Installing Lazarus on Linux

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This page is about installing FPC and Lazarus on a Linux system. Its intended for new and 'regular' users, it does not cover some very advanced methods and concentrates on current releases. Linux users should think of FPC and Lazarus as being two distinct but related processes, FPC does not change much, on the other hand, you will probably want to update your Lazarus install or perhaps install multiple Lazarus versions. Mixing the install methods, especially after V2.0 may cause problems so please read carefully.

Notes about terms used on this page -

  • We refer to various downloadable files such as fpc_something - you should replace the 'something' with whats appropriate for your system, for example, early 2019 using a DEB based 64bit distro it might be fpc-laz_3.0.4-1_amd64.deb. Mid 2021 lazarus-something.deb is lazarus-project_2.0.12-0_amd64.deb.
  • Package Manager means a range of things on different different Linux systems. While we give command line examples, thats just because its easier to write. You will get the same result if you use your favourite GUI Tool such as Synaptic, Ubuntu Software Centre or YaST2. Maybe try double clicking on a downloaded package in your file manager.
  • What ever Package manager tool you use, make sure you are using one that resolves dependencies (that is, it also installs thing that are required by the main package you are installing), most GUI apps do. You should avoid using tools like dpkg or rpm and instead use apt or yum depending on your flavour of Linux.

Required Linux packages

According to forum member "MarkMLl", required Debian packages for Lazarus are:

  • build-essential
  • gdb (see below)
  • libgpm-dev (formerly libgpmg1-dev)
  • libncurses5-dev
  • libncursesw5-dev

Additionally, some distribution may also require appmenu-gtk2-module. If you find starting Lazarus has a 20 odd second delay, do try this additional package. Seems to be a particular problem on Ubuntu.


Linux (and Windows) users on Intel or AMD processors can use FPDebug backend (or, more correctly, FPDebug internal Dwarf-Debugger) and for most users that's a good choice. It's reported to be faster and in some respects, more feature rich than gdb. And it's bundled in with Lazarus.

If it's not auto selected (perhaps because you also have gdb installed), in Lazarus, Tool->Options->Debugger->Debugger-Backend. Click the "Change Type" button and select "FPDebug internal Dwarf-Debugger".

Other platforms, or perhaps users with specific needs ( see,55131.msg417949.html#msg417949 ) will need to stick with gdb.

Make a Choice

You do need to decide, early on, where you will be getting your Lazarus install from. You can, at any stage change your mind but at the cost of some backtracking. We don't recomend you get your FPC and Lazarus install kits from different places, its sometimes possible but sometimes unreliable. Broadly, your choices are -

  • Use your Package Manager to install both FPC and Lazarus. This means you are locked into the version of Lazarus that your distribution maintainers offer. Due to distro and Lazarus release cycles being out of sync, at any one time, its unlikely that your distribution will have the latest release of Lazarus. And many users do find those new releases attractive. You can install only one version of Lazarus under this model. But on the other hand, using the package manager approach is very easy and probably suits casual users.
  • Use the pre compiled packages (both FPC and Lazarus) made available by the FPC/Lazarus Team at SourceForge. Here you will find a wide choice of matched versions but you can only install one version at a time. The install process is still very easy ! This is possibly the best bet for new users.
  • Install FPC from either your Package Manager or SourceForge and then download the Lazarus source code and compile it yourself. May take a touch longer but is almost as easy and you do end up with the ability to add extra Lazarus installs, perhaps a 'production' version and a version based on the next release candidate. Or an old version to work on legacy code. In addition, you can easily make your own changes to the Lazarus Component Library, maybe just debug statements, maybe additional features you can feed back to help improve Lazarus further.
  • Use FPCUPdeluxe - it can install a range of versions of both FPC and Lazarus for you without requiring you to understand the underlying structure.

The Package Manager Model

If you are happy with the versions offered by your distribution this might be the way to go. Almost all Linux distributions come with some sort of Package Manager, you are probably familiar with your's. Between then, the DEB and RPM based package systems represent much of the Linux community. And if you soon run into the limitations of this model, your package manager will help you back out again. But first, check the version available. Look up 'lazarus' in your GUI Package Manager or do -

// DEB Users -
apt-cache policy lazarus

// RPM User -
yum search lazarus

Note the names as well as the versions, we need three packages, fpc-something, fpc-source-something and, finally lazarus_something. Assuming you distribution's package has its dependencies set up correctly, all you need do is choose to install Lazarus in either your Package Manage GUI or do:

// DEB Users -
sudo apt-get install lazarus

// RPM Users -
sudo yum install lazarus

// or
sudo dnf install lazarus

Notes :

  • Some distro prepared packages do not include the tools necessary to add cross compiling to its capabilities. If you may want to cross compile in the future, please consider one of the next listed models.
  • Some distro package managers break Lazarus up in small 'chunks', by default you get the GTK2 chunks. If you plan to use Qt5 also install libqt5pas-dev and lcl-qt5. You can make Qt5 apps using the GTK2 IDE.
  • If you plan to work with GTK3, you will need to install libgtk-3-dev, its not declared as a dependency of Lazarus yet because the GTK3 interface is not, yet, complete.
  • If you use Debian Bullseye, you should consider getting Lazarus (2.2.0) from Bullseye-Backports, there is an annoying bug in the main repo version that affects IDE rebuilding. Other Debian based distros will probably pick up the Backport or Testing version and they will be fine.

Debian-based 64-bit with Lazarus 32-bit

On Debian system, like Ubuntu or Mint, run in terminal:

sudo dpkg --add-architecture i386
sudo apt-get update

And then install the FPC-Lazarus i386 deb-packages in right order:

  • fpc-laz first
  • fpc-src next
  • finally lazarus-project

If you have error message like "cannot find GCC", then run in terminal:

sudo apt-get install -y gcc:i386

FPC and Lazarus from SourceForge

If your Package Manager cannot offer you the correct version of FPC then probably SourceForge can (The Raspberry Pi being a notable exception) (! But be prepared for your package manager to complain about being bypassed, just insist you know what you are doing !

All packages can be found at , if you want just FPC, you will find it down in the corresponding Lazarus release directory.

Navigate down, select the appropriate packages, again, fpc_something, fpc-src_something and lazarus_something, save them locally and install. WARNING, very important, this catches many users out ! Like most Linux packages, these packages have dependencies, you must install using a tool that resolves dependencies. Commands like "dpkg -i fpc_something.deb" will, most definitely leave an incomplete installation !

Further, you might need to manually install gdb, the GNU debugger if you are not going to use fpdebug. A debugger is not absolutely essential but it makes life a lot easier. If you plan to work with GTK3, or Qt5 you will need to manually install libgtk-3-dev or libqt5pas-dev.

On a DEB based System. On a older DEB based system, you almost certainly should use gdebi to install any downloaded DEB. It might already be installed, if not, install it first. You can use gdebi at the command line or double click a downloaded package in your file manager. But remember, most important, install first fpc, then fpc-src, then and only then, Lazarus. On more recent deb based systems, the apt command can resolve dependencies, you could then use this command (but note the very important ./ in front of each deb file, if you don't specify the exact location of your downloaded deb file, it will go and get the repository based one) -

sudo apt install ./fpc_something.deb ./fpc-src_something.deb ./lazarus-something.deb

in mid 2022 for example, you might download from and move the files to a suitable place and then type -

sudo apt install ./fpc-laz_3.2.2-210709_amd64.deb  ./fpc-src_3.2.2-210709_amd64.deb  ./lazarus-project_2.2.0-0_amd64.deb

On an RPM Based System Installing downloaded packages at the command line as shown below. (Author is unaware of the GUI Package tool that does, in fact, resolve dependencies) -

// RPM Users -
yum localinstall fpc_something.rpm
yum localinstall fpc-src_something.rpm
yum localinstall lazarus-something.rpm

Note : later RPM based systems use the dnf command instead of yum, same syntax.

Build Lazarus from Source

Surprisingly easy, but that is because Lazarus routinely rebuilds itself, eg when a Lazarus package is added. So, its also a useful test that all required dependencies are really present. It allows you to have multiple versions of Lazarus installed ( see --pcp=xxx ) and both Lazarus and LCL are in your own disk space so no write issues. However, you will need to manually add an entry in your OS Menu system and, perhaps distinctive Lazarus icons.

Light bulb  Note: Remember, FPC and Lazarus are two, separate products. Before thinking about building Lazarus, you must have a working and tested FPC. Mid 2023 FPC 3.2.2 was what you probably should be using, many distributions will have it available, otherwise, you need to install it from one of the ways documented on Installing the Free Pascal Compiler .
Light bulb  Note: Dependencies - First and foremost, a suitable version of FPC, see above. You probably want to build the GTK2 version of Lazarus, most distros will have gtk2 preinstalled but you may need to install its dev libraries. So, install libx11-dev and libgtk2.0-dev, that will bring gtk2 itself along if necessary. Possibly (see above) gdb. If building a QT5 version, you will need libqt5pas-dev. If you are going to work with GTK3, you will need to install libgtk-3-dev
Light bulb  Note: Systems with limited memory, such as the Raspberry Pi may need you to increase swap space to at least a Gig before building Lazarus, RasPi page. See Setting Raspberry Pi Swap Size

The example here pulls down what some consider 'brave', the trunk or main development version. The same process can get you releases, fixes or release candidates. Note this is not a script, it is a series of commands, to be copied one at a time, so you can see whats happening !

Get the Lazarus Source

There are two different ways to download the Lazarus Source (since August 2021) from gitlab, in fact there are several variations of each possible too) -

As a Zip/Tar ball.

If you just want a quick snapshot of trunk, or perhaps want to test the release candidate (and that a great idea) then you may not need access to the developer capabilities that a Git install provides. So, you don't need any git tools on your local machine and its quick and easy. While you can do it through the Gitlab web interface from its easier to describe with command line tools, start by cd-ing to a suitable place, I use $HOME/bin/Lazarus, then -

git clone lazarus-main
cd lazarus-main

Some recommended downloads

You can see all these options, and lot more on the gitlab site by pulling down the dropbox, left of center, near the top of the page.

As a Git repository.

On the other hand, if you will be contributing patches, fixes, to Lazarus, or tracking down bugs by bisecting recent releases, then a proper git install is undoubtedly the way forward. You will need git installed locally, again, go to a suitable directory and:

git clone lazarus-main
cd lazarus-main

This is a bit slower process the first time, later you will use git to update it (run "git pull" from this folder "lazarus-main") and that's a lot faster. As bug reports must be tested against main, it probably does not make sense downloading git versions of anything other than main and maybe fixes.

Building Lazarus

Remembering that if you have less than 4G ram, you must set 1G or preferably 2G of swap.

cd lazarus-main    # or, where ever you have put your Lazarus source code
make clean
make bigide

You can now start Lazarus with the command ./lazarus or, if you are in another directory, something like -


You can add that directory to your path, put a script in ~/bin to start it or whatever, its Linux, you choose ! Here is an example script to put in your personal bin directory, note it includes FPC, if thats already on your path, leave that line out -

cd "$HOME/bin/Lazarus/""$RELEASE"
./lazarus --pcp="$HOME/.""$RELEASE"

Out of the box, lazarus stores its config files in $HOME/.lazarus - that might be all you need. But multiple installs require multiple config directories, thats why the --pcp switch on the command line. Alternatively, you can put a lazarus.cfg file in the top level Lazarus directory, where the lazarus binary is containing your chosen command line switch, this is a great way to ensure you don't mix up config data, lazarus does not like that !

Menu items and Icons

Building from source leaves you without the nice main menu entries and pretty icons that people who installed using packages get. But even that is easy to fix. You need two things, a suitable icon and an appropriate desktop file. Here is how -

First, download a Lazarus icon to use (its just an image, does not need to be from right version of Lazarus),

cd ~/.icons
cd -

Then create a desktop file, eg ~/.local/share/applications/lazarus.desktop that looks a bit like this

[Desktop Entry]

You will almost certainly have to change some things and might want to change more -

  • Name= - This is what will appear in your main menu.
  • Exec= - This is the path to your executable lazarus, in my case I keep my various installs in ~/bin/Lazarus, yours may be different. Its unlikely your user name is 'myusername' so please change it. Note you could add a --pcp command line switch as mentioned above. If you have multiple installs of Lazarus, make multiple desktop files and make sure each uses a separate set of config files. Most important ! You might like to point this item to the little bash script mentioned above, its an easy way of ensuring Lazarus gets the FPC path setting.
  • Icon= The full path to the icon we downloaded earlier. The icon does not need be exactly there, but its a good place.
  • Categories= This line determines which sub-menu Lazarus will show up under. As shown, its under "Programing" on my system, "GNOME;Utility" will pop it up under "Accessories".

Help Files

FPC and Lazarus have quite a wide range of help files and related resources. When building Lazarus from source, you don't get the pre installed help chm that respond, for example, when you press F1. But they are easy to add, download a zip file into, typically, a directory called 'help'. Then, in Lazarus, Tools->Options->Help->Help_Options->CHM_Help_Viewer. Set Help Files Path to the directory you just put all the Chm files into. Get these files from here -

These files are very kindly updated from time to time by Marcov. If you prefer, you can build your own in the source tree.

There are ways to access, possibly a newer version of the same data -

What does the BigIDE argument to make do?

The bigide make argument adds a bunch of packages to Lazarus that many find useful and cannot do without. The packages that are added are:

  • cairocanvas
  • chmhelp
  • datetimectrls
  • externhelp
  • fpcunit
  • fpdebug
  • instantfpc
  • jcf2
  • lazcontrols
  • lazdebuggers
  • lclextensions
  • leakview
  • macroscript
  • memds
  • onlinepackagemanager
  • pas2js
  • PascalScript
  • printers
  • projecttemplates
  • rtticontrols
  • sdf
  • sqldb
  • synedit
  • tachart
  • tdbf
  • todolist
  • turbopower_ipro
  • virtualtreeview

The above list is sourced from the [Lazarus source directory]/IDE/Makefile.fpc and may be subject to change.

Note that if you have not compiled your own Lazarus IDE with the bigide argument, you can install any of these packages yourself using the Lazarus IDE Package > Install/Uninstall Packages... dialog.


Another approach is fpcupdeluxe, its an application that you run on your computer to manage your FPC / Lazarus install. Its very suited to people who just want to get a working install quickly and are happy to allow fpcupdeluxe to do the thinking for them.

See Also

Other Relevant Pages

Testing FPC installation

See Testing the FPC Install for a very simple test that FPC is working.

If that worked, well done ! Now proceed to installing Lazarus.

Further Reading

Much discussion in a forum thread created by Handoko,,41524.0.html This forum thread may be of particular interest to people who have upgraded an existing Linux install to a more recent version (ie Ubuntu 10.04 to 18.04) as that does seem to trigger some unexpected dependency problems. Please, ask for help, document such problems here when you fix them.