1  # OpenBSD Build Guide
  2  
  3  **Updated for OpenBSD [7.8](https://www.openbsd.org/78.html)**
  4  
  5  This guide describes how to build bitcoind, command-line utilities, and GUI on OpenBSD.
  6  
  7  ## Preparation
  8  
  9  ### 1. Install Required Dependencies
 10  Run the following as root to install the base dependencies for building.
 11  
 12  ```bash
 13  pkg_add git cmake boost libevent
 14  ```
 15  
 16  SQLite is required for the wallet:
 17  
 18  ```bash
 19  pkg_add sqlite3
 20  ```
 21  
 22  To build Bitcoin Core without the wallet, use `-DENABLE_WALLET=OFF`.
 23  
 24  Cap'n Proto is needed for IPC functionality (see [multiprocess.md](multiprocess.md)):
 25  
 26  ```bash
 27  pkg_add capnproto
 28  ```
 29  
 30  Compile with `-DENABLE_IPC=OFF` if you do not need IPC functionality.
 31  
 32  See [dependencies.md](dependencies.md) for a complete overview.
 33  
 34  ### 2. Clone Bitcoin Repo
 35  Clone the Bitcoin Core repository to a directory. All build scripts and commands will run from this directory.
 36  ``` bash
 37  git clone https://github.com/bitcoin/bitcoin.git
 38  ```
 39  
 40  ### 3. Install Optional Dependencies
 41  
 42  #### GUI Dependencies
 43  ###### Qt6
 44  
 45  Bitcoin Core includes a GUI built with the cross-platform Qt Framework. To compile the GUI, we need to install
 46  the necessary parts of Qt, the libqrencode and pass `-DBUILD_GUI=ON`. Skip if you don't intend to use the GUI.
 47  
 48  ```bash
 49  pkg_add qt6-qtbase qt6-qttools
 50  ```
 51  
 52  ###### libqrencode
 53  
 54  The GUI will be able to encode addresses in QR codes unless this feature is explicitly disabled. To install libqrencode, run:
 55  
 56  ```bash
 57  pkg_add libqrencode
 58  ```
 59  
 60  Otherwise, if you don't need QR encoding support, use the `-DWITH_QRENCODE=OFF` option to disable this feature in order to compile the GUI.
 61  
 62  ---
 63  
 64  #### Notifications
 65  ###### ZeroMQ
 66  
 67  Bitcoin Core can provide notifications via ZeroMQ. If the package is installed, support will be compiled in.
 68  ```bash
 69  pkg_add zeromq
 70  ```
 71  
 72  #### Test Suite Dependencies
 73  There is an included test suite that is useful for testing code changes when developing.
 74  To run the test suite (recommended), you will need to have Python 3 installed:
 75  
 76  ```bash
 77  pkg_add python py3-zmq  # Select the newest version of the python package if necessary.
 78  ```
 79  
 80  ## Building Bitcoin Core
 81  
 82  ### 1. Configuration
 83  
 84  There are many ways to configure Bitcoin Core, here are a few common examples:
 85  
 86  ##### Wallet and GUI:
 87  This enables wallet support and the GUI, assuming SQLite and Qt 6 are installed.
 88  
 89  ```bash
 90  cmake -B build -DBUILD_GUI=ON
 91  ```
 92  
 93  Run `cmake -B build -LH` to see the full list of available options.
 94  
 95  ### 2. Compile
 96  
 97  ```bash
 98  cmake --build build     # Append "-j N" for N parallel jobs.
 99  ctest --test-dir build  # Append "-j N" for N parallel tests.
100  ```
101  
102  ## Resource limits
103  
104  If the build runs into out-of-memory errors, the instructions in this section
105  might help.
106  
107  The standard ulimit restrictions in OpenBSD are very strict:
108  ```bash
109  data(kbytes)         1572864
110  ```
111  
112  This is, unfortunately, in some cases not enough to compile some `.cpp` files in the project,
113  (see issue [#6658](https://github.com/bitcoin/bitcoin/issues/6658)).
114  If your user is in the `staff` group the limit can be raised with:
115  ```bash
116  ulimit -d 3000000
117  ```
118  The change will only affect the current shell and processes spawned by it. To
119  make the change system-wide, change `datasize-cur` and `datasize-max` in
120  `/etc/login.conf`, and reboot.