Custom Drupal development and module development

When custom development is needed

Drupal is a flexible platform, but some requirements need custom code. Custom development is the right path when:

• the website must communicate with an external system (ERP, CRM, e-commerce, payment gateway, database);
• content management needs to support specific workflows that no ready-made module covers;
• complex roles, permissions or content visibility rules are required;
• the project needs a unique data model that does not fit standard Drupal content types;
• a migration requires importing data from an external source in a structured way.

What custom development covers

Custom Drupal modules

We write modules to Drupal API standards using hooks, plugins, services and events. Custom modules integrate with Drupal core and contributed modules, and critical behaviour is covered by automated tests.

API integrations

Whether the external system uses REST, JSON:API, SOAP, GraphQL or a proprietary API, we connect it to Drupal in the required direction. Integrations use Drupal's Migrate API, queues or cron as appropriate and include error handling and logging.

Typical Drupal integrations:

• ERP and accounting systems;
• CRM and sales pipeline tools;
• PIM and product catalogues;
• payment gateways and e-commerce services;
• authentication and SSO;
• registries, membership systems and permission checks;
• booking and accommodation systems;
• data exchange through public or internal APIs.

Before development, we agree the data flow, error handling, sync frequency and who can correct data manually.

Workflows and content moderation

Complex publishing workflows (Drupal Content Moderation), user roles, integration-specific permissions and content visibility rules for different user groups.

Content migration solutions

Content, users, files and metadata from older Drupal versions, WordPress, CSV or other sources — via Drupal Migrate, structured and verified.

Theme and front-end development

Drupal Twig theme development — component-based, responsive implementation tested against the agreed WCAG 2.1 AA scope.

How the work happens

1. Requirements analysis — clarify what the system needs to do and which users and workflows depend on the integration.

2. API review — check documentation, authentication, limits, test environment and error handling.

3. Architecture and solution design — decide whether to use a contributed module, write a custom module or integrate an external service. Often the right solution combines them.

4. Development and tests — code, automated tests for critical functionality, code review.

5. Monitoring and maintenance — review logs, errors and cron or queue reliability, and agree who responds when the external API changes.

6. Handover — work instructions, code comments and support with early questions.

Examples of custom work

• Palmako — 50+ custom modules for five international sites, external API sync for product catalogues and pricing
• Riigi Kinnisvara AS — custom procurement module, automated portfolio import from an external property API
• Eesti Kaubandus-Tööstuskoda — member e-commerce integration, event registration system, member directory with API