Nextcloud vs Microsoft interoperability: how open source gets it right

Nextcloud vs Microsoft interoperability: A side-by-side look

When it comes to Microsoft interoperability, it might seem that their tools play well with others. But do they really? Or are they just difficult to escape, because of big teams, even bigger money, and a strong market grip because of vendor lock-in?

Vendor lock-in is a carefully engineered strategy strengthened through years of market dominance. But in recent years, we see a clear trend towards privacy and technological independence. As organizations are successfully escaping the golden cage of code, others are considering to follow their lead.

Freedom and control in software depend, among other things, on interoperability: the ability of your tools to work well with others.

  • Can you integrate a wide range of features and apps?
  • Does the system support open standards and protocols?
  • Can you build your ideal stack without vendor lock-in?

If those aspects are key factors for you when choosing your collaboration software, you are in the right place. Because Microsoft is not the only feature-rich cloud platform out there. With open source solutions such as Nextcloud, you could get out of your current vendor lock-in and enjoy what matters most: data control and transparency.

Want to get the full story?

Discover more about how the Nextcloud ecosystem compares with Microsoft in our Microsoft 365 mini-series:

Where it all begins: open source vs proprietary code

Let’s start with something that defines all of the aspects of interoperability we are going to talk about: the source code.

How open standards contribute to interoperability

Open source projects push forward open standards, including ActivityPub, OpenAPI, and WebDAV, which allow systems to communicate easily in a unified way and to be built into custom setups regardless of the vendors and platforms.

With access to the source code and the public APIs, any developer can look into how a system works internally and adapt the software they are creating to how it operates. For example, you can take the source code of Nextcloud Deck, build a new app on top of that to extend its features, or build an extension that connects to your other app, or even fork the entire code to do something else. This lowers the barrier of entry for app developers to join the Nextcloud ecosystem.

Open source code greatly expands freedom of choice for software users and an opportunity for the developers: if a component, such as a project management application integrated in a platform, does not satisfy a big portion of users, there’s a demand — and an unlimited possibility — to create or integrate an alternative.

How open standards push collaboration

Open source also fosters collaboration. Organizations and communities may create shared libraries or middleware that improve compatibility across tools they are using. Projects can easily reuse open source modules or libraries that implement certain protocols or data formats. This reduces inconsistency and enhances plug-and-play integration as needed.

Real-world example? The German state of Schleswig-Holstein states in its official “Open Innovation and Open Source Strategy” that they not only publish source code for their specialized administrative applications, but also provide a platform for collaboration and publication of software. This enables other public sector organizations to create and adapt tested and trusted open source software for their needs.

Open source vs proprietary: Microsoft 365 and Nextcloud

Microsoft 365 is closed-source, proprietary software. Their business model relies on vendor lock-in to extract increasing profits from their customer base. Their API’s are designed to increase the value of their ecosystem while not reducing vendor lock-in, for example, giving the ability to add or read metadata in a limited way that makes it hard or impossible to extract data. If you want to integrate applications that compete with core functionality in 365, you quickly discover that API’s are simply missing, or that access is restricted by rate limits, licences or T&Cs.

Nextcloud, on the contrary, is built entirely on open source standards and with open source code, offering freedom by design. Data is stored in industry standard formats and databases. You can easily migrate your data from one location or provider to another, free from vendor lock-in. You can build, integrate and replace any apps and components. And you can learn from best practices and real-world Nextcloud implementations to create a unique, reliable platform for your use case.

The ecosystems: APIs, app development and app marketplace

Now let’s move from the conceptual differences to a more hands-on issue that many administrators deal with.

The ecosystems and its offerings often define the choice of software for a business or public organization. It is about the availability of apps an organization can use. It is also about the ability to integrate other applications already in use in their environment. As most organizations, you might want to keep your mail server or user directory. And of course the apps and data formats their external partners, contractors and other stakeholders use.

Nextcloud interoperability versus Microsoft interoperability: the app stores

Microsoft 365 has strong third-party app support with a large marketplace ecosystem. It offers thousands of plug-and-play integrations for productivity, HR, CRM, finance, and more. You can easily integrate popular tools like Asana, Trello, Zoom, GitHub, Jira, Adobe Sign, ServiceNow, etc. But while Microsoft’s marketplace is very large, it’s also heavily curated and controlled.

Some of the native plug-and-play apps in Microsoft 365 don’t have an exact match in Nextcloud ecosystem. But it provides freedom of integration and development. In case a complete match of functionality is needed, you can integrate an external service. Plenty of such integrations are available, with sometimes even several tools to choose from. For example, you can integrate Saber as a OneNote alternative, or use Dovecot or Stalwart as your mail server as an alternative to Microsoft Exchange.

Microsoft interoperability? Control through API

Let’s discover what the APIs and the ecosystem allow, and how Microsoft controls its ecosystem’s interoperatbility through API.

Microsoft 365 remains a closed system where extensibility is limited to what the vendor permits: through Microsoft’s Graph API and Power Platform. For example, some of the Graph API’s endpoints are restricted to specific licenses, such as E5, and some APIs apply usage-based charges.

Microsoft limit the features of their API to control your (their) ecosystem, instead of letting you control what you are using. They have no interest in enabling other products to compete with their own, so licensing and APIs are generall in favor of Microsoft-native tooling over alternatives.

For example, Microsoft prohibits using APIs to migrate customers away from Microsoft offerings, or to reverse-engineer data access, with Microsoft reserving the right to modify or discontinue APIs at any time.

Nextcloud operates fully on open standards, letting the data remain interoperable and supporting easy migration between solutions, ultimately allowing you to swap applications, connect and build your own without API-implied restrictions.

Some of the open standards used in Nextcloud apps include:

  • OCM / Federated Sharing API. Used for federated sharing and other federation features (calls, chats) between Nextcloud servers.
  • OpenAPI & standardized RESTful endpoints. Nextcloud uses OpenAPI definitions and standard RESTful APIs for many of its services, allowing third-party integrations and automation tools (like Zapier or n8n) to plug in easily. Microsoft supports some of those through Microsoft Graph, which is proprietary, complex, and changes frequently.
  • WebDAV. Nextcloud fully supports this standard and lets you to mount your Nextcloud storage as a network drive on almost any OS. 
  • CalDAV, CardDAV for processing calendars and contacts. Microsoft deprecated these standards in favor of Microsoft Graph and proprietary APIs.
  • ActivityPub, a federated social networking protocol. Nextcloud uses it to enable federated sharing and notifications from social platforms (e.g. Mastodon, PeerTube) and other Nextcloud instances.

In other words, Nextcloud’s app store is open source by default, with unlimited possibilities to create your own environment. If an app doesn’t exist, you build it. Or if it doesn’t suit you, you can fork it for extensibility and autonomy.

User management: does everyone belong?

Another important interoperability aspect lies in the user directory.

Microsoft 365’s user management framework is based entirely on Azure Active Directory where user provisioning is done through Azure AD portal or Graph API and is tied to licensing. What’s more, guest access always requires creation of Microsoft or linked account without external identity support.

Nextcloud does not have or does not aim to have own user directory. Instead, it is very flexible in its user identity framework: You can use any identity provider — from classic LDAP to Google, GitHub, or a local database. This makes Nextcloud portable across infrastructures. Nextcloud can support connections to Active Directory (AD), including Microsoft’s AzureAD, LDAP, SSO & SAML connections.

You can work between federated Nextcloud instances using the same account from your instance, which works via Federated Cloud Sharing API. Or let users log in with existing credentials via SAML/OIDC without forcing them into a new identity framework.

In Nextcloud, users and their metadata can be exported, migrated, or synced through open protocols, giving you true data sovereignty and freedom of interoperability.

Nextcloud vs Microsoft interoperability: the verdict

Find a summary of our detailed findings for this comparison between Microsoft 365 and Nextcloud in a more compact format:

Microsoft 365Nextcloud
Open source vs proprietary codeMicrosoft’s proprietary code keeps users and developers dependent on its rules and roadmap.Nextcloud’s open source model gives full control, transparency, and adaptability
Support for open standardsPrefers “talk to Microsoft” philosophy: Microsoft often wraps interactions in its own standards, locking communication within its ecosystem.Embraces the “talk to anyone” philosophy: Nextcloud is built on open protocols that ensure interoperability across platforms, easy migration and transfer of data.
Ecosystem: APIs, app development & marketplaceProvides powerful tools, but mostly within the confines of Graph, Azure, and tightly licensed SDKs.Nextcloud’s ecosystem encourages lightweight, transparent integration via open APIs and a community-driven app store.
Identity managementCentralizes identity through Azure AD, often creating friction when dealing with external users or non-Microsoft systems.Supports a wide range of authentication methods (LDAP, SAML, OAuth2), enabling true integration into diverse IT environments.

In this article, we focused on the key related topics for interoperability, such open standards, open code, the API and user management. But we’d love to talk more about the topic, such as maintenance and usage of both platforms, as well as migration.

Ready to discuss and expand upon the questions of interoperability? Share your thoughts in comments on the forum!

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