Case Study 2: Five Real-World Pascal Applications

A survey of significant software built with Pascal and Delphi, demonstrating the language's range and endurance.

Overview

When people claim that Pascal is a "dead language," they are making an empirical claim — one that can be tested against evidence. This case study examines five real-world applications built with Pascal or Delphi, each significant in its domain, each still in active use. Together, they demonstrate that Pascal is not merely surviving as a curiosity but thriving as a tool for building software that millions of people use every day.

1. Total Commander — The File Manager That Refused to Die

Developer: Christian Ghisler (one person) Language: Delphi First release: 1993 (as Windows Commander, renamed 2002) Status: Actively developed (version 11.x as of 2026) Users: Millions worldwide, especially popular in Central and Eastern Europe

The Story

Christian Ghisler wrote the first version of Total Commander (then called Windows Commander) in 1993 as a Norton Commander clone for Windows 3.1. He chose Pascal — initially Turbo Pascal for Windows, later migrating to Delphi — because he knew the language well and it produced fast, small executables.

Thirty-three years later, Ghisler is still developing Total Commander, still in Delphi, still as a one-person operation. The application has grown from a simple two-panel file manager into a comprehensive file management tool with built-in FTP/SFTP, archive handling (ZIP, RAR, 7z, and dozens of other formats), file comparison, batch renaming, multi-rename tool, and a plugin ecosystem with over 200 third-party plugins.

Why It Matters

Total Commander demonstrates that a single developer, using Pascal, can build and maintain a commercial application for over three decades. The application's code has evolved from 16-bit Windows 3.1 to 64-bit Windows 11 without a rewrite — a testament to both the developer's skill and Delphi's backward compatibility. The application remains fast (it starts in under a second on any modern hardware) because it is natively compiled Pascal, not an Electron wrapper around a web browser.

Technical Highlights

  • Plugin architecture using DLLs with a well-defined Pascal interface.
  • Multi-threaded file operations (copy, move, delete) with progress reporting.
  • Custom-rendered file list with column-based sorting and inline editing.
  • FTP/SFTP client with resume support and TLS encryption.

2. FL Studio — The Music Production Tool Used by Grammy Winners

Developer: Image-Line (Belgium) Language: Delphi (core engine and UI) First release: 1997 (as FruityLoops) Status: Actively developed (version 24.x as of 2026) Users: Millions; professional users include Avicii, Martin Garrix, Metro Boomin, and many other producers

The Story

FL Studio began as FruityLoops, a simple drum machine application created by Didier Dambrin (known online as "gol") at Image-Line in Belgium. Written in Delphi, it was initially a straightforward step sequencer for creating drum patterns.

Over the years, FL Studio evolved into one of the most popular digital audio workstations (DAWs) in the world. It now includes a full mixer, piano roll editor, automation, audio recording, video synchronization, and support for thousands of third-party plugins (VST, VST3, AU). It has been used to produce chart-topping hits across hip-hop, electronic, and pop music.

Why It Matters

FL Studio is perhaps the most powerful argument against the claim that Pascal cannot build "real" software. A DAW is one of the most technically demanding application types: it must process audio in real-time (latency-critical), render complex GUIs with smooth animations, manage hundreds of plugin instances simultaneously, and remain stable during hours-long creative sessions where a crash means lost work.

FL Studio does all of this in Delphi-compiled native code. The real-time audio engine processes samples at the driver level with latency measured in milliseconds. The custom-rendered UI (not standard Windows controls) provides the smooth, responsive experience that music producers require.

Technical Highlights

  • Real-time audio processing with ASIO driver support (sub-10ms latency).
  • Custom GUI rendering engine (not VCL controls) for the mixer, piano roll, and plugin windows.
  • Plugin hosting: loads and manages hundreds of VST/VST3 plugins in separate processes.
  • Undo/redo system that can track thousands of operations.
  • Project files that can reference gigabytes of audio samples and remain responsive.

3. Double Commander — Cross-Platform File Management

Developer: Community (originally Alexander Koblov) Language: Free Pascal + Lazarus First release: 2008 Status: Actively developed (version 1.1.x as of 2026) License: GPL v2 Platforms: Windows, Linux, macOS, FreeBSD

The Story

Double Commander is an open-source, cross-platform file manager inspired by Total Commander. It is built entirely with Free Pascal and Lazarus, using the LCL for its cross-platform GUI. The project demonstrates that the Free Pascal + Lazarus combination can produce a polished, feature-rich desktop application that runs on every major platform.

Why It Matters

Double Commander is significant for the Free Pascal ecosystem because it is one of the most visible, most-downloaded applications built with Lazarus. It appears in Linux distribution repositories (apt, dnf, pacman), which means millions of Linux users have easy access to a Lazarus-built application. Every time a Linux user installs Double Commander, they are implicitly validating the Free Pascal ecosystem.

The project also demonstrates Lazarus's cross-platform capabilities. The same codebase compiles for Windows (using Win32 widgetset), Linux (using GTK2 or Qt5), macOS (using Cocoa), and FreeBSD. The application looks native on each platform because the LCL uses native widgets.

Technical Highlights

  • Dual-panel file manager with tabbed browsing.
  • Built-in archive handling (ZIP, TAR, GZ, BZ2, XZ, 7z, RAR).
  • Internal text and hex editors.
  • Multi-rename tool with regular expression support.
  • WCX, WDX, WFX, and WLX plugin support (compatible with Total Commander plugins).
  • Over 100 contributors on GitHub.

4. HeidiSQL — The Database Management Tool

Developer: Ansgar Becker (originally, now community-maintained) Language: Delphi First release: 2006 (as MySQL-Front, later renamed) Status: Actively developed License: GPL v2 Users: Popular tool for MySQL, MariaDB, PostgreSQL, and MSSQL management

The Story

HeidiSQL is a free, open-source database management tool for Windows. It connects to MySQL, MariaDB, PostgreSQL, Microsoft SQL Server, and SQLite, providing a graphical interface for browsing databases, writing queries, managing tables, importing/exporting data, and administering users.

Written in Delphi and released under the GPL, HeidiSQL demonstrates that Delphi code can be open-source. The project's repository is on GitHub, and it accepts community contributions.

Why It Matters

HeidiSQL is installed on millions of developer machines. When a web developer sets up a local development environment with MySQL or MariaDB, HeidiSQL is one of the most commonly recommended management tools. Many of these developers have no idea they are using a Delphi application — it simply works, starts quickly, and handles large databases without the sluggishness that characterizes some Electron-based alternatives.

Technical Highlights

  • Virtual tree for database/table navigation (handles thousands of tables without slowdown).
  • Query editor with syntax highlighting, auto-completion, and query history.
  • Visual query builder for JOIN operations.
  • Data export to CSV, SQL, XML, HTML, and other formats.
  • SSH tunnel support for secure remote database connections.
  • Handles databases with millions of rows (virtual-mode grid loads on demand).

5. PeaZip — Cross-Platform File Archiver

Developer: Giorgio Tani Language: Free Pascal + Lazarus First release: 2006 Status: Actively developed (version 9.x as of 2026) License: LGPL v3 Platforms: Windows, Linux Downloads: Over 90 million (as reported on SourceForge)

The Story

PeaZip is a free, open-source file archiver and compression tool that supports over 200 archive formats. It provides a graphical interface for creating, opening, and extracting archives, with features including encryption, file splitting, checksum verification, and batch extraction.

Written in Free Pascal with a Lazarus GUI, PeaZip is one of the most-downloaded Free Pascal applications in existence. Its SourceForge page reports over 90 million downloads, making it a major success story for the Free Pascal ecosystem.

Why It Matters

PeaZip demonstrates that Free Pascal applications can achieve massive adoption. Ninety million downloads puts PeaZip in the same league as well-known open-source tools like 7-Zip, VLC, and GIMP. The application competes directly with tools written in C and C++, and users who download it encounter no difference in performance, stability, or capabilities.

Technical Highlights

  • Support for 200+ archive formats via integration with 7z, Brotli, Zstandard, and other backends.
  • Secure deletion (overwrite before delete).
  • File hashing and checksum verification (CRC32, MD5, SHA-256, SHA-512, BLAKE2).
  • Password manager for archive encryption keys.
  • Portable version (no installation required, runs from USB drive).
  • Clean, modern UI built with the Lazarus LCL.

Patterns Across All Five

Several patterns emerge from these five applications:

  1. Longevity. All five applications have been actively maintained for over fifteen years. Total Commander has been maintained for over thirty. Pascal applications do not have shelf lives — they have lifespans.

  2. Performance. Every application starts fast, runs fast, and handles large datasets without the memory bloat that characterizes applications built on interpreted or managed runtimes. This is native compilation at work.

  3. Small teams. Total Commander is maintained by one person. PeaZip is primarily one person. FL Studio's core team is small. Pascal's simplicity and the efficiency of the Delphi/Lazarus RAD tools make small-team development viable for complex applications.

  4. Real users. These are not academic exercises or portfolio projects. They are tools used by millions of people to do real work — manage files, produce music, administer databases, compress archives. The users do not care what language the software was written in. They care that it works.

  5. Cross-platform potential. Double Commander and PeaZip demonstrate that the same Free Pascal/Lazarus codebase compiles for Windows, Linux, and macOS. Total Commander and FL Studio are Windows-only by choice (their markets are Windows-focused), not by limitation.

The next time someone tells you that Pascal is dead, you can point to these five applications and ask: does "dead" software get ninety million downloads?