Diadem One – CRM, Invoicing & Email Marketing

Run more of your business without leaving WordPress.

Diadem One brings customer relationship management, invoicing, email marketing, task tracking, products, services, and business data together in one streamlined WordPress workspace.

Designed for small businesses, freelancers, agencies, consultants, nonprofits, ministries, and growing teams, Diadem One helps you organize customer information, manage daily follow-ups, create professional invoices, and communicate with your audience from the WordPress dashboard you already know.

Need More? Upgrade to OneSuite Enterprise

Diadem One gives you essential business-management tools at no cost. When your organization needs more advanced capabilities, you can move to OneSuite Enterprise and expand into the broader OneSuite business platform.

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Diadem One and OneSuite are developed by Diadem Technologies.

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Manage Contacts and Customer Relationships

Turn WordPress into a practical customer relationship management system.

Create detailed contact and company records, organize relationships with tags, assign lifecycle stages, add custom fields, record notes, and keep important customer information accessible in one place.

Diadem One can help you manage:

• Leads and prospects
• Customers and clients
• Companies and organizations
• Vendors and business partners
• Members, donors, and supporters
• Contact notes and history
• Customer statuses and lifecycle stages

Create and Send Professional Invoices

Prepare customer invoices directly from WordPress using saved contacts, products, and services.

Add billing details, due dates, descriptions, quantities, and pricing through a simple invoice editor. Generate printable PDF invoices, email them to customers, and update their status as they move through your billing workflow.

Invoice features include:

• Customer billing information
• Reusable products and services
• Multiple invoice line items
• Quantities and unit pricing
• Due-date management
• Printable and downloadable PDFs
• Email invoice delivery
• Sent, paid, and void status tracking

Build Email Marketing Campaigns

Create customer newsletters, promotions, announcements, and follow-up campaigns from your WordPress dashboard.

Diadem One includes a visual HTML email composer, media support, personalized contact fields, audience selection, campaign previews, and plain-text backup content. Your marketing contacts remain connected to the customer records already stored in your CRM.

Use email marketing to send:

• Customer newsletters
• Product and service announcements
• Special offers and promotions
• Company updates
• Educational content
• Event announcements
• Customer follow-ups

Track Tasks and Important Follow-Ups

Keep customer-related work from falling through the cracks.

Create tasks, assign priorities, set due dates, update progress, and organize the actions your business needs to complete. Track proposals, invoice reminders, customer calls, campaign preparation, and other responsibilities from one central workspace.

Organize Products and Services

Maintain a reusable catalog of the products and services your business offers.

Save product names, service descriptions, SKUs, pricing, product types, and tax settings. Catalog items can then be used when preparing invoices, helping you reduce repetitive data entry and maintain consistent pricing.

Customize Your CRM

Every business collects different information. Diadem One includes custom fields that allow you to extend contact and company records with details that match your organization and workflow.

Whether you need to track customer preferences, account information, membership details, service requirements, or internal classifications, custom fields help you adapt Diadem One to the way you work.

Import and Export Your Business Data

Bring existing information into Diadem One and maintain portable copies of your records with built-in import and export tools.

This makes it easier to migrate customer information, update records in bulk, and retain control of your business data.

Diadem One Features

• WordPress CRM
• Contact management
• Company management
• Lead and customer tracking
• Lifecycle stages and statuses
• Contact tags, notes, and history
• Custom contact and company fields
• Product and service catalog
• Customer invoice creation
• PDF invoice generation
• Invoice email delivery
• Invoice status tracking
• Email marketing campaign builder
• Visual HTML email composer
• Personalized email fields
• Plain-text email alternatives
• Marketing contact management
• Task and follow-up tracking
• Task priorities, statuses, and due dates
• Data import and export
• Unified WordPress admin interface

Built for Small Businesses and Growing Organizations

Diadem One is a strong fit for:

• Small businesses
• Freelancers and independent professionals
• Consultants and coaches
• Creative and marketing agencies
• Local service providers
• Nonprofit organizations
• Churches and ministries
• Membership organizations
• Customer-focused teams

One Connected Business Workspace

Stop piecing together disconnected tools for contacts, invoices, email campaigns, products, and tasks.

Diadem One gives you a connected WordPress business management experience that helps your organization stay informed, organized, and ready to serve customers.

Install Diadem One and start managing your customer relationships and everyday business operations directly from WordPress.

Diadem One stores its business records in OneSuite’s canonical local WordPress tables so compatible records can remain available when moving to OneSuite by Diadem Enterprise.

WooCommerce catalog synchronization is not included in Diadem One. Diadem One can retain and use compatible shared product records created by another OneSuite edition, while its own products and services remain native OneSuite records for invoicing.

The included Diadem One functionality does not expire and does not require a paid license.

Email delivery and external services

Email campaigns use WordPress mail or an SMTP server explicitly configured by a WordPress administrator.

When an administrator configures and enables SMTP, recipient addresses, message subjects, message content, and the configured sender credentials are transmitted to that administrator-selected SMTP provider as necessary to deliver email. Diadem One does not select or contact an SMTP provider automatically.

The SMTP password is stored locally in encrypted form using a key derived from the site’s WordPress authentication salt. It is never displayed back in the browser. OneSuite preserves the administrator-configured sender settings during edition transitions so replacing Diadem One does not silently disable an established mail transport.

OneSuite plugin administration pages contain optional links to Diadem websites for information about OneSuite Enterprise and payment-processing services. These links are user-initiated navigation only; the plugin does not contact those sites merely because it is installed or activated.

Data retention

Uninstalling Diadem One intentionally preserves canonical OneSuite business records, including CRM and invoice data, so uninstalling or changing editions does not destroy business data used by another OneSuite edition.

Transient Free-only mail locks and transport observations are removed on uninstall; the administrator-configured sender settings are preserved for OneSuite edition continuity.

Development / Source

Diadem One includes human-readable source for the custom JavaScript files that are whitespace-compressed for distribution.

Readable source mappings:

• src/js/free-invoice-editor.js -> assets/free-invoice-editor.js
• src/js/free-email-composer.js -> assets/free-email-composer.js

No transpiler, npm package, webpack configuration, proprietary compiler, or external build dependency is required for these files. The production files are whitespace-compressed equivalents of the readable source and are kept in the plugin package together with their source for review.

To verify that the documented source and production files are present, run this command from the plugin directory with Node.js installed:

node build/verify-js-source.js

For release maintenance, changes should be made first in the corresponding file under src/js/, reviewed in human-readable form, and then whitespace-compressed into the matching file under assets/ without changing behavior.

License

Copyright © 2026 Diadem Technologies. Licensed under the GNU General Public License v2 or later.

Diadem One is licensed under GPLv2 or later. Original plugin code and original bundled plugin graphics are distributed under the same GPL-compatible terms. Third-party components, where present, retain their original copyright and compatible license notices.