How to run your Company Entirely on Open Source Software?

See how three companies successfully run on open source and take this knowledge to your company, department or start-up.

25 Jan 2020 - Frank Bergmann (

Doing consulting work for two customers last year, I noticed two companies that are running mostly on open source. Asking them about their experience, I found striking similarities among them and with my own little company: All three organizations tried to use open source as much as possible, but accepting closed-source, if required by the business.

Open Source Comparison

You can see the result below in a table with the different software products in production use. Some parts of the table are remarkably similar, while differences in other parts seem to reflect the different business areas of the companies.

The article continues with a short presentation of the companies and brief discussion of the various application areas:


cosine builds measurement systems for space and ground based applications. These systems "find use in scientific, industrial, medical, environmental, energy, agri/food, security, semiconductor and space applications, with customers ranging from small high-tech companies to the European Space Agency, IBM and EADS Astrium".

The company employs about 50 researchers, engineers and other specialists and is located near Amsterdam, The Netherlands.

seim & partner

seim & partner is a construction management company specialized in 5G and fiber-optics networks for Germany, but are expanding to the US and Asia. Their customers are local county government or large telecommunications companies. seim & partner manages subcontracting, performs the network planning and supervises the actual civil works on the ground.

They employ about 60 network planners and civil engineers and are located near Frankfurt, Germany.


]po[ is a software company that produces an enterprise project and portfolio management system.

This system is designed for entire companies or departments, rather than smaller work groups. So the focus is on finance and classical PM (a built-in Gantt editor is similar to Microsoft Project), in addition to the usual task-boards etc.

Both cosine, seim & partner and ]po[ itself use ]project-open[ to plan projects, log time sheet hours, check project progress against budget, send invoice to customers, perform financial reporting, manage vacation and a plethora of other tasks.

]po[ has 3 owners, with a lot of work performed in the community and by freelancers.

Desktop - Replacing Windows 10 (or not...)

It struck me that all three companies have decided to use Ubuntu on the "official" desktop OS in order to replace Windows 10. However, all companies have some users running Windows 10, particularly in administration and management.

Other users use Ubuntu as the main system, but use centrally installed Windows via RDP or as a virtual machine on top of Ubuntu. VMware Workstation works very well here including GPU and USB pass-through, while Qemu-KVM and VirtualBox work, but are less user-friendly.

All three companies use LibreOffice/Thunderbird as the main office tools and seem reasonably happy with it. cosine actually prefers Writer over Word. However, all three companies also use Microsoft Office for communication with external parties.

Cloud Use and Server-Side Virtualization

All three companies above use virtualization and cloud somehow different from what is suggested by the media hype around this area.

cosine runs a classical server room for internal servers and uses public cloud services from time to time for resource consuming simulations. Most servers run bare-metal, but some VMware ESXi is in use.

seim & partner keeps its important servers in a colocation site close to it's office and uses LXC containers for the bulk of virtualization.

]project-open[ runs a silent rack in-house for development servers using VMware ESXi. ]po[ itself offers SaaS hosted application cloud services that run on bare metal Linux servers rented from and

Firewall and Security

pfSense and IPFire serve as firewalls to protect the internal services of the three companies and allow VPN access for road warriors and satellite offices.

Authentication, File Sharing and Collaboration

OpenLDAP and Samba are used for LDAP identity management, Samba, Nextcloud and SVN as file-server, NextCloud and Kopano for shared Calendars. GoToMeeting is used by seim & partner and ]po[ for online collaboration, since it allows operation on both Windows and Linux clients. cosine uses Matrix + Riot for messaging.

Project Management, Finance, Accounting & ERP

All three companies in this article run ]project-open[ to cover project management, portfolio management, time sheet, HR, management accounting, invoicing and other ERP functionalities. External tax consultants handle accounting and reporting to tax authorities.

However, this does not mean that ]po[ is the standard application covering these business areas, it is just due to the way this article was written. Other open source application covering this area include Odoo, OpenPSA, Compiere and ADempiere. Application covering project management and time sheet include Redmine, Open Project and many others. SQL-Ledger and it’s forks (LedgerSBM and LX-Office/Kivitendo) provide support for double-entry accounting.

Please note that all three companies in this article are service companies, so their main business is based on projects and knowledge workers logging hours in order to create value. This is similar to IT departments, but is different from retail (Web shops, ...) and manufacturing type of companies which are based on a flow of physical goods and require a classical ERP system to handle this flow and its financial impact.

Why Open Source?

The three companies in this article use open source for very different reasons:

seim & partner opted for open source mainly for security reasons as they operate in network engineering and have been a target of cyber-attacks previously.

]project-open[ is an open source software company, so not using open source actually requires justification.

cosine sees advantages in the possibility to tailor OSS to the needs of the company. Many users seem to be familiar with with open source from their university work.

The ROI of using open source

So, does the use of open source save money? The truth is that it is not that clear and that it seems to depend on the area.

The general perception is that gains in license costs is as least partially offset by more expensive IT staff, but there are no hard numbers available from these three companies.

On the client side the problem is particularly visible, because every issue is multiplied with the number of users. A few additional hours spent on formatting an Impress presentation or debugging a docking station driver may decide for a positive or negative ROI. Ubuntu and LibreOffice have come a long way, but don’t provider the user experience offered by Microsoft or Apple.

The situation seems to be quite different on the server side. My take is that the ROI really depends on the availability of skilled administrators that can tame the open source beasts and the people in the communities around them.

This situation changes completely once security or digital sovereignty concerns appear. Windows 10 "sensor reporting" blatantly violates European GDPR data-protection laws and not everybody may trust Apple, Google or Microsoft to keep their sensitive data safe in an increasingly populist political environment.

About the Author

I am Frank Bergmann , the founder and CEO of ]project-open [. I have spent the last 20 years implementing business software in more than 300 medium to large organizations. You can contact me directly at Please let me know if your company is also moving to open source, so I can add your data to this article.




  Contact Us
  Project Open Business Solutions S.L.

Calle Aprestadora 19, 12o-2a

08902 Hospitalet de Llobregat (Barcelona)


 Tel Europe: +34 609 953 751
 Tel US: +1 415 200 2465