C++ / Backend Engineer

Luxoft Poland; Polska; On-site; PLN 120,000 - 180,000; Part time

Job summary

Luxoft Poland seeks an experienced C++ / backend engineer for a short-term engagement to lead refactoring and modernization of a large cross-platform desktop application built with Qt5. Your primary focus will be migrating the macOS build from Intel to Apple Silicon, updating Conan workflows, and upgrading the Linux build to Clang 19 on Ubuntu 24.04, while moving the codebase to C++20.

You'll work with a mature codebase (~500k LOC) and collaborate across Windows, macOS, and Linux environments,

Qualifications

• Proficiency in modern C++ (C++17/20) and cross-platform development.
• Strong experience with CMake and build-system configuration.
• Hands-on knowledge of Conan package manager.
• Familiarity with the Clang/LLVM toolchain.
• Experience with Qt5 application development and macOS packaging/code signing.
• Experience with Docker-based CI/CD pipelines and large legacy codebases.

Responsibilities

• Migrate the macOS build of the application from an Intel to an Apple Silicon build (C++ codebase, ~500k LOC plus third-party libraries, Qt5).
• Migrate third-party libraries from Conan 1.x to Conan 2 across the Windows, macOS, and Linux builds.
• Update the Linux build to use Clang 19 (from Clang 11) and move the build to Ubuntu 24.04.
• Update selected third-party libraries to recent versions to meet security requirements.
• Migrate the codebase from C++17 to C++20.

Skills

Modern C++ (C++17/20)

Cross-platform development

CMake

Conan package manager

Clang/LLVM toolchain

Qt5 development

macOS packaging/code signing

Docker-based CI/CD

Tools

Conan

CMake

Qt5

Clang

Docker

Job description

We are looking for an experienced C++ / backend engineer to join on a short-term, time-bound basis to lead refactoring and modernization work on a mature desktop application. The product has a large, cross-platform C++ codebase (~500k lines of code plus third-party dependencies) built on Qt5. The primary goal of the engagement is to modernize the build toolchain and dependency stack, with the migration to Apple Silicon as the top priority.

Not all of the tasks below are guaranteed to be completed within the engagement. At a minimum, the Intel → Apple Silicon migration must be delivered; remaining items will be prioritized based on time and progress.

Responsibilities

• Migrate the macOS build of the application from an Intel to an Apple Silicon build (C++ codebase, ~500k LOC plus third-party libraries, Qt5).
• Migrate third-party libraries from Conan 1.x to Conan 2 across the Windows, macOS, and Linux builds.
• Update the Linux build to use Clang 19 (from Clang 11) and move the build to Ubuntu 24.04.
• Update selected third-party libraries to recent versions to meet security requirements.
• Migrate the codebase from C++17 to C++20.

Skills

Must have

• Proficiency in modern C++ (17/20) and cross-platform development across Windows, macOS, and Linux.
• Strong experience with CMake and build-system toolchain configuration.
• Hands-on knowledge of the Conan package manager.
• Familiarity with the Clang / LLVM toolchain.
• Experience with Qt5 application development and macOS packaging / code signing.
• Comfortable working with Docker-based CI/CD pipelines and large legacy codebases.

Nice to have

• Prior experience migrating desktop applications to Apple Silicon.