To compile sources you need Lazarus IDE (https://sourceforge.net/projects/lazarus).
Open .lpi project files and do "build all" to compile the executables.

Basically, you need to compile project_peach.lpi (PeaZip) and project_pea.lpi (Pea), on Windows you also need to compile dragdropfilesdll.lpi and copy dragdropfilesdll.dll in the same directory of PeaZip.

Please read the following documentation to understand what is contained in the source package and please see precompiled program's packages to know what third parts executables (7z, arc, paq...) are needed by PeaZip.


Source package content:


SOURCES:

- project_pea.lpi: PEA, the actual engine for PEA file format support; 
- project_peach.lpi: originally PEACH, PEAlaunCHer, that compiles to the main executable 
  PeaZip and act as GUI frontend for PEA, 7z and other utilities;
- project_demo_lib.lpi: a demo application using PEA source as a library.

dragdropfilesdll directory contains sources to build dragdropfilesdll.dll, which provides application-to-system files drag&drop functions under Windows systems, sources in this path requires installation of optional Lazarus package DragDropLazarus5.2 (or newer) to be compiled, which is based on work of Angus Johnson & Anders Melander (on Delphi), and Michael Köcher / six (on Lazarus).
The package is available in Lazarus Online Package Manager or from https://packages.lazarus-ide.org/DragDrop.zip

"installer" path contains InnoSetup script files creating Windows installers with file associations and menu integration for PeaZip.

"FreeDesktop_integration" path contain files for integration in desktop environments compliant with FreeDesktop standars (i.e. Gnome and KDE)

.res and resulting .rc files are used on Windows platform to give to the application's executables manifest and binaries information (author, version etc)


MEDIA AND DOCUMENTATION:

Readme_*.txt files contain some hints for the Windows and Linux users.

"copying.txt" is the license file for PeaZip project sources, released under LGPL.

"media" path contains graphic for PeaZip project.

"lang" path contains featured translations of application's text.

"lang-wincontext" path contains .reg files to localize app's context menus in Windows


THIRD PARTS:

Units from Wolfgang Ehrhardt's crypto and utilities library, are intellectual 
property of Wolfgang Ehrhardt, released uner Zlib license.
The unit FCAES256.PAS is developed with the contribution of both me and, mainly,
of Wolfgang Ehrhardt.

Latest Wolfgang Ehrhardt's libraries used:
aes_2017-11-17.zip
crc_hash_2018-01-01.zip
fca_2017-11-17.zip
serpent_2017-11-17.zip
tf_2017-11-17.zip
util_2018-11-27.zip

7z (LGPL), 7-Zip-zstd codecs (LGPL), Brotli (MIT License), Zstandard (Dual license BSD / GPLv2), ARC (GPL), LPAQ/PAQ8* (GPL), UnACE (royalty free), QUAD (LGPL), BALZ (public domain), strip and UPX (GPL) binaries are needed to support mainstream file formats, they are not included in source package (but are included in the program's precompiled packages) and are intellectual property of respective Authors.

In PeaZip interface are used some icons inspired by Tango Desktop Project, Crystal/Crystal Clear, and NuoveXT, which are originally released under Creative Commons Attribution Share-Alike and LGPL licenses.