HubSpot COS Development: Custom Themes, Templates & Websites
Your website should win leads, not wait on a developer for every change. We build custom HubSpot COS websites, with themes, templates and modules written in HubL and React, that load fast, match your brand and let your marketing team create new pages in HubSpot's drag-and-drop editor. Every form, page and email connects straight to your HubSpot CRM, so you can see which content turns visitors into customers.
How we build HubSpot COS websites marketers enjoy using
Many HubSpot sites end up as one of two things: a bought marketplace theme stretched far beyond what it was made for, or a hard-coded build that only a developer can change. We build the middle path. You get a custom theme based on your design system, made of reusable modules with clear fields, so marketers can launch campaigns on their own while the site stays fast and on brand.
Under the hood, we work the way software engineering teams do. Themes live in Git and deploy through the HubSpot CLI, modules are written in HubL or in React with HubSpot's React + HubL framework, and every release is tested before it goes live. Speed, accessibility and technical SEO are checked on every template, not left for an afterthought.
Custom themes, not stretched templates
Your colours, fonts and spacing become theme settings, so a brand refresh is a settings change rather than an expensive rebuild.
Modules your marketers can actually use
Every module has clear, limited fields and sensible defaults, so pages stay consistent and beautiful no matter who builds them.
React where interactivity matters
Calculators, product configurators and filters are built as React modules that render on the server and load JavaScript only where needed.
HubSpot COS development services
From a single high-converting landing page template to an entire enterprise website migration, these are the HubSpot COS capabilities we engineer.
Custom HubSpot theme development
A complete theme built from your design files, with global settings, page templates, headers, footers and a library of reusable modules.
HubL and React module development
Hero banners, pricing tables, testimonial sliders, resource libraries and interactive tools, each with fields that are easy for editors to fill in.
Landing page & website templates
Conversion-focused templates for campaigns, product launches and events, with HubSpot forms, smart CTAs and native A/B testing ready to use.
HubSpot email template development
Custom coded and drag-and-drop email templates that render reliably across Outlook, Gmail and Apple Mail while matching your brand identity.
Blogs, resource centres & HubDB pages
Blog templates, filterable resource libraries, team directories and location pages powered by HubDB tables updated like a spreadsheet.
Memberships, portals & personalisation
Gated content and customer portals built with HubSpot memberships on Content Hub Enterprise, plus smart content that adapts by lifecycle stage.
Multi-language website architectures
Language versions of every page, translated modules and localized switchers, with strict hreflang tags set up correctly for international SEO.
Theme audits, fixes & speed optimisation
For existing HubSpot sites that feel sluggish or messy: unused modules pruned, scripts optimized, broken templates fixed and Core Web Vitals boosted.
Custom CRM App Cards & integrations
Embedded UI panels inside HubSpot records displaying live ERP billing and user accounts; fully migrated to modern extensions before the Oct 2026 cutoff.
Moving your website to HubSpot COS
Coming from WordPress, Webflow, Drupal or a custom-built site? We rebuild your templates as a clean HubSpot theme, migrate your content, and map every old URL to its new address to protect your search rankings and backlinks.
Content & SEO audit
We crawl your current website, inventorying every URL, top-ranking organic page and essential external backlink.
Theme build
Your page templates are rebuilt as native HubSpot modules with agreed UX, accessibility and design improvements.
Content migration
Pages, blog posts, author profiles, category tags and media assets are transferred and verified one by one.
301 Redirect map
Every old URL is mapped directly to its new address through server-side 301 redirects configured in HubSpot.
Launch & monitoring
We execute domain cutover, inspect Google Search Console, crawl for broken links and track ranking stability post-launch.
Built for speed, search and accessibility
A HubSpot website only pays off if people find it, it loads quickly and everyone can use it. We build all three into every template from day one.
Technical SEO
Clean semantic heading hierarchy in every module, editable meta tags, schema markup for articles, FAQs and products, with automated sitemaps and canonical tags.
Speed & Core Web Vitals
Lazy-loaded imagery, HubSpot automatic WebP resizing, minimal JavaScript bundles and zero bloated third-party libraries, verified on real mobile devices.
Accessibility (WCAG 2.2 AA)
Templates engineered to strict WCAG 2.2 AA guidelines with compliant colour contrast, keyboard-accessible navigation and mandatory alt-text fields on all image modules.
Website and CRM working as one
Because your site runs on HubSpot, every visit, form and email already lands in your CRM. We make the most of that connection, and extend it where your business needs more.
Lead capture & routing
Forms feeding lead scoring algorithms that route high-value qualified leads to designated sales reps within minutes.
Personalised pages
Dynamic smart content modules that adapt based on the visitor's lifecycle stage, target industry or browsing behavior.
Two-way integrations
Bi-directional sync with Odoo ERP, Stripe or custom PostgreSQL databases so web inquiries become orders and invoices without re-typing.
Modern app cards
Interactive UI panels inside HubSpot records showing data from your external platforms, safely migrated before legacy cards deprecate.
How we use AI in HubSpot development
Breeze, HubSpot's built-in AI, helps marketers draft and repurpose content inside Content Hub, and we set it up with your brand voice. We also use AI in our own delivery, with a developer reviewing every result.
Faster module builds
AI drafts module boilerplate, JSON schemas and field definitions so developers spend their time refining layout aesthetics and interactive edge cases.
Automated QA & audits
Automated test scripts crawl every template for broken links, missing alt text, heading hierarchy gaps and asset payload weight before launch.
Smarter content migrations
AI assists in mapping unstructured legacy HTML into modern modular HubL fields and suggests redirect pairs, verified by human editors.
Ready to build your
HubSpot COS & CRM Development?
Share your specifications with us. An engineering lead in your region will review your requirements, sign mutual NDAs, and provide architectural notes within 24 business hours.
Modern developer workflows on the HubSpot platform: Git version control, the HubSpot CLI, HubDB, server-side React components, and enterprise APIs.
HubSpot websites for your industry
We build HubSpot COS websites and dynamic templates tailored to the unique conversion paths and operational data of key industry sectors.
Brand storefronts, headless lookbooks and campaign landing pages that feed customer segmentation directly into your CRM.
Product and clinician resource portals, gated clinical whitepapers via memberships, and accessible WCAG-compliant design.
Interactive loan and savings calculators engineered as React modules, with compliance audit trails and approval gates.
Instant freight quote request flows, location landing pages generated dynamically from HubDB, and regional service directories.
Technical product catalogues and spec sheet downloads powered by HubDB, plus distributor partner portals.
Dynamic property listings from HubDB with interactive search filters, floor plan downloads and automated inquiry routing to agents.
Course catalogues, curriculum enrolment landing pages, webinar registrations and multi-language student hubs.
Solar savings estimators, interactive project case study libraries, and certified installer locator directories.
Thought leadership resource centers, interactive ROI estimators, automated demo booking and multi-touch lead qualification.
How a HubSpot COS website project runs: AI speed meets specialist judgment.
AI accelerates our team through every stage, while a senior technical specialist owns every architectural and UX decision.
Inquiry & Scoping
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Why choose Steigern Tech for HubSpot COS development
You get designers, HubSpot developers and integration engineers in one cohesive team, so your website, CRM and business software are built to work together from day one.
HubSpot developers who write real code
HubL, React and TypeScript with Git version control, peer code reviews and automated CI validation on every release.
Marketers stay in complete control
Editor-friendly modules and hands-on training ensure your marketing team launches pages and campaigns without waiting on a developer.
More than a website, under one roof
We also build CRM integrations, Odoo ERP backends and custom web apps, so your site connects to whatever your business runs on.
You own everything
Your theme code lives in your private Git repository and your own HubSpot portal, with 100% intellectual property assignment and zero lock-in.
10+ years, 200+ projects
Since 2014 we have delivered software platforms and high-converting websites for clients across Europe, the US, Australia and Asia.
Support across time zones
With operational delivery hubs in Ahmedabad and Melbourne, we schedule working-hour overlap with clients across the US, UK and Asia-Pacific.
Ways to work with us
Choose the model that fits your website goals, team capacity and budget timeline.
Website build or redesign
A brand-new HubSpot COS website or a complete platform rebuild, including full content migration and SEO preservation, for a guaranteed fixed price.
Theme and template project
A focused development sprint, such as custom campaign landing page templates, email design systems, or a bespoke HubL & React module library.
HubSpot development retainer
Reserved monthly engineering hours dedicated to building new modules, publishing campaign pages, speed improvements and ongoing enhancements.
HubSpot COS development FAQs
Answers on the platform, editing, themes, migration, timelines and cost.
A partner who's already shipped in your category.
Depth compounds. Our hubspot cos & crm development practice has shipped production software for high-scale enterprise clients — your architecture is a recognisable pattern, not an experiment. See live portfolio work across industries.
10+ years, 200+ projects
Since 2014, we've shipped hubspot cos & crm development solutions across Europe, the US, and Asia — your category is a known quantity, not a discovery engagement.
AI embedded, not bolted on
Intelligent features are designed into the architecture from sprint zero — not added as afterthoughts when roadmap pressures mount.
Global delivery, one team
Follow-the-sun delivery across US, UK, and Asia-Pacific overlap means your engineering roadmap never waits for a timezone to wake up.
Code you own on Day 1
Direct Git commits pushed directly into your private repository from the first sprint. Clean documentation, zero IP lock-in, and 100% intellectual property ownership.
Production standards by default
Strict automated CI/CD quality gates, ISO 27001 data practices, deterministic regression test suites, and zero unvetted dependencies in production.
Enterprise scale guaranteed
Architectures engineered to handle concurrency spikes, multi-tenant databases, and seamless horizontal cloud auto-scaling with sub-second response times.
Ready for a HubSpot website your team can run? Let's talk this week.
Share your current site and your goals, and within one business day a senior HubSpot developer will send you a recommended approach (new theme, redesign or migration), a sitemap outline, a timeline and a budget range. There is no obligation to go ahead.