* Mac OS - Known to work, but may be slight hiccups
* Windows - Known to compile, but working status unknown, and not a focus for the development team at present. Note that no mining plugins will be present on a Windows system after building Grin.
The instructions below will assume a Linux system.
## Build Prerequisites
In order to compile and run Grin on your machine, you should have installed:
*<b>cmake</b> - 3.2 or greater should be installed and on your $PATH. Used by the build to compile the mining plugins found in the included [Cuckoo Miner](https://github.com/mimblewimble/cuckoo-miner)
*<b>Rust</b> - 1.21.0 or greater via [Rustup](https://www.rustup.rs/) - Can be installed via your package manager or manually via the following commands:
If you're having issues with building cuckoo-miner plugins (which will usually manifest as a lot of C errors when building the `grin_pow` crate, you can turn mining plugin builds off by editing the file `pow/Cargo.toml' as follows:
```
#uncomment this feature to turn off plugin builds
features=["no-plugin-build"]
```
This may help when building on 32 bit systems or non x86 architectures. You can still use the internal miner to mine by setting:
Provided all of the prerequisites were installed and there were no issues, there should be 3 things in your project directory that you need to pay attention to in order to configure and run grin. These are:
* The Grin binary, which should be located in your project directory as target/debug/grin
* A set of mining plugins, which should be in the 'plugins' directory located next to the grin executable
Grin is currently configured via a combination of configuration file and command line switches, with any provided switches overriding the contents of the configuration file. To see a list of commands and switches use:
```
grin help
```
At startup, grin looks for a configuration file called 'grin.toml' in the following places in the following order, using the first one it finds:
* The current working directory
* The directory in which the grin executable is located
* {USER_HOME}/.grin
If no configuration file is found, command line switches must be given to grin in order to start it. If a configuration file is found but no command line switches are provided, grin starts in server mode using the values found in the configuration file.
At present, the relevant modes of operation are 'server' and 'wallet'. When running in server mode, any command line switches provided will override the values found in the configuration file. Running in wallet mode does not currently use any values from the configuration file other than logging output parameters.
For a basic example simulating a single node network, create a directory called 'node1' and change your working directory to it. You'll use this directory to run a wallet and create a new blockchain via a server running in mining mode.
You'll need a config file - the easiest is to copy over the grin.toml file from the root grin directory into the node1 directory you just made.
Before running your mining server, a wallet server needs to be set up and listening so that the mining server knows where to send mining rewards. Do this from the first node directory with the following commands:
node1$ grin wallet init
node1$ grin wallet -p "password" listen
See [wallet](wallet.md) for more info on the various Grin wallet commands and options.
This will create a wallet server listening on the default port 13415 with the password "password". Next, in another terminal window in the 'node1' directory, run a full mining node with the following command:
node1$ grin server -m run
This creates a new .grin database directory in the current directory, and begins mining new blocks (with no transactions, for now). Note this starts two services listening on two default ports,
port 13414 for the peer-to-peer (P2P) service which keeps all nodes synchronized, and 13413 for the Rest API service used to verify transactions and post new transactions to the pool (for example). These ports can be configured via command line switches, or via a grin.toml file in the working directory.
Let the mining server find a few blocks, then stop (just ctrl-c) the mining server and the wallet server. You'll notice grin has created a database directory (.grin) in which the blockchain and peer data is stored. There should also be a wallet.dat file in the current directory, which contains a few coinbase mining rewards created each time the server mines a new block.
After following the instructions above to build a testnet executable and ensuring it's on your system path, create two directories wherever you prefer. Call one 'wallet' and one 'server'.
