Who is responsible for updates after delivery?

Oscar Bout · 30 Aug 2026

Responsibility for post-delivery updates lies with the party that has contractually established this. Without clear agreements, the client generally bears responsibility themselves once the software has been delivered and approved. Below, we answer the most frequently asked questions on this topic, so you know exactly where you stand.

What exactly falls under ‘post-delivery updates’?

Post-delivery updates are all changes, improvements, and maintenance activities that take place after the software has been officially delivered and approved. This includes both technical and functional adjustments needed to keep the software running correctly and securely.

Specifically, the following fall under post-delivery updates:

Bug fixes: resolving errors that come to light after delivery
Security updates: patches that address vulnerabilities in the software or libraries used
Compatibility updates: adjustments required because external systems, browsers, or operating systems have changed
Functional enhancements: new features or requests that arise after delivery
Performance improvements: optimizations that improve speed or stability

The distinction between a bug that already existed before delivery and a problem that only arises later is important here. That boundary determines who is responsible for resolving it.

What does a delivery contract normally say about maintenance?

Most delivery contracts for software development include a warranty period of 30 to 90 days after delivery. Within that period, the developer is responsible for resolving errors that directly result from the delivered work. After that period, that obligation lapses, unless additional agreements have been made.

What you often do find in a standard contract:

A warranty clause for defects that were demonstrably present at the time of delivery
A description of what delivery entails and when it is formally completed
Exclusions for problems arising from the use of third-party software or changes made by the client themselves

What you do not automatically find in it is an obligation for ongoing maintenance. That requires a separate maintenance contract. Without such a contract, the developer is not obligated to carry out updates after the warranty period, even if security vulnerabilities emerge.

When does responsibility lie with the developer?

Responsibility for updates lies with the developer when this has been contractually established, or when it concerns defects that were already present at the time of delivery. A developer is obligated to fix errors that are the direct result of their own work, as long as the warranty period is running.

Outside the warranty period, the developer is responsible in the following situations:

An active maintenance contract has been signed that covers maintenance and updates
The client has demonstrated that a problem already existed before the formal delivery
Additional written agreements have been made regarding ongoing support

Note: if you as the client have made changes to the code or the environment after delivery, the developer’s liability generally lapses for problems that arise thereafter. This is a common pitfall in software development projects.

When is the client themselves responsible for updates?

The client is themselves responsible for updates once the warranty period has expired and there is no maintenance contract. From that point on, the software is fully owned by the client, including all associated responsibilities for management, security, and further development.

In practice, this means that as a client you must take care of:

Keeping security updates current for frameworks and libraries used
Testing and implementing compatibility updates when changes occur in the environment
Hiring a developer or team for new functionalities
Monitoring the technical quality of the software in the long term

This is precisely why it is wise to think about how you will manage the software after delivery even before the delivery takes place. Who keeps the servers up to date? Who implements updates? Who is available if something goes wrong? Without answers to those questions, you are running unnecessary risks.

What is a maintenance contract and when do you need one?

A maintenance contract is a separate agreement between the client and the developer that establishes which activities the developer will continue to carry out after delivery, under what conditions, and at what rate. It therefore goes beyond the standard warranty in a delivery contract.

You need a maintenance contract when:

The software is actively used and downtime or security issues have direct consequences for your business
You expect the software to need regular adjustments or expansions
You do not have the internal technical knowledge to assess or implement updates yourself
The software depends on external APIs, frameworks, or platforms that are regularly updated

A maintenance contract provides certainty and prevents you from having to renegotiate rates and priorities every time a small problem arises. For businesses that depend on their software as part of their core process, a maintenance contract is a wise investment.

How do you make clear agreements about updates before delivery?

You make clear agreements about updates by explicitly including this topic in the contract before the project begins. Do not wait until delivery to discuss this. Bring it up during the quotation phase and record it in writing in the agreement.

Make sure the following points are concretely described:

The length and content of the warranty period: what is and is not covered?
The definition of ‘delivery’: when has the software been officially accepted?
Who is responsible for external dependencies such as libraries, frameworks, and APIs
Whether a maintenance contract is available and what its terms are
How future changes are requested and priced

The more specific the agreements, the less room there is for misunderstandings afterward. A good software development partner actively helps you draw up these agreements, rather than leaving them vague.

How 3Bird helps with clear agreements and maintenance after delivery

At 3Bird, we believe that a good collaboration starts with transparency, including about what happens after delivery. We guide you not only during development, but also help you make the right agreements about management and maintenance.

What we concretely offer:

Clear contracts with explicit warranty provisions and delivery criteria
Flexible maintenance agreements tailored to your situation and budget
Guidance from Dutch fractional CTOs who speak your language and think ahead about the long term
Access to a team of 30 experienced developers who can scale up quickly when needed
Rates from €25 per hour, so that ongoing maintenance remains financially feasible

Whether you want to start a new software project or are looking for support with an existing application, we are happy to think along with you. Get in touch via +(31)75-7993038 or send an email to contact@3bird.nl for a no-obligation conversation.