WordPress Plugin and Block Development for UK Businesses

Built for UK SMEs, charities, professional services firms and distributed teams around London, Manchester, Birmingham, Bristol, Edinburgh and teams working nationwide. Focused, documented functionality that fits the editor and can be maintained safely. We account for plain UK English with accessible, task-focused content, cards, Direct Debit and regulated Open Banking or Pay by Bank providers where they fit the journey, and practical delivery in GMT/BST.

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Our approach

Block-first code, built to ship .

UK organisations do not need a generic overseas template. They need custom WordPress plugin and block development shaped around a competitive market where credibility, accessibility and a low-friction enquiry or checkout journey strongly affect conversion, internal ownership and the tools their customers already recognise. The build includes namespaced code, capability checks, sanitisation, escaping, upgrade paths and documentation instead of hiding business logic in a theme.

Our output is production grade. block.json metadata, strict attribute types, dynamic render where state matters, deprecations for every shipped version. Your editors get a clean Gutenberg experience. Your developers get code they can read and extend.

  • Written specification with attributes, schema and editor flows before build
  • Proper block.json, dynamic render, view script modules
  • Translation ready with full text domain and POT files
Custom Gutenberg block and plugin development in progress

Built for the United Kingdom

How custom WordPress plugin and block development works in the United Kingdom

UK SMEs, charities, professional services firms and distributed teams operate in a competitive market where credibility, accessibility and a low-friction enquiry or checkout journey strongly affect conversion. We shape the custom WordPress plugin and block development around those buying habits, plain UK English with accessible, task-focused content, straightforward proposals, sensible estimates and pricing in pounds, and the systems already used by the team. The result is a practical service plan for teams building trust and sustainable growth across the UK.

Practical UK use cases

Editorial block

Give content teams a controlled component with the right fields, variants and accessibility behaviour. For teams around London, Manchester, Birmingham, Bristol, Edinburgh and teams working nationwide, we define the local audience, ownership and follow-up route before implementation and account for cards, Direct Debit and regulated Open Banking or Pay by Bank providers where they fit the journey.

Business workflow

Turn a repeated manual task into a permission-aware WordPress workflow with a clear audit trail.

Product integration

Package an external service or data source behind a stable WordPress interface.

What we account for in the United Kingdom

Privacy and responsible data

We minimise unnecessary collection and document forms, analytics, processors and retention choices with the UK GDPR and Data Protection Act 2018, with security and privacy-by-design guidance from the ICO in mind. Technical implementation supports your compliance work; it does not replace legal advice.

Local operations and integrations

The delivery plan can account for cards, Direct Debit and regulated Open Banking or Pay by Bank providers where they fit the journey, pricing in pounds sterling, plain UK English with accessible, task-focused content, and a UK region when contracts, latency or organisational policy make local hosting preferable. We only add local integrations that serve a real customer or operational need.

Delivery in your working day

Planning, reviews and support are organised around GMT/BST. The build includes namespaced code, capability checks, sanitisation, escaping, upgrade paths and documentation instead of hiding business logic in a theme. Handover is written for the people who will publish, approve and support the site locally.

Local regulatory references are implementation context, not legal or regulatory advice. Your organisation remains responsible for confirming the obligations that apply to its sector and use of personal data.

How it works

From spec to shipped plugin in four steps.

A practical delivery process for UK teams, with decisions documented in GMT/BST and local operational requirements agreed before build work begins.

01

Discovery and spec

We map user stories, data model, attribute schema, editor UX and render semantics. You get a written specification and fixed quote before any code is written.

02

Build and iterate

WordPress engineers build the plugin or blocks in clean PHP and TypeScript. block.json first, proper supports, sensible defaults. Weekly staging demos keep you in the loop.

03

Testing and hardening

PHPUnit, Playwright, WordPress coding standards, PHPStan and accessibility audits on every block. Deprecations tested against prior shipped versions so existing content never breaks.

04

Ship and support

We package the plugin, generate POT files, tag a release and hand over a README plus a video walkthrough. Optional retainer for updates and future blocks.

What's included

Everything for a production plugin .

  • Custom Gutenberg blocks with proper block.json metadata
  • Dynamic render via render.php or render_callback
  • View script modules for frontend interactivity
  • Block patterns, variations and block styles
  • Custom plugin architecture with activation and uninstall hooks
  • REST API routes with schema validation and permission callbacks
  • Deprecations, migrations and backward compatible attributes
  • Full i18n with text domain, POT file and translator comments
  • PHPStan, WordPress Coding Standards and PHPUnit coverage
  • 30 day post launch support included
How we compare

Why product teams choose us over the alternatives.

Not all plugin work is equal. Here is how we stack up against a typical freelancer and a traditional agency.

WP Pro Devs
Freelancer
Traditional agency
Gutenberg engineers only
Fixed quote before work
block.json, dynamic render, view modules
Deprecations and migrations included
White label friendly
Typical turnaround
2 to 10 weeks
Varies
3 to 6 months
Starting price
£2.5k
£300
£10k+
Post launch support
30 to 90 days
None
Retainer only
WP Pro DevsRecommended
  • Gutenberg engineers only
  • Fixed quote before work
  • block.json, dynamic render, view modules
  • Deprecations and migrations included
  • White label friendly
  • Typical turnaround2 to 10 weeks
  • Starting price£2.5k
  • Post launch support30 to 90 days
What clients say
WP Pro Devs successfully migrated the site, achieving the client's desired website speed score and copying over all meta tags and descriptions. The team delivered on time and within budget and communicated excellently via virtual meetings. They were committed to aftercare and detail.
M
Michael CairnsDirector · Celsius Plumbing and Heating (Edinburgh) Ltd
640+Projects delivered
4.9 / 5Average rating · 180 reviews
82%Clients on retainer
Pricing

Transparent pricing, no surprises .

Fixed quotes before work begins. Choose the tier that fits your scope or ask for a custom estimate.

Launch offer20% off every plan
Ends in
--D--H--M--S
−20%
Starter
was £2.5k to £5k
£2k to £4k

One custom Gutenberg block with clean editor UX, dynamic render and full i18n.

  • One custom Gutenberg block
  • Editor and frontend views
  • block.json with strict attributes
  • Full i18n and POT file
  • 30 day post launch support
Most popular−20%
Studio
was £5k to £8k
£4k to £6.4k

Multi block plugin with patterns, variations and a small admin settings screen.

  • Up to 4 custom blocks
  • Block patterns and variations
  • Plugin wrapper with activation hooks
  • Basic admin settings screen
  • WordPress Coding Standards
  • 60 day post launch support
−20%
Scale
was £8k to £16k
£6.4k to £12.8k

Full plugin product with REST routes, admin UI, migrations and PHPUnit coverage.

  • Unlimited blocks within scope
  • REST API routes with schema
  • Custom admin UI with React
  • Deprecations and migration script
  • PHPUnit and Playwright coverage
  • 90 day support plus 1 training session
−20%
Enterprise
was £16k+
£12.8k+

Commercial plugin build with licensing, update server and a dedicated engineer.

  • Everything in Scale
  • Plugin licensing and update server
  • Dedicated WordPress engineer
  • SLA with priority response
  • Ongoing retainer available
  • Custom handover and onboarding
Quality standards

Every plugin ships production ready .

A plugin is not done until it passes our internal checklist. No shortcuts, no loose ends.

WordPress Coding Standards

PHPCS with WordPress ruleset clean on every file. No silenced warnings, no selective excludes.

PHPStan level 8

Static analysis at level 8 with WordPress stubs. Types on hooks, filters and REST responses.

PHPUnit coverage

Unit and integration tests for core logic, REST routes and migration paths. CI gates on green.

Playwright editor tests

Real Gutenberg browser tests. Insert block, edit attributes, save, reload, assert output.

WCAG 2.2 AA accessible

Keyboard flow in the editor, labelled controls, semantic output, contrast checked in all themes.

Deprecations verified

Every attribute change ships a deprecation. Existing content rendered against prior versions in tests.

i18n and POT files

Full text domain coverage, translator comments, POT generated on build, RTL friendly markup.

Clean, documented code

Inline docs, PHPDoc blocks, README and a changelog your team can read.

Packaged and tagged

Build script, ZIP artifact, semver tag and release notes for every shipped version.

For agencies

Your clients. Our blocks. Your brand.

We are the silent engineering team behind dozens of design and marketing agencies. Your client sees your work, your invoice and your brand. Our name never appears in the plugin header or the editor.

  • 01

    Fully branded delivery

    Plugin header, readme and admin screens carry your brand, not ours.

  • 02

    Dedicated partner engineer

    One point of contact for all your plugin work. Shared Slack channel, weekly syncs, fast replies.

  • 03

    Transparent partner pricing

    Retainer rates, bulk discounts and priority scheduling for agency partners.

  • 04

    Your stack, not ours

    We plug into your Linear, ClickUp, Notion or Jira. No tool switching, no friction.

How white label delivery works

01
You

Brief the scope

You share the block or plugin specification in your stack. Linear, Notion, wherever you already work.

02
We

Scope and partner quote

We write a detailed technical specification and send you a partner rate quote. Never shown to your client.

03
You

Add margin, quote your client

You mark up, brand the proposal and present it on your letterhead at your price.

04
Client

Client approves the scope

Your client signs off on your terms, with your brand, and pays you directly.

05
We

We build under NDA

Silent build on branded staging. No credits in the plugin header, readme or editor UI.

06
You

Deliver as your own

You review, accept handover and ship the plugin to your client under your agency name.

Common questions

What clients ask us before they start.

Yes. Planning, reviews and support can be organised around GMT/BST. We agree response expectations, meeting windows and escalation contacts before the project or care plan starts.
Start your plugin

Tell us what you need built.

Share your plugin or block requirements and a WordPress engineer will respond with a written estimate and timeline within one business day.

  • Free scoping call and written estimate within 24h
  • Fixed quote before any work begins
  • WordPress engineer on your project from day one
Book a 20-min scoping call
[email protected]
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WordPress Plugin & Block Development in the UK | WP Pro Devs