# Table of Contents
1. [Library Requirements](#library-requirements)
2. [Ubuntu](#to-build-on-ubuntu)
3. [Fedora](#to-build-on-fedora)
4. [FreeBSD](#to-build-on-freebsd)
5. [NixOS](#to-build-on-nixos)
6. [macOS](#to-build-on-macos)
7. [Android](#to-cross-compile-for-android)
8. [Raspberry Pi](#to-cross-compile-for-raspberry-pi)
9. [Additional steps](#additional-steps)

Library Requirements
--------------------

You will need several development libraries:
* libsqlite3: for database support.
* libgmp: for secp256k1

For actually doing development and running the tests, you will also need:
* pip3: to install python-bitcoinlib
* asciidoc: for formatting the man pages (if you change them)
* valgrind: for extra debugging checks

You will also need a version of bitcoind with segregated witness and
estimatesmartfee economical node, such as the 0.15 or above.

To Build on Ubuntu
---------------------

OS version: Ubuntu 15.10 or above

Get dependencies:

    sudo apt-get update
    sudo apt-get install -y \
      autoconf automake build-essential git libtool libgmp-dev \
      libsqlite3-dev python python3 net-tools

If you don't have Bitcoin installed locally you'll need to install that
as well:

    sudo apt-get install software-properties-common
    sudo add-apt-repository ppa:bitcoin/bitcoin
    sudo apt-get update
    sudo apt-get install -y bitcoind

For development or running tests, get additional dependencies:

    sudo apt-get install -y asciidoc valgrind python3-pip
    sudo pip3 install python-bitcoinlib

Clone lightning:

    git clone https://github.com/ElementsProject/lightning.git
    cd lightning

Build lightning:

    make

Running lightning:

    bitcoind &
    ./lightningd/lightningd &
    ./cli/lightning-cli help

**Note**: You may need to include `testnet=1` in `bitcoin.conf`

To Build on Fedora
---------------------

OS version: Fedora 27 or above

Get dependencies:
```
$ sudo dnf update -y && \
        dnf groupinstall -y \
                'C Development Tools and Libraries' \
                'Development Tools' && \
        dnf install -y \
                clang \
                gmp-devel \
                libsq3-devel \
                python2-devel \
                python3-devel \
                python3-pip \
                python3-setuptools \
                net-tools \
                net-tools \
                valgrind \
                wget && \
        dnf clean all
```

Make sure you have [bitcoind](https://github.com/bitcoin/bitcoin) available to run

Clone lightning:
```
$ git clone https://github.com/ElementsProject/lightning.git
$ cd lightning
```

Build and install lightning:
```
$lightning> make
$lightning> sudo make install
```

Running lightning (mainnet):
```
$ bitcoind &
$ lightningd --network=bitcoin
```

Running lightning on testnet:
```
$ bitcoind -testnet &
$ lightningd --network=testnet
```

To Build on FreeBSD
---------------------

OS version: FreeBSD 11.1-RELEASE or above

Get dependencies:

    # pkg install -y \
      autoconf automake git gmp asciidoc gmake libtool python python3 sqlite3

If you don't have Bitcoin installed locally you'll need to install that
as well:

    # pkg install -y bitcoin-daemon bitcoin-utils

Clone lightning:

    $ git clone https://github.com/ElementsProject/lightning.git
    $ cd lightning

Build lightning:

    $ gmake
    $ gmake install

Running lightning:

**Note**: Edit your `/usr/local/etc/bitcoin.conf` to include
`rpcuser=<foo>` and `rpcpassword=<bar>` first, you may also need to
include `testnet=1`

    # service bitcoind start
    $ ./lightningd/lightningd &
    $ ./cli/lightning-cli help

To Build on NixOS
--------------------

Use nix-shell launch a shell with a full clightning dev environment:

```
$ nix-shell -Q -p gdb sqlite autoconf git clang libtool gmp sqlite autoconf \
autogen automake 'python3.withPackages (p: [p.bitcoinlib])' \
valgrind asciidoc --run make
```

To Build on macOS
---------------------

Assume you have Xcode and HomeBrew installed on your Mac.
Get dependencies:

    $ brew install autoconf automake libtool python3 gmp gnu-sed

If you don't have bitcoind installed locally you'll need to install that
as well:

    $ brew install \
    berkeley-db4 boost miniupnpc openssl pkg-config protobuf qt libevent
    $ git clone https://github.com/bitcoin/bitcoin
    $ cd bitcoin
    $ ./autogen.sh
    $ ./configure
    $ make & make install

Clone lightning:

    $ git clone https://github.com/ElementsProject/lightning.git
    $ cd lightning

Build lightning:

    $ make

Running lightning:

**Note**: Edit your `~/Library/Application\ Support/Bitcoin/bitcoin.conf`
to include `rpcuser=<foo>` and `rpcpassword=<bar>` first, you may also
need to include `testnet=1`

    bitcoind &
    ./lightningd/lightningd &
    ./cli/lightning-cli help

To cross-compile for Android
--------------------

Make a standalone toolchain as per
https://developer.android.com/ndk/guides/standalone_toolchain.html.
For c-lightning you must target an API level of 24 or higher.

Depending on your toolchain location and target arch, source env variables
such as:

    export PATH=$PATH:/path/to/android/toolchain/bin
    # Change next line depending on target device arch
    target_host=arm-linux-androideabi
    export AR=$target_host-ar
    export AS=$target_host-clang
    export CC=$target_host-clang
    export CXX=$target_host-clang++
    export LD=$target_host-ld
    export STRIP=$target_host-strip

Two makefile targets should not be cross-compiled so we specify a native CC:

    make CC=clang clean ccan/tools/configurator/configurator
    make clean -C ccan/ccan/cdump/tools \
      && make CC=clang -C ccan/ccan/cdump/tools

Install the `qemu-user` package.
This will allow you to properly configure
the build for the target device environment.
Build with:

    BUILD=x86_64 HOST=arm-linux-androideabi \
      make PIE=1 DEVELOPER=0 \
      CONFIGURATOR_CC="arm-linux-androideabi-clang -static"

To cross-compile for Raspberry Pi
--------------------

Obtain the [official Raspberry Pi toolchains](https://github.com/raspberrypi/tools). This document assumes compilation will occur towards the Raspberry Pi 3 (arm-linux-gnueabihf as of Mar. 2018). In addition, obtain and install cross-compiled versions of sqlite 3 and gmp.

Depending on your toolchain location and target arch, source env variables will need to be set. They can be set from the command line as such:

    export PATH=$PATH:/path/to/arm-linux-gnueabihf/bin
    # Change next line depending on specific Raspberry Pi device
    target_host=arm-linux-gnueabihf
    export AR=$target_host-ar
    export AS=$target_host-as
    export CC=$target_host-gcc
    export CXX=$target_host-g++
    export LD=$target_host-ld
    export STRIP=$target_host-strip

Install the `qemu-user` package. This will allow you to properly configure the build for the target device environment. Then, build with the following commands. (A 64-bit build system is assumed here.)

    make CC=gcc clean ccan/tools/configurator/configurator
    BUILD=x86_64 HOST=arm-linux-gnueabihf make PIE=1 DEVELOPER=0 CONFIGURATOR_CC="arm-linux-gnueabihf-gcc -static" LDFLAGS="-L/path/to/gmp-and-sqlite/lib" CFLAGS="-std=gnu11 -I /path/to/gmp-and-sqlite/include -I . -I ccan -I external/libwally-core/src/secp256k1/include -I external/libsodium/src/libsodium/include -I external/jsmn -I external/libwally-core/include -I external/libbacktrace -I external/libbase58"

The compilation will eventually fail due to a compile error in the `cdump` CCAN module. Recompile the module, and then re-run the make system.

    make clean -C ccan/ccan/cdump/tools
    make CC=gcc -C ccan/ccan/cdump/tools
    BUILD=x86_64 HOST=arm-linux-gnueabihf make PIE=1 DEVELOPER=0 CONFIGURATOR_CC="arm-linux-gnueabihf-gcc -static" LDFLAGS="-L/path/to/gmp-and-sqlite/lib" CFLAGS="-std=gnu11 -I /path/to/gmp-and-sqlite/include -I . -I ccan -I external/libwally-core/src/secp256k1/include -I external/libsodium/src/libsodium/include -I external/jsmn -I external/libwally-core/include -I external/libbacktrace -I external/libbase58"

Additional steps
--------------------
Go to [README](https://github.com/ElementsProject/lightning/blob/master/README.md) for more information how to create an address, add funds, connect to a node, etc.
