Custom Jortt integration development
Appfront builds custom Jortt integrations that automate your bookkeeping and invoicing, from your webshop, CRM, point-of-sale system or own application. Via the Jortt API and OAuth 2.0, we synchronise sales invoices, customers, quotes, expenses and ledger entries, so you never enter anything twice. You save hours of admin each month and your figures in Jortt stay up to date at all times.
What is a Jortt integration?
Jortt is Dutch online accounting software widely used by freelancers and SMEs. Alongside invoicing, VAT returns and bank integrations, Jortt offers an open API that lets you connect your administration to other systems. This means sales invoices, customers, quotes and expenses can be created automatically from where the work already happens, such as your webshop or CRM.
In practice, a custom integration means: creating sales invoices based on orders or time registration, keeping customers and relationships in sync in both directions, applying VAT rates correctly, recording expenses and ledger entries, and, where wanted, handling direct debit collection via Mollie with a mandate. The integration removes duplicate entry and manual re-typing.
Appfront builds according to the official Jortt API documentation and the OWASP ASVS security standard. We align the data models, general ledger account mapping and error handling with your actual administrative processes, so the integration grows with your business and your figures in Jortt stay reliable.
No duplicate entry
Orders, hours or customer details from your own system appear automatically as an invoice or relationship in Jortt. You no longer retype anything, and you avoid discrepancies between your operations and your books.
Figures always up to date
Because invoices, customers and expenses land directly in Jortt, you always see your revenue, outstanding items and VAT position up to date. That saves work around the VAT return and gives you faster insight.
Secure via the Jortt API
The integration works through the official Jortt API using OAuth 2.0 and scoped permissions. This means each system only has access to what it needs, and your financial data stays protected.
Our development process for Jortt integrations
We follow a proven methodology that removes uncertainty early and delivers a stable integration. From an initial analysis of your bookkeeping, invoicing flows and source systems through to going live and ongoing management, every step is aimed at an integration your team can understand and trust.
We map out which invoices, customers or expenses you want to synchronise, which direction the data should flow, how VAT and ledger accounts are assigned, and whether direct debit collection via Mollie is relevant.
We design the architecture, choose between the authorisation code and client credentials flows, define the OAuth scopes, and set out a strategy for error handling and pagination.
Implementation with automated tests, structured logging and monitoring. You see working builds along the way.
Controlled go-live with data validation and a safety net, followed by ongoing management and further development.
What a Jortt integration delivers in practice
Every Jortt integration is tailored to your bookkeeping, invoicing flows and adjacent systems. Below are the features we most often deliver for organisations using Jortt as their accounting package.
Jortt API & OAuth 2.0
We integrate via the Jortt API (version 3) using OAuth 2.0: the authorisation code flow for apps that serve multiple administrations, or the client credentials flow for your own administration. Scoped permissions ensure each system only gains access to the resources it requires.
Sales invoice synchronisation
Orders, subscriptions or time entries are automatically turned into sales invoices in Jortt, with the correct invoice lines and VAT. Where required, we create credit notes, retrieve invoice PDFs, or send invoices by email or via Peppol.
Managing customers and contacts
We keep customers and relations in two-way sync between your CRM or webshop and Jortt, including address details, VAT numbers and payment terms. This way, invoices always refer to the correct, up-to-date customer details.
Exchanging quotes
We pass quotes (estimates) from your own system through to Jortt and track their status, such as draft, sent, expired or invoiced. An accepted quote can then move on to a sales invoice without any manual retyping.
Expenses, general ledger & VAT
We post expenses and bookings to the correct general ledger accounts in Jortt, using the right VAT rates. This keeps your ledger consistent and your VAT administration in order at the end of the quarter.
Direct debit via Mollie
For recurring payments, we set up direct debit via Mollie, with customer-level direct debit mandates in Jortt. Invoices are collected automatically and the payment status is fed back into your administration.
Typical use cases in practice
A Jortt integration looks very different from one organisation to the next. We see a number of patterns recur, and for each we have a proven setup with attention to invoicing, customer synchronisation and the correct VAT and general ledger logic.
Sole traders and freelancers
Self-employed professionals and freelancers who want to automate their invoicing. Hours or assignments from a scheduling or time-tracking tool are automatically turned into sales invoices in Jortt, so you spend less time on admin. See also our API integrations.
SMEs with multiple systems
SMEs with a CRM, point-of-sale system or planning tool that needs to stay in line with the accounting. We sync customers, invoices and expenses in both directions between Jortt and your core systems, so everyone works with the same, up-to-date figures. See also custom software.
Webshop & e-commerce
Webshops that want every order automatically booked in Jortt as a sales invoice with the correct VAT. Customers are created as relations, refunds become credit notes and, for subscriptions, direct debit via Mollie can be set up. Read more about our e-commerce development.
Accountancy and bookkeeping firms
Accountancy and bookkeeping firms managing multiple client administrations in Jortt. Using the authorisation code flow, we connect each administration and automate the import of invoices, expenses and general ledger postings, so your team has less manual work. See also middleware.
Technology we use
We build Jortt integrations with the official Jortt API (version 3) and OAuth 2.0, combined with the backend stack that suits you. The precise choice depends on your source systems and data flows, so your own team can manage or further develop the integration.
Why choose Appfront for your Jortt integration?
Appfront has extensive experience building API integrations for a wide range of organisations in the Netherlands. We always begin with a thorough analysis of your existing systems and processes, because an integration must not only work technically but also add practical value to your administration.
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.
You may also be interested in our wider services around API integrations, middleware, custom software development and web app development, or see our overview of integrations.
- Experience with the Jortt API, OAuth 2.0 and scoped permissions
- Specialists in bookkeeping and invoicing integrations for freelancers and SMEs
- Experienced with VAT logic, ledger mapping and direct debit via Mollie
- Secure by default with scoped rights, secrets held in vaults and TLS
- Structured error handling and retry mechanisms
- 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
- Ongoing maintenance and proactive further development
- A way of working aligned with your existing IT landscape
Security and privacy in Jortt integrations
A Jortt integration processes financial data and personal data of your customers, such as invoices, VAT numbers, addresses and direct debit mandates. Appfront builds to the OWASP ASVS. This includes: OAuth tokens and client secrets held in secure vaults, scoped OAuth permissions so the integration only accesses what is strictly necessary, encrypted traffic over TLS, and regular audits of the data flows.
Because financial data is involved, we apply data minimisation: the integration only requests the OAuth scopes it needs, for example only customers and invoices where that is the entire use case. We document the data flows and the data processed so that your record of processing activities is complete and you can demonstrate compliance with the GDPR. We rotate tokens and secrets on schedule and monitor traffic for anomalies.
More on our security approach: information security policy and CVD policy.
- GDPR-compliant data processing and data minimisation
- Encryption in transit (TLS 1.2+) and at rest
- Role-based access and least-privilege principles
- Audit logs with traceable data flows
- Automatic retries and dead-letter queues
- Monitoring and alerting for anomalies
- Secrets management in line with best practice
- Documentation for your record of processing activities
Frequently asked questions about Jortt integrations
Answers to the questions we are asked most often about Jortt integrations.
A Jortt integration is a technical link between Jortt and another system, such as your webshop, CRM, point-of-sale system or in-house application. Using the Jortt API (version 3) and OAuth 2.0, sales invoices, customers, quotes, expenses and general ledger entries are exchanged programmatically. This means you no longer need to enter data twice, and your bookkeeping in Jortt always stays up to date. An integration can be simple, such as turning new orders into invoices in Jortt, or more extensive, with two-way synchronisation of customers, VAT rates and direct debit mandates.
A Jortt integration is a good fit when you use Jortt as your bookkeeping software and want to synchronise your invoicing, customer details or expenses automatically from another system. Think of a webshop that books orders straight into Jortt as sales invoices, a point-of-sale system that passes on daily takings, or a CRM where customers and relationships need to match your bookkeeping. If you manage multiple administrations or are building an app for other Jortt users, we use the authorisation code flow; if you are building only for your own administration, the client credentials flow is sufficient.
A simple integration, such as automatically creating sales invoices in Jortt from orders, can go live within a few weeks. More extensive scenarios involving two-way synchronisation of customers, VAT rates, quotes, expenses, the general ledger and direct debit mandates via Mollie usually take longer. After an intake meeting in which we review your administration and systems, we provide a realistic estimate.
We work with the official Jortt API (version 3) and OAuth 2.0, combined with the backend stack that suits you, such as Node.js, Python, PHP, .NET or Ruby. Authentication runs via the authorisation code flow or the client credentials flow, with scoped permissions per resource such as customers, invoices, estimates and expenses. We take Jortt's rate limit and pagination into account, and build in reliable error handling and logging so that your bookkeeping remains consistent.
The cost is determined by the complexity of the data flows, the number of systems to be connected, the desired direction and frequency of synchronisation, and the amount of custom work in the bookkeeping logic, for example around VAT rates and ledger accounts. Ongoing management, monitoring and support also play a part. We always provide a clear quote after a no-obligation analysis of your situation.
Yes. A Jortt integration processes financial data and personal data of your customers, so security comes first. Appfront builds in line with OWASP ASVS: OAuth tokens and client secrets are kept in secure vaults, OAuth permissions are scoped so the integration only has access to what is strictly necessary, and traffic is encrypted via TLS. We work according to data minimisation principles and document the data flows so that your record of processing activities remains complete and you can demonstrably comply with the GDPR.
Yes. Appfront regularly takes over existing Jortt integrations, even if they were originally set up by another party. We review the API integration, the OAuth configuration, the error handling and the mapping of invoices, customers and ledger accounts, document the current setup and propose improvements. From that point on, we handle adjustments, extensions and monitoring, including timely rotation of secrets.
Jortt is Dutch online bookkeeping software that is popular with freelancers and SMEs. An integration suits self-employed entrepreneurs and freelancers who want to automate their invoicing, SMEs with multiple systems that need to stay in sync, webshops and e-commerce businesses that want to book orders as invoices, and accountancy and administration firms that manage client administrations. If you are unsure whether your situation is a good fit, we are happy to think it through with you in a no-obligation conversation.
Ready to build your Jortt integration?
Tell us which invoices, customers or expenses you want to automate and which system Jortt needs to connect to. We're happy to help with the right OAuth flow, VAT and ledger mapping, and direct debit collection via Mollie. A no-obligation first call will give you a clear picture of what's possible within half an hour.