  This would affect how we write `import`
-   statemetns, and how we maintain third-party packages.
-
-
-## A Solution
-
-This might not be the optimal solution.  Comments are welcome.
-
-### Directory structure
-
-We propose the following directory structure:
-
-```
-https://github.com/PaddlePaddle/Paddle
-                                  ↓ git clone
-                         ~/work/paddle/go/pkg1/foo.go
-                                         /pkg2/bar.go
-                                         /cmd/cmd1/wee.go
-                                         /cmd/cmd2/qux.go
-                                         /github.com/someone/a_3rd_party_pkg (Git submodule to a 3rd-party pkg)
-                                         /golang.org/another_3rd_party_pkg (Git submodule to another one)
-                                      /build/go ($GOPATH, required by Go toolchain)
-                                               /src (symlink to ~/work/paddle/go/)
-                                               /pkg (libraries built by Go toolchain)
-                                               /bin (binaries bulit by Go toolchain)
-```
-
-Above figure explains how we organize Paddle's Go code:
-
-1. Go source code in Paddle is in `/go` of the repo.
-1. Each library package is a sub-directory under `/go`.
-1. Each (executable) binary package is a sub-directory under
-   `/go/cmd`.  This is the source tree convention of Go itself.
-1. Each 3rd-party Go package is a Git submodule under `/go`.
-
-These rules make sure that all Go source code are in `/go`.
-
-At build-time, Go toolchain requires a directory structure rooted at
-`$GOPATH` and having three sub-directories: `$GOPATH/src`,
-`$GOPATH/pkg`, and `$GOPATH/bin`, where `$GOPATH/src` is the source
-tree and the root of Go's `import` paths.
-
-For example, if `/go/pkg1/foo.go` contains `import
-"github.com/someone/a_3rd_party_pkg"`, the Go toolchain will find the
-package at `$GOPATH/src/github.com/someone/a_3rd_party_pkg`.
-
-In order to create such a `$GOPATH`, our build system creates
-`/build/go`.  Remeber that we want to make sure that all output files
-generated at build-time are place in `/build`.
-
-Under `/build/go`, our build system creates a symoblic link `src`
-pointing to `/go`, where all Go source code resides.