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Every year, European companies discover that their proprietary‑software vendor is raising its fees by 15 to 30 percent, with no real room for negotiation. The invoice swells, the data remain captive, and technical flexibility shrinks. Why is open source better than proprietary software? Faced with this central question, Open Source emerges as a credible alternative to proprietary platforms, backed by active communities, mature business models, and a growing demand for digital sovereignty. Far from being a simple ideological choice, the use of Open‑Source software addresses concrete issues of cost, security, independence and agility. Organisations that explore it are not looking for a cheap substitute: they want to regain control over their IT infrastructure, their data and their capacity to innovate. This shift does not happen without friction, but the measurable benefits explain why the share of open source in information systems continuously grows, even in heavily regulated sectors such as banking or health care.
The emergence of Open Source against proprietary hegemony
Limits and risks of closed ecosystems
Proprietary platforms operate on a simple principle: the source code remains the exclusive property of the vendor. The user purchases a right of use, not a right to view or modify. This model creates structural dependency. When Microsoft decides to remove a SharePoint feature or when Salesforce changes its APIs, client companies have no choice but to adapt, often urgently and at their own expense.
Vendor lock‑in is the most documented risk. Migrating from Oracle Database to another DBMS after ten years of use involves redesign costs that run into hundreds of thousands of euros for a mid‑size enterprise. Proprietary data formats, specific connectors and non‑standard extensions create a mesh that is costly to extract from. The global outage of CrowdStrike in July 2024, which crippled 8.5 million Windows machines, also reminded everyone of the fragility of an excessive reliance on a single supplier for critical components.
Fundamental principles of software freedom
The Free Software Foundation defines four essential freedoms:
- Run the program for any purpose;
- Study how it works and adapt it;
- Redistribute copies; and improve the program;
- Publish the improvements.
These principles, formalised by Richard Stallman in the 1980s, distinguish free software from mere freeware.
Open‑source licences (GPL, Apache 2.0, MIT, EUPL) legally frame these freedoms. The GPL requires that any derivative work remains free, whereas the MIT licence permits integration into proprietary code. This legal framework is not a trivial detail: it determines what a company can actually do with the software. The Open Source Initiative (OSI) maintains an approved licence list that serves as a reference for legal departments.
Digital sovereignty and data control
Independence from the GAFAM
The issue of digital sovereignty has taken on a political dimension in Europe since the invalidation of the Privacy Shield in 2020 (Schrems II decision). Companies and public administrations that store personal data on US platforms expose themselves to a real legal risk, because the Cloud Act allows US authorities to access data hosted by American‑registered companies, even when the servers are located in Europe.
Open source offers a concrete exit route. Solutions such as Twake Workplace (secure collaboration and communication), Matrix/Element (messaging) or OpenStack (cloud infrastructure) enable the deployment of services equivalent to Google Workspace or AWS on internally controlled infrastructure. Twake Workplace, in particular, provides a complete sovereign alternative that integrates messaging, document sharing and collaborative tools in a unified open‑source environment. The French Direction Interministerielle du Numérique (DINUM) explicitly recommends the use of free software in administration, maintaining a regularly updated Interministerial Base of Free Software (SILL). Germany, through the Sovereign Cloud Stack project, pursues the same logic at the federal level.
Code transparency and security auditability
A common argument against Open Source is that making the code visible could aid attackers. The reality is more nuanced. Linus’s Law (“given enough eyeballs, all bugs are shallow”) holds for well‑maintained projects. The Linux kernel, with thousands of contributors, patches critical vulnerabilities within days, sometimes hours. The Log4Shell flaw (CVE‑2021‑44228) was patched in Apache Log4j in less than 72 hours after public disclosure.
Source‑code auditability also lets companies commission their own teams or independent providers to verify the absence of backdoors. The French ANSSI (National Cybersecurity Agency) encourages this practice and publishes hardening guides for free software such as OpenSSL or OpenSSH. The main difference between open source and proprietary software lies in this transparency, which simply does not exist with proprietary products where users must trust the vendor without independent verification.
Economic advantages and agility for businesses
Reduction of licence costs and vendor lock‑in
The absence of licence fees does not mean the absence of costs. Open source shifts the expense: fewer licences, more services (integration, training, support). A 2021 study by the European Commission estimates that EU companies investing in open source generate an economic return of 1 to 4 in terms of GDP impact. Total Cost of Ownership (TCO) calculations must include hosting, maintenance, skill development and vendor or community support.
The decisive factor remains reversibility. With PostgreSQL, a company can change hosting providers or service partners without losing data or rewriting SQL queries. Open formats (ODF for office, S3‑compatible for object storage) guarantee portability. This flexibility translates into increased negotiating power with suppliers, because the exit cost is low.
Collaborative innovation and development speed
The collaborative development model accelerates innovation cycles. Kubernetes, born at Google in 2014, became in less than ten years the standard for container orchestration, backed by the Cloud Native Computing Foundation and hundreds of contributing companies. No proprietary vendor could have built such an ecosystem alone.
Companies that contribute to open‑source projects reap direct benefits: they influence the roadmap, attract skilled developers and reduce technical debt by relying on components maintained by a broad community. Red Hat, Canonical, GitLab and Grafana Labs have built profitable business models around this logic, offering commercial support, enterprise features and managed services on top of a free core.
Overview of free alternatives by sector
Office productivity and collaboration tools
The desktop is often the first migration target. LibreOffice replaces Microsoft Office for word processing, spreadsheets and presentations, with reasonable compatibility for .docx and .xlsx files. For email and calendar, solutions such as Thunderbird combined with a Zimbra or SOGo server meet standard needs.
Collaboration alternatives have expanded considerably:
- Nextcloud - file sharing, collaborative editing, video‑conference (Talk), project management (Deck)
- Mattermost or Rocket.Chat - team instant messaging, comparable to Slack
- Jitsi Meet - video‑conference, deployable on an internal server in under an hour
- OnlyOffice - online office suite integrated with Nextcloud, faithful rendering of Microsoft documents
- Twake‑Workplace - all‑in‑one digital suite for enhanced confidentiality
The French National Gendarmerie has used LibreOffice on 80 000 workstations since 2014, frequently cited as proof of large‑scale viability.
Cloud infrastructure and database management
For infrastructure, OpenStack and Proxmox VE provide alternatives to proprietary hypervisors such as VMware, whose acquisition by Broadcom triggered a sharp price hike in 2024. Proxmox, built on KVM and LXC, attracts SMEs and hosting providers thanks to its ease of administration and licence‑free per‑socket model.
In the database arena, PostgreSQL dominates the open‑source relational segment, offering features (partitioning, logical replication, extensions like PostGIS or TimescaleDB) that rival Oracle or SQL Server. MariaDB, a fork of MySQL, remains widely used for web applications. For NoSQL, MongoDB Community Edition and Redis cover most use cases, although MongoDB has switched to the SSPL licence to limit cloud‑provider exploitation.
Adoption challenges and model sustainability
Implementation complexity and technical support
Migrating to open source requires internal competence or strong external assistance. Deploying a production Kubernetes cluster, for instance, demands mastery of networking, distributed storage and container security, skills not present in every team. The lack of “turn‑key” telephone support can deter IT directors accustomed to the classic vendor model.
Project maturity varies considerably. The Linux kernel benefits from a dense commercial support ecosystem (Red Hat, SUSE, Canonical). Other, newer or niche projects depend on a few volunteer maintainers, raising sustainability concerns. The xz Utils incident (CVE‑2024‑3094), where a malicious contributor attempted to insert a backdoor into a compression utility used by almost every Linux distribution, highlighted the fragility of certain supply‑chain links.
Towards a hybrid and responsible future
In practice, the landscape is rarely binary. Most organisations adopt a hybrid model, mixing open‑source blocks with proprietary services where appropriate. A hospital might run PostgreSQL for its core information system while retaining a certified proprietary medical application. The goal is not to replace 100 % of the software estate, but to make informed, piece‑by‑piece decisions.
European regulation nudges in this direction. The Cyber Resilience Act imposes security requirements on all software products, including open source, which should strengthen professional maintenance of critical projects. The EU’s NGI (Next Generation Internet) programme directly funds strategic free‑software initiatives. Open source is therefore not an end in itself; it is a lever to build more resilient, transparent and less vendor‑dependent information systems. organisations that invest today in this direction give themselves the means to stay masters of their digital trajectory.
