Service · Software development

Custom housing association software development.

Custom software that works in and alongside Aareon, NCCW or Itris: tenant portals, maintenance requests, PassendToewijzen flows, AedesARC reporting and everything your core package doesn't do. Built for the Dutch housing association sector, with the Woningwet, BIO and GDPR built in.

Aareon / NCCWPassendToewijzenAedesARCWoonNetBIO & GDPR
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We don't replace Aareon — we build what's missing around it.

The Dutch housing association sector comprises around 280 housing associations, which together manage roughly thirty percent of the housing stock. Almost all of them run on Aareon (Tobias AX), NCCW, Itris, Empire or Cebus. These packages handle the financial core well: rent administration, debtors, general ledger. What they do less well: a modern tenant app, a maintenance reporting flow that seamlessly connects the maintenance engineer and contractor, a mutation process that runs from inspection through to re-letting without Excel islands, or an allocation tool that automatically checks PassendToewijzen.

We don't replace those core packages; for large-scale work that is rarely the right choice. We build the modules around them and on top of them. Integrated via API or web service with your existing administration, so the rent administration remains the source of truth and all new flows feed straight into it. The result: digital services that belong in 2026, without you having to migrate your core package.

We work for large housing associations that need Aareon add-ons, for mid-sized housing associations running on Itris or Cebus that want to modernise their processes, and for smaller housing associations that want to replace their own patchwork of Excel, emails and outdated portals with a single enterprise-grade suite. Managers of owners' associations (VvE) and the non-DAEB businesses of mixed housing associations are also part of this.

What sets our approach apart is that we genuinely understand what a housing association is. We know that a tenant is not a customer in the e-commerce sense, that a letting officer works with PassendToewijzen rather than a sales funnel, and that a contractor portal differs from a supplier portal because the maintenance chain has different SLAs and invoicing rules. We built that domain knowledge by sitting down with housing association staff during the scoping phase, not by rolling out a generic property management template.

If sustainability improvements to your portfolio are also on the agenda, that includes recording building surveys. How we build that survey layer alongside your housing association software is covered on building an energy label app.

Three types of project.

Depending on where things are currently stuck in your organisation. We advise which project fits during the first conversation; it often starts with a single pain point and grows organically.

Compact project · fixed sprint budget

Tenant portal or app

A secure private environment in which your tenant can view their contract, make payments, submit a maintenance report, check a housing cost overview and request changes. Login with DigiD or magic link, native integration with your rent administration and notifications by email or push.

DigiD loginContract viewingiDEALRent increase letter
Mid-sized project · fixed sprint budget

Maintenance and mutation flow

A single chain running from the tenant's report (with photo), through dispatching to your own maintenance service or regular contractor, all the way to hours registration and invoicing back into Aareon. The same applies to mutations: pre-inspection, repair, marketing photos, advertisement on WoonNet and re-letting in one timeline, with no more Excel alongside the package.

Field engineer appContractor portalWoonNet integrationPre-inspection
Larger project · fixed sprint budget

Sector suite with central control

A fully modular suite that runs alongside your core package: allocation with automatic PassendToewijzen and income checks, energy and sustainability tracking with label registration, AedesARC and SDC reporting, and neighbourhood dashboards for liveability. One login, one permissions model, one auditable source.

Alongside the primary process sits the annual accountability with dVi and dPi, with its own deadlines and its own accountant products. This is covered on the page about software for accountability under the Housing Act.

PassendToewijzenEP-onlineAedesARCSDC export

What you receive at the end.

No vendor lock-in and no black box. You receive the software, the codebase and the documentation to take everything in-house or have another party maintain it.

  • The software modules themselvesProduction and acceptance environments, running in your own cloud (Azure/GCP/AWS) or with us in a BIO-compliant Dutch hosting environment.
  • Full codebase and documentationSource code, build instructions, architecture overview and an API overview of all integrations with your core package and external registers.
  • Integration package with your core systemVerified integration with Aareon Tobias AX, NCCW, Itris, Empire or Cebus, including a mapping document so your IT team and the supplier know exactly which fields synchronise in both directions.
  • BIO and GDPR fileDPIA, risk analysis, baseline assessment and penetration test report, so your data protection officer and supervisory board can sign off at handover.
  • End-user training and admin guideTraining sessions for key users in lettings, property, finance and customer contact. Short video tutorials for engineers, contractors and tenants.
  • Management contract (optional)Ongoing maintenance, security patches, monitoring and further development. A fixed monthly fee with several response-time levels depending on the risk of the module.

When custom is the right choice.

Four patterns where we support housing associations. If you recognise one, we're happy to discuss what fits your situation.

Tenant experience

The vendor's portal falls short

The standard tenant environment from Aareon or NCCW covers the basics, but your tenants still phone to check their housing costs, to request a transfer or to report a repair. You want a proper app or a much better portal, under your own brand, with the flows that matter to you.

Maintenance chain

Contractors work from Excel

A report comes in, is emailed to the contractor, who works in their own administration, and the invoice comes back as a PDF that someone then re-keys into Aareon. The chain involves too much manual work and too little visibility of SLAs, lead times or tenant satisfaction.

Allocation and compliance

Passend Toewijzen takes too much manual work

Income checks, urgency assessment and rule-compliant allocation: your letting staff do this carefully, but manually and partly in spreadsheets. You want a tool that encodes the rules of the Housing Act and rent policy in software and automatically decides whether an allocation is suitable.

Reporting and steering

AedesARC and SDC take too much time

The annual Aedes report, the Aedes benchmark and the Social Data Catalogue each require their own data collection. You want a single source from which all sector reports are generated, with an audit trail and historical versions, rather than stitching spreadsheets together each time.

Energy and sustainability

Renovation programme not managed centrally

Your energy renovation programme spans hundreds or thousands of homes, with label tracking, subsidy applications and contractor coordination. That data is currently scattered across project management tools, EP-Online and your core system. You want one dashboard that shows how far the programme has progressed and which homes are falling behind.

Transfers and mutations

Transfer lettings grind to a halt

Chains of movers, where tenant A moves to B, freeing A's home for C, who moves into C's home for D, need tight coordination. A transfer flow without linked marketing and allocation leads to vacancies and lost rental income that could be avoided.

Not yet sure about a large project?

Test your idea first: a working prototype in 1 day

With OneDayBuild, we turn your idea into something tangible in one day for €1,150, so you can see whether further development is worth the investment. Decide to go ahead with the full build? Then we credit the full cost.

Explore OneDayBuild →

How a housing association project works with us.

1

Introduction and architecture scan

We map out which core system you run, which modules are connected to it, which departments are feeling the pain and which compliance requirements (Housing Act, BIO, GDPR) apply. No vague discovery document, but a concrete map of where the gains are.

2

Scope workshop with key users

A joint session with letting, property, finance and IT. We sketch the first screen flows, validate them with tenants or maintenance engineers, and decide which modules get built in which order — smallest pain point first, so you deliver demonstrable value within a few sprints.

3

Build in sprints with a live integration

Every sprint delivers a working build you can see running in acceptance, including the integration with your core system. Where possible, we involve Aareon, NCCW or Itris directly at the integration points, so there are no surprises later on.

4

BIO check and pen test

Before go-live, we run through the baseline assessment and have an independent penetration test carried out. We record the findings and mitigations in a dossier that your data protection officer and supervisory board can endorse.

5

Rollout and management

Phased rollout — first one neighbourhood or one type of property, then scale up. Training for your teams and short video explainers for tenants. After that, ongoing management for security patches and further development.

Compliance and standards included.

For a housing corporation, digitalisation is not just a technical matter — it is also a matter of regulatory oversight. That is why we build the relevant standards in from day one rather than adding them afterwards.

Sector regulations

Housing Act (social rental, income checks, DAEB/non-DAEB), rent policy and the WWS points system, annual rent increase rules and PassendToewijzen — encoded as business rules in code, not as reference material.

Information security

BIO (Baseline Information Security for Government) as the baseline for housing corporations, GDPR for tenant data, encryption in transit and at rest, audit trail as standard, role-based access at property level.

Registers and integrations

EP-online for energy label registration, BAG for address and building data, WoonNet and regional letting platforms, the Tax Authority for income verification, and of course your core system via smart API integrations.

Reporting standards

AedesARC for sector reporting, the Aedes benchmark, Aedes's Social Data Catalogue (SDC) as the sector data standard, and your own internal KPIs for the supervisory board and policy team — all drawn from a single source.

Frequently asked questions.

What letting, property and IT managers at housing corporations usually want to know before we start.

Do you replace Aareon, NCCW or Itris?
For large-scale work: no. Those systems handle the financial and administrative core well, and migrating away from them is a disproportionately heavy project. We build modules around them that integrate seamlessly via API or web service (tenant portal, maintenance, transfers, allocation, reporting), so the core system remains the source of record while your service becomes modern. For smaller housing associations running on heavily outdated Itris/PowerBuilder environments, partial replacement is sometimes worth considering, and we discuss that case by case.
Do you work with Power Automate or Microsoft 365?
Yes, where it makes sense. For lightweight workflows — a reporting form, an approval chain, a notify-contractor flow — Power Automate, Logic Apps and Microsoft 365 are sound building blocks, provided they land in a manageable pattern. For heavier work (transactional, high volumes, complex rules such as PassendToewijzen) we choose native code, because low-code ends up causing more pain than benefit there. We advise on the appropriate level for each module.
How does the integration with PassendToewijzen work?
PassendToewijzen is a calculation rule under the Housing Act: a housing corporation must allocate a property with a rent below the cap-off threshold to households entitled to housing benefit. We implement that rule as a decision tree in the allocation tool, combined with an income check via the Tax Authority (UWV-IB47 or the usual flow for this) and urgency categorisation. The result: the letting officer automatically sees whether a match is compliant, with an audit trail showing why it is or isn't.
Can you automate AedesARC and SDC reporting?
Yes. AedesARC and the Social Data Catalogue each ask for their own data definitions, but the underlying data largely comes from your core system and from modules we build. We set up a single integrated data model with version history, map it to the Aedes definitions, and generate the reports with an audit trail, so there is no more manual Excel cycle each year.
How does this fit with WoonNet or WoningNet?
WoonNet and regional rental marketplaces are where your vacant social rental homes are advertised and where prospective tenants respond. We build the integration: when a transfer is completed, the marketing module automatically generates a listing with photos and features, publishes it on WoonNet, receives responses back and routes them into the allocation flow. For regional platforms, we build the same integration to measure.
What determines the cost of this type of project?
Three variables weigh most heavily: the size of the housing association (the number of homes determines the complexity of rights and reporting), the number of modules built at the same time, and the complexity of the integration with your core system. Aareon Tobias AX has modern REST APIs, whereas NCCW and Itris sometimes require an intermediate layer. We always begin with a short architecture scan so we can speak transparently about scope and investment before the project starts.
How do you handle BIO and GDPR?
BIO (Baseline Informatiebeveiliging Overheid) applies to housing associations as the baseline for information security and covers large parts of what GDPR also requires for tenant data. We run the baseline assessment as part of every project, deliver a DPIA and risk analysis, and commission an independent penetration test before go-live. All output goes into a file that your Data Protection Officer and Supervisory Board can endorse.
Do you also work for small housing associations or only large ones?
Both. Large housing associations with more than twenty thousand homes often need Aareon add-ons and sector-wide reporting. Mid-sized associations with between five and twenty thousand homes typically opt for selective replacement of Itris or Cebus, or for a complete suite running alongside their existing administration. Smaller associations with fewer than five thousand homes often get a single integrated environment that replaces the patchwork of Excel, emails and legacy portals. Owners' association managers and non-DAEB businesses of mixed associations are included too.
How does this relate to a broader property project?
A housing association project shares a lot with broader property software projects, but the regulations and the target group make it fundamentally different: a commercial landlord does not need to handle PassendToewijzen or AedesARC. If your portfolio is mixed (social and private sector, or housing association and owners' association management), we combine the approach from our broader property software track with the housing association-specific modules on this page. For organisations focused purely on letting without social rental rules, our letting software track is also relevant.
How long does a project like this take?
That depends on the scope. A first module, for example just a tenant portal with DigiD login and contract viewing, can be working within a few sprints. A complete suite covering allocation, changes of tenancy, maintenance and reporting is a multi-sprint project over a longer period. We work iteratively: each sprint delivers a working build, so you can keep validating whether the direction is right and adjust course where needed.

Talk to us about your digital roadmap.

A thirty-minute introductory call, with no obligation. We listen to your core system, your pain points and your priorities for the coming years, and give direction where it is useful to you. Whether you are considering a single tenant app or preparing a multi-year digitalisation roadmap, a good first conversation is always worthwhile. We are also happy to work with you if you would first like to validate a field service app for your maintenance team before thinking more broadly.

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