Freelance Web Developer (Independent Contractor) — Backend-Heavy

About the role We are an established decking company running a portfolio of advanced, heavily customised websites, and we're looking to bring on a senior freelance web developer for ongoing, tracked hourly work. While there is front-end work involved, the core of this role is backend — building, integrating, and maintaining the server-side systems that tie our multisite network, e-commerce, CRM, email, and automation layers together. This is a long-term technical partnership, not a one-off project. Important: We work directly with independent contractors only. Please, no agencies, white-label shops, or sub-contracting middlemen. Architecture overview (indicative, not exhaustive) CMS & multisite: WordPress Multisite network with multiple connected subsites E-commerce: WooCommerce (catalogue, checkout, payments, order lifecycle) Backend services: Java services, PHP (WordPress core/hooks), REST APIs Frontend: React components and custom interactive UI Infrastructure: In-house server administration; you work alongside it (staging, deploys, environment config) Backend work — the core of this role This is where most of your time will go. We need someone who is genuinely strong server-side, not a front-end dev who "also does backend." Expect to work on: API design & integration — Building and consuming REST APIs to connect our subsites, CRM, email system, and third-party services. Designing clean endpoints, handling auth (OAuth/API keys/JWT), rate limiting, pagination, and error handling. Java service layer — Maintaining and extending our Java backend services; writing reliable, testable server-side logic that sits behind or alongside the WordPress layer. WordPress backend (advanced) — Custom plugins, hooks/filters, custom post types, the WP REST API, cron jobs, and multisite-aware logic. Going well beyond themes and page builders — actual PHP development. WooCommerce backend — Custom order flows, payment gateway integration, webhook handling, inventory/stock logic, and programmatic product/order management via the WooCommerce API. Database work — Schema design, query optimisation, indexing, and cleanup. Diagnosing slow queries, reducing autoload bloat, and keeping the DB healthy across a multisite environment. Data synchronisation & middleware — Building the "glue" that moves data reliably between systems: WordPress ↔ CRM ↔ emailer ↔ analytics. Queues, scheduled jobs, retry logic, and idempotent syncs so nothing double-fires or drops. Automations & workflow logic — Server-side automation: lead routing, triggered emails, CRM pipeline updates, and API-driven background processes. Webhook receivers and event-driven flows. Server-side tracking & data layer — Backend conversion tracking infrastructure (e.g. server-side GTM / measurement APIs), reliable event capture, and a clean data layer that survives ad-blockers and browser restrictions. Performance (backend side) — Object/page caching strategy, transients, reducing PHP execution time and TTFB, and tuning the stack so the front-end has a fast foundation to build on. Security & reliability — Input sanitisation, nonce/CSRF handling, secure API credentials, logging, and sensible error monitoring. Front-end & marketing work (supporting) Still part of the role, but secondary to the backend: React components and custom interactive UI New subsites within the multisite network Landing pages and funnels CRM subsite and email/emailer subsite (build + integrate) GTM containers, GA4, conversion tracking, event tagging Core Web Vitals / PageSpeed Insights improvements What we're looking for Strong backend track record: PHP (advanced WordPress), Java, and REST API design/integration Real WordPress Multisite and WooCommerce development experience (custom plugins, not just config) Solid database skills (MySQL/MariaDB): schema design, query optimisation, debugging Experience building integrations, webhooks, and middleware between systems Working knowledge of server-side tracking, GTM/GA4, and data layers Comfortable in a server-admin-supported environment (staging → production discipline) Competent enough on the front-end (React) to deliver end-to-end when needed Independent, clear communicator, documents their work Engagement terms Tracked hourly work (time-tracker required) Independent contractors only — no agencies Ongoing, long-term relationship for the right person Please share: portfolio links (ideally backend / multisite / API / WooCommerce work), hourly rate, and weekly availability To apply Tell us about a backend-heavy project you've delivered — ideally involving API integration, multisite, WooCommerce, or data synchronisation between systems — and how you architected it.