Custom iWmo and iJw integration development
Appfront builds custom integrations with the iWmo and iJw standards, so that the messaging between municipalities and care providers runs fully automated through your own administration. Assignments, start and stop notifications and declarations are validated, processed and reported back, via the Municipal Data Hub (GGK) and VECOZO. Less manual work, fewer errors, and a chain that demonstrably conforms to the official iStandards.
What are iWmo and iJw?
iWmo and iJw are the iStandards for electronic messaging in the social domain. iWmo governs the data exchange around support under the Social Support Act (Wmo), while iJw governs youth care under the Youth Act (Jeugdwet). They are maintained by Zorginstituut Nederland and ensure that municipalities and care providers exchange information in a standardised way, from assignment through to care delivery and declaration.
Messaging takes place through structured messages with fixed numbers: the municipality sends an assignment (301), the provider confirms (302), reports the start of care with a start notification (305), the end with a stop notification (307), and declares periodically with a declaration message (323). Every message has a response message. On the municipal side, transport runs via the Municipal Data Hub (GGK) of the Inlichtingenbureau, and on the provider side via VECOZO.
Appfront builds the integration according to the official iStandards specifications and the OWASP ASVS security standard. We align message validation, response processing and error handling with your actual workflows, so that the integration keeps pace with the annual releases of iWmo and iJw and messaging remains reliable even at peak volumes.
Assignment and response
The municipality grants care or support with a 301 assignment; the provider confirms with a 302 response message. Your administration processes both automatically and keeps the assignment and the client record in sync without manual re-entry.
Start and stop messages
With a start notification (305), the provider reports the start of care; with a stop notification (307), the end. The integration sends these automatically at the right moment and processes the corresponding response messages (306 and 308) back into your planning.
Claims and invoicing
The care delivered is declared periodically with a 323 declaration message; the municipality reports approval or rejection per line back with a 325 response message. The older 303 and 304 messages have been retired since iWmo 3.1, so we build on the current standard.
This page is about the transport of messages. For what you need on the side where return messages and rejections are handled and investigated, see software for iJw message traffic and accountability.
Our development process for iWmo and iJw integrations
We work with a proven method that removes uncertainty early and delivers a stable integration. From an initial analysis of your role in the chain, the message flows you need and the connection to the GGK or VECOZO, through to go-live and ongoing maintenance — every step is aimed at an integration your team can understand and trust.
We map whether you use iWmo, iJw or both, which messages you want to process (assignment, start, stop, claim), what role you play in the chain and which node you connect to.
We design the integration architecture, arrange the connection with PKIoverheid certificates and draw up a strategy for validation and error handling of return messages.
Implementation with automated tests against the iStandaarden specification, structured logging and monitoring. You see working builds along the way.
Controlled go-live with message validation and a safety net, followed by ongoing management and delivery alongside new iWmo and iJw releases.
What an iWmo and iJw integration delivers in practice
Every integration is set up specifically for your role in the chain, the message flows you need and your existing administration. Below are the features we most often deliver for municipalities, care providers and software vendors in the social domain.
Assignment processing (301/302)
Incoming allocations (301) are read in automatically into your care or municipal administration and linked to the correct client record. The response message (302) is generated and sent automatically, validated against the current iWmo or iJw specification.
Request for assignment (315/316)
For delivery variants in which the provider itself requests an allocation: the allocation request (315) is generated from your system, and the municipality responds with a response message (316). Change requests (317/318) are also supported.
Start and stop of care (305/307)
Start messages (305) and end messages (307) are generated and sent automatically based on your schedule, with processing of the response messages 306 and 308. This keeps the care status in your administration in sync with the municipality's.
Claim processing (323/325)
Claims (323) are compiled from the recorded care delivered and sent periodically. The return claim (325) is processed per line — approved, rejected or under review — so your financial administration knows the status of every claim line.
GGK and VECOZO connection
The integration connects to the right node: the Municipal Data Node (GGK) of the Inlichtingenbureau on the municipality side, or VECOZO on the provider side. We handle the technical connection, the certificates and the processing over Digikoppeling.
Validation, logging and monitoring
Every incoming and outgoing message is validated against the iStandaarden specification and fully logged. A dashboard shows outstanding response messages, rejected declaration lines and processing errors, so your administration can see discrepancies straight away and follow them up.
Typical use cases in practice
An iWmo and iJw integration works out differently for each organisation, depending on your role in the chain. We see a number of contexts come up often — and for each of them we have a suitable set-up, with attention to the right message flows, node connection and return processing.
Municipalities
Municipalities that want to connect their Wmo and youth administration to the GGK, so that allocations, start and stop messages and declaration responses are handled automatically. We connect to your existing system or build custom software. See also our software for municipalities and our Digikoppeling integration.
Care providers
Wmo and youth care providers that want to process message traffic directly in their own care administration instead of manually in the VECOZO portal. Allocations, start and stop messages and declarations flow through automatically, with response messages fed straight back.
Social domain software vendors
Care and municipal software vendors that want to support the iWmo and iJw standards in their product. We build a reusable messaging module that keeps pace with the annual releases, so your customers always run the current standard. See also our custom software.
Regional collaborations
Collaborative partnerships that handle message traffic centrally for several municipalities. A single integration processes the iWmo and iJw flows for the whole region, with clear logging per municipality and provider. See also our Suwinet integration for work and income.
Technology we use
We build iWmo and iJw integrations on the official message specifications of the iStandaarden, combined with the backend stack that suits you. The exact choice depends on your existing administration and the connection to the GGK or VECOZO — so your own team can manage the integration and keep up with new releases.
For the Long-Term Care Act, see our page on an iWlz integration.
Why choose Appfront for your iWmo and iJw integration?
Appfront has extensive experience building integrations with government and sector standards for a wide range of organisations in the Netherlands. We always begin with a thorough analysis of your existing systems and processes. An integration should not only work technically, but also add practical value to the way your administration operates.
For every integration, we write clear documentation and make sure your own team, or any future supplier, can understand and manage it. No black box, just transparent code and clear agreements on monitoring, alerting and maintenance.
You work with a dedicated point of contact who understands both the technical and the functional side. This keeps communication short, prevents misunderstandings and speeds up decisions when choices need to be made during development.
See also the Inlichtingenbureau integration (operator of the GGK) and the Wmo and youth care software where this message traffic lands. You can also explore our wider services around software for municipalities, municipal websites and custom software, or get in touch directly about your situation.
- Experience with integrations on government and sector standards in the social domain
- Built exactly to the official iWmo and iJw message specifications
- Familiar with connecting to the GGK (Inlichtingenbureau) and VECOZO
- Secure by default: PKIoverheid, secrets in vaults, role-based access
- Structured validation and error handling of response messages
- Comprehensive logging and monitoring from day one
- Clear documentation your team can read and manage
- A fixed point of contact, no account managers passed around
- Delivered alongside the annual iStandaarden releases
- A way of working aligned with your existing software landscape
Security and privacy for iWmo and iJw integrations
Wmo and Jeugdwet message traffic contains special category personal data about care provided to vulnerable clients. Appfront builds to the OWASP ASVS security standard. This means, among other things: connection to the GGK and VECOZO using PKIoverheid certificates, secrets held in secure vaults, role-based access and regular audits of message flows, with data minimisation as the starting point.
We document the data flows, message processing and connections to the hubs so that your record of processing activities is complete and you can demonstrably comply with the GDPR. Every processed message is logged with a traceable audit trail, so your organisation can demonstrably stay in control of data exchange in the social domain.
Working on other government domains too? Take a look at our Suwinet integration for work and income, or our AI for municipalities.
- GDPR-compliant data processing and data minimisation
- PKIoverheid certificates for connecting to the GGK and VECOZO
- Encryption in transit (TLS 1.2+) and at rest
- Role-based access and least-privilege principles
- Audit logs with traceable message flows
- Automatic retries and dead-letter queues
- Monitoring and alerting for anomalies
- Documentation for your record of processing activities
Frequently asked questions about iWmo and iJw integrations
Answers to the questions we are asked most often about iWmo and iJw integrations.
iWmo and iJw are the iStandards for electronic message traffic between municipalities and care providers under the Wmo and the Jeugdwet (Youth Act). An integration allows your own system to process these standardised messages automatically: the assignment (301), the start message (305), the stop message (307) and the claim (323), including the associated response messages. On the municipal side, transport runs via the Municipal Data Hub (GGK) of Inlichtingenbureau, and on the provider side via VECOZO. Appfront builds the integration into your care or municipal administration so that messages no longer need to be imported or retyped by hand.
iWmo and iJw are closely related standards from the same iStandards suite, managed by Zorginstituut Nederland (the Netherlands Health Care Institute). They work on the same principles and use the same message numbers and message flow. The difference lies in the law and product categories: iWmo covers support under the Wet maatschappelijke ondersteuning (Social Support Act), such as assisted living, sheltered housing and assistive devices, while iJw covers youth care under the Jeugdwet (Youth Act). Many municipalities and providers use both standards side by side, and Appfront builds the integration so that a single integration handles both.
The integration supports the standard messages from the Wmo and Jeugdwet message traffic: the allocation (301) and its return message (302), the request for allocation (315) with return (316), the request for change (317) with return (318), the start-of-care notification (305) with return (306), the end-of-care notification (307) with return (308), and the declaration (323) with the return declaration (325). The older declaration and invoice messages 303 and 304 are being phased out with the transition to iWmo 3.1. We set up exactly the message flows your organisation needs.
On the municipal side, message traffic is originated and received via the Municipal Data Hub (GGK, Gemeentelijk Gegevensknooppunt), which is managed by the Inlichtingenbureau. Care providers connect via VECOZO. The messages are structured XML following the iWmo and iJw message specifications; the underlying transport runs over Digikoppeling. Appfront builds the integration between your own administration and the correct hub, with validation of messages against the current specification and correct processing of return messages.
The cost depends on the number of message flows you want to automate, whether it concerns iWmo, iJw or both, the connection to the right hub (GGK or VECOZO), and the degree of custom work in your own administration. Handling of return messages, error handling, monitoring and ongoing maintenance also factor in. We always provide a clear quote following a no-obligation analysis of your situation and your existing software landscape.
Yes. Wmo and Jeugdwet message traffic involves special category personal data relating to care, so care is essential. The connection to the GGK and VECOZO runs over secure channels with PKIoverheid certificates. Appfront builds to the OWASP ASVS: secrets held in secure vaults, encryption in transit and at rest, role-based access and full logging of all processed messages. We document the data flows so that your record of processing activities stays complete and you can demonstrate GDPR compliance, with data minimisation as the starting point.
Yes. Appfront takes over the maintenance of existing integrations, even if they were originally set up by another party. We review the message processing, the validation against the specification, the error handling and the connection to the node, document the current set-up and draw up improvement proposals. Because the iStandaarden get a new release every year, we also keep your integration up to date with version updates.
An integration is relevant for municipalities that want to automate their Wmo and youth administration, for care providers who want to process message traffic directly in their own care administration, for software vendors in the social domain who want to support the standards in their product, and for regional partnerships that handle message traffic centrally for multiple municipalities. Whether you connect via the GGK on the municipal side or via VECOZO on the provider side, Appfront builds the integration to suit your role in the chain.
Ready to build your iWmo and iJw integration?
Tell us whether you want to integrate iWmo, iJw or both, which message flows you need and whether you connect via the GGK or VECOZO — we're happy to help you think through the connection, validation and return processing. A no-obligation first conversation gives you a clear picture of the possibilities within half an hour. Get in touch for an advisory session.