Shopify app developer Bournemouth

Shopify App Developer Bournemouth: Custom Solutions for Your E-commerce Growth

Shopify app development, in 2026, involves creating bespoke software solutions that extend the core functionality of the Shopify platform. This goes beyond simple theme customisation or configuring existing third-party apps. A custom Shopify app provides unique capabilities tailored precisely to your business processes, integrating deeply with your store's data and workflows. This distinction is crucial. While theme customisations alter the aesthetic and foundational layout of your storefront using Liquid and front-end technologies, and existing apps offer pre-packaged features, a custom app addresses needs that off-the-shelf solutions cannot meet. For example, if you require specific inventory management logic not available in any existing app, or a unique customer loyalty program tied directly to first-party data and internal CRM, a custom app is the answer. It can connect your Shopify store with proprietary internal systems, automate complex fulfilment processes, or offer a distinct customer experience that differentiates you from competitors. Our work as a Shopify app developer in Bournemouth focuses on building these specialised applications, whether they run fully within the Shopify Admin, as storefront extensions using Shopify Functions and UI Extensions, or as headless applications consuming Shopify's robust APIs. We ensure these solutions are built to Shopify's latest standards, prioritising security, scalability, and performance to seamlessly integrate with your existing Shopify Plus or standard Shopify infrastructure.

This service differs significantly from general web development or even broader e-commerce platform development. While a general web developer might build a standalone application, a Shopify app developer possesses specific expertise in the Shopify ecosystem: its GraphQL Admin API, Storefront API, App Bridge, Polaris design system, webhooks, and app extension points like Shopify Functions (e.g., for custom checkout validations) and UI Extensions (e.g., modifying the order details page in the Admin). This specialised knowledge is vital for ensuring your app is robust, maintainable, and passes Shopify's rigorous app review if intended for the App Store, or simply performs optimally as a private app for your store. We do not generally build full e-commerce websites from scratch on other platforms; our specialisation lies within the Shopify environment, understanding its nuances and limitations to build effective and compliant applications. This focused approach allows us to deliver high-quality, deeply integrated solutions that enhance your Shopify store's capabilities, rather than just adding another layer on top.

What is a Shopify App?

A Shopify app is an application that integrates with a Shopify store to add new features or extend its functionality. Apps can be public (available in the Shopify App Store) or private (developed for a specific store or a small group of stores). Public apps typically serve a broader audience and adhere to stricter security and performance requirements from Shopify. Private apps are built specifically for one merchant's unique needs and are not listed in the App Store. Both types of apps interact with Shopify's APIs to read and write data, respond to events (via webhooks), and extend the user interface. This is distinct from a Shopify theme, which controls the visual appearance and basic structure of your storefront. While themes use Liquid for templating, apps can be built using a wide range of programming languages and frameworks (e.g., Node.js, Ruby on Rails, Python, React, Vue.js) and are hosted independently, communicating with Shopify via secure API calls.

Who This Is For

Our custom Shopify app development services are for UK businesses operating on Shopify or Shopify Plus that encounter specific operational bottlenecks, require unique customer experiences, or need to integrate their e-commerce operations deeply with internal systems. You likely have exhausted standard solutions and find that off-the-shelf apps either lack specific functionality, are too rigid, or create unnecessary complexity.

1. High-Growth D2C Brands (Revenue: £1M - £10M; Team: 10-50 people): You're experiencing rapid growth, but your manual processes for order fulfilment, inventory management, or customer service are becoming unsustainable. You need to automate steps that are unique to your product or business model, which existing apps don't handle. For example, a bespoke app could automate the bundling of specific product combinations based on customer purchase history or integrate with a niche third-party logistics (3PL) provider that doesn't offer native Shopify integration, saving significant staff time. Your current pain point might be excessive manual data entry or reconciliation between systems, leading to errors and delays.

2. Specialised Retailers with Complex Product Configurations (Revenue: £500k - £5M; Team: 5-25 people): Your products have highly customisable options, intricate pricing rules, or specific assembly requirements that are beyond Shopify's standard variant system or product customisation apps. You might be selling made-to-order furniture, bespoke jewellery, or items with complex component selections. The pain here is often customers being unable to configure products accurately online, leading to pre-sale queries, order errors, and returns. A custom app can provide a sophisticated configurator, generate dynamic pricing, or feed exact specifications directly to your manufacturing system.

3. Wholesale/B2B Sellers on Shopify Plus (Revenue: £2M - £20M; Team: 15-75 people): While Shopify Plus offers B2B functionality, your wholesale operations might have unique pricing tiers, advanced payment terms, custom order approval workflows, or specific customer portal requirements that are not fully met by Shopify's out-of-the-box solution or general B2B apps. You might need an app that integrates with an existing ERP for real-time stock availability specific to B2B customers, or one that automates tiered discount thresholds based on historical order volume. Your pain is often a disjointed B2B experience, requiring manual intervention for pricing adjustments or order processing, which slows down sales and increases administrative overhead.

4. Brands Integrating with Niche Enterprise Resource Planning (ERP) or Customer Relationship Management (CRM) Systems (Revenue: £1M+; Team: 10-100 people): Your business relies on a specific, perhaps older or highly customised, ERP or CRM system for its core operations, and you need seamless, real-time data sync with Shopify. Generic integration apps often provide only basic synchronisation or require hefty manual data mapping. A custom integration app ensures that product data, stock levels, customer information, and order details flow accurately and consistently between Shopify and your critical internal systems, reducing data discrepancies and improving operational efficiency. The current pain is significant manual effort in data transfer, potential for errors, and lack of a unified customer view across systems.

Common Problems We Solve

We build custom Shopify apps and integrations that address specific operational inefficiencies, enhance customer experience, and enable unique business logic that existing solutions cannot provide. Our focus is on automation, data integrity, and tailored functionality.

1. Automating Complex Order Fulfilment Workflows (e.g., UK-based bespoke gift box retailer): A UK client, a growing online retailer specialising in customisable gift boxes, faced significant manual overhead. Customers could select individual items to build a gift box, leading to hundreds of unique product combinations and complex packing instructions. Their team spent approximately 15-20 hours per week manually extracting order details, cross-referencing component stock, generating pick lists, and preparing custom packing slips with specific assembly notes. This led to errors in 5-8% of orders and delayed dispatch.

   • Our Solution: We developed a private Shopify app that integrated with their product catalogue and order data. The app automatically parsed each custom gift box order, generated a dynamic pick list for warehouse staff based on component and variant SKUs, and produced a custom-formatted packing slip with detailed assembly instructions specific to that order. It also flagged any component stock discrepancies in real-time, preventing orders from being processed incorrectly.
   • Before: 15-20 hours/week manual work, 5-8% order error rate, delayed dispatch.
   • After: <1 hour/week manual oversight, <0.5% order error rate, same-day dispatch for 95%+ orders. The client saved roughly £15,000-£20,000 annually in reduced labour and error correction costs, achieving this within 10 weeks of the app's deployment.

2. Synchronising Shopify with Niche or Legacy ERP Systems (e.g., UK industrial supplies wholesaler): A UK industrial supplies wholesaler, operating on Shopify Plus, struggled with real-time inventory and pricing synchronisation between their Shopify store and a highly customised, on-premise ERP system (developed over 20 years ago). They were manually updating stock levels on Shopify twice daily and processing price changes based on manual exports from the ERP. This meant customers often saw incorrect stock statuses online, leading to backorders or cancelled sales, and pricing updates were delayed by up to 12 hours. This led to approximately 10-15 customer service tickets daily related to stock discrepancies and inaccurate pricing.

   • Our Solution: We built a robust integration app, hosted on AWS, that acted as a bridge between Shopify's GraphQL Admin API and their ERP's exposed SOAP API. The app featured bi-directional synchronisation: real-time stock updates from ERP to Shopify (triggered by ERP events), and confirmed order placement from Shopify back to the ERP. Pricing updates from the ERP to Shopify were scheduled hourly, ensuring near real-time accuracy. Error handling mechanisms were built in, alerting the client's IT team to any sync failures with detailed logs.
   • Before: 2-3 hours/day manual data reconciliation, 10-15 daily customer service tickets related to data errors, lost sales due to inaccurate stock.
   • After: <30 minutes/week oversight; customer service tickets related to data errors reduced by 90%; accurate real-time stock and pricing, leading to increased customer satisfaction and fewer abandoned carts due to perceived 'out of stock' items. The project was delivered in two phases over 18 weeks.

3. Implementing Custom B2B Logic for Wholesale Portals (e.g., UK food & beverage distributor): A UK food and beverage distributor using Shopify Plus for both B2C and B2B sales needed advanced B2B functionality. They required custom pricing tiers based on customer group and order volume, specific payment terms (e.g., 30-day invoice for approved accounts), and a custom order approval workflow for large B2B orders. Shopify Plus B2B features were insufficient for their granular requirements. Manual processing for these B2B orders took valuable sales team time, approximately 20% of their day.

   • Our Solution: We developed a private app that extended Shopify's order processing capabilities. It integrated with their customer tags to apply dynamic pricing rules at checkout based on pre-defined tiers. For payment, it presented approved B2B customers with an "Invoice Me" option, automatically generating an invoice within the Shopify order and flagging it for their accounting system (via integration with Xero API) with specified payment terms. It also introduced an order approval step for large wholesale orders, routing them to a sales manager before fulfilment.
   • Before: Manual pricing adjustments, manual invoice generation, delayed B2B order processing, 20% sales team time spent on administrative tasks.
   • After: Automated pricing and invoicing, streamlined B2B order workflow. Sales team time on administrative B2B tasks reduced by 75%, allowing them to focus on sales generation and customer relationships. Implementation completed in 14 weeks.

How We Deliver It

Our Shopify app development process is structured, transparent, and iterative, ensuring the solution precisely meets your requirements while adhering to best practices. We are based in Bournemouth but deliver services remotely across the UK.

Phase 1: Discovery & Planning (2-4 Weeks)

We begin with in-depth discovery sessions with your key stakeholders. This involves understanding your existing workflows, pain points, specific use cases, and technical environment. We identify the core problem the app aims to solve and define clear, measurable objectives. This phase includes:

• Requirements Gathering: Detailed discussions to document functional and non-functional requirements. We use tools like Miro for collaborative whiteboarding and JIRA for tracking specific user stories and acceptance criteria.
• Technical Feasibility Assessment: Evaluating the viability of integrating with your specific third-party systems or legacy software. This includes reviewing API documentation (e.g., your custom ERP API, Shopify GraphQL Admin API capabilities, or specific payment gateway APIs) and assessing data models.
• Solution Architecture Design: Proposing the optimal architecture for your app. This involves deciding whether it's a server-side app (Node.js/Ruby on Rails), a client-side app (React/Vue.js), or a headless component using Shopify Functions and UI Extensions. We design the data flow, database schema (e.g., PostgreSQL, Supabase), and hosting environment (e.g., AWS, Render). For complex data, we might consider a Supabase backend leveraging Row Level Security (RLS) for multi-tenancy if the app were to serve multiple merchants.
• Wireframing & Prototyping: Creating basic visual representations of the app's user interface, particularly for admin-facing apps, to ensure alignment on user experience before heavy development begins. We might use Figma for this.
• Detailed Project Plan & Proposal: Finalising scope, timeline, and cost estimates. We establish communication channels and reporting structures.

Phase 2: Development & Iteration (8-16 Weeks)

This is the core build phase. We work in agile sprints, typically 2 weeks long, allowing for regular feedback and adjustments.

• Environment Setup: Configuring development, staging, and production environments, including version control (Git using GitHub/GitLab), CI/CD pipelines (e.g., GitHub Actions, Vercel), and database setups (e.g., Supabase, Heroku Postgres).
• Core Feature Development: Building the app's functionality according to the agreed-upon design. We use established frameworks and libraries for stability and maintainability. For a typical app, this might involve:
  • Backend: Node.js with Express or NestJS, Ruby on Rails, or Python with Django/Flask. We interact with Shopify via their official API libraries or direct GraphQL/REST calls. For instance, creating webhooks for orders/create or products/update events, using the Shopify GraphQL Admin API for complex data queries, or the Shopify Storefront API for front-end experiences. We implement robust error handling, logging (e.g., Sentry), and rate limit management for Shopify APIs.
  • Frontend (for Admin apps): React.js or Vue.js, often utilising Shopify's Polaris React components for consistent UI within the Shopify Admin. This ensures a native feel and familiarity for your team.
  • Database: PostgreSQL or a NoSQL alternative depending on data structure and scale. Supabase is a common choice for its PostgreSQL support, authentication, and real-time capabilities.
• API Integrations: Connecting with any required third-party services, such as ERPs, CRMs, shipping carriers, or payment gateways. This often requires careful management of API keys, authentication tokens (OAuth 2.0 where applicable), and data mapping logic. We implement comprehensive retry mechanisms and circuit breakers for external API calls to manage transient failures.
• Automated Testing: Writing unit tests (e.g., Jest, RSpec) and integration tests to ensure code quality and prevent regressions. This forms a critical part of our CI/CD pipeline.

Phase 3: Testing & Quality Assurance (2-4 Weeks)

Before launch, the app undergoes rigorous testing.

• Functional Testing: Verifying that all features work as specified in the requirements.
• User Acceptance Testing (UAT): You and your team test the app in a realistic environment, providing feedback. This is crucial for ensuring the app meets your operational needs.
• Performance Testing: Checking the app's speed and responsiveness under expected load conditions. We monitor response times and resource utilisation.
• Security Auditing: Ensuring data is handled securely, adhering to UK GDPR principles, and protecting against common vulnerabilities. This includes secure storage of sensitive data, robust authentication, and authorisation checks. We follow Shopify Partner standards for app security.
• Bug Fixing & Refinement: Addressing any issues identified during testing.
• Deployment Planning: Preparing for the production launch, including data migration strategies if applicable.

Phase 4: Deployment & Launch (1-2 Weeks)

The app is deployed to your production environment.

• Production Deployment: Deploying the app code to the chosen hosting platform (e.g., AWS EC2/ECS, Render, DigitalOcean). Setting up monitoring and alerting.
• Post-Launch Monitoring: Closely observing the app's performance and stability immediately after launch.
• Training & Documentation: Providing your team with necessary training and comprehensive documentation for ongoing app use and basic troubleshooting.

What Success Looks Like

Success for a custom Shopify app is measured by its tangible impact on your business operations, customer experience, and ultimately, your bottom line. We define clear Key Performance Indicators (KPIs) early in the project to track this success.

• Reduced Manual Hours/Costs: This is often the most immediate and quantifiable benefit.
  • KPI: Percentage reduction in staff time spent on a specific manual task.
  • Realistic Range: 60% - 95% reduction for highly automated processes.
  • When to See It: Within 1-2 months post-launch, as your team adapts to the new system. For example, if an app automates order validation, you might see a reduction of 10-15 hours/week for an Operations team member within the first month.
• Improved Data Accuracy & Consistency: Eliminating errors that stem from manual data entry or disjointed systems.
  • KPI: Reduction in data discrepancies reported (e.g., stock errors, pricing mismatches, fulfilment errors).
  • Realistic Range: 80% - 99% reduction in error rates.
  • When to See It: Within 1-3 months. For an inventory sync app, you would expect near-zero discrepancies between your Shopify store and ERP within weeks of stabilisation.
• Enhanced Customer Experience (CX): Leading to higher satisfaction, repeat purchases, and potentially higher Average Order Value (AOV).
  • KPI: Increase in customer satisfaction scores (e.g., CSAT, NPS), reduction in customer support tickets related to specific issues, or increase in conversion rates for complex products.
  • Realistic Range: 5% - 20% improvement in relevant CX metrics.
  • When to See It: 3-6 months. For an improved product configurator, you might see a 10% uplift in conversion rate for those products within 3 months, alongside a reduction in pre-sale enquiries.
• Increased Operational Efficiency/Throughput: Processing more orders, faster, with fewer resources.
  • KPI: Shorter order fulfilment times, increased order processing capacity, reduced lead times for custom products.
  • Realistic Range: 15% - 50% improvement in process speed.
  • When to See It: 2-4 months. An app streamlining warehouse picking might reduce average dispatch time by 20% within the first two months.
• Scalability & Future-Proofing: The ability for your e-commerce operations to grow without immediately straining resources or processes.
  • KPI: Ability to handle X% increase in order volume or product catalogue size without proportional increase in manual labour.
  • Realistic Range: Designed to support a 50% - 200% increase in scale.
  • When to See It: Not a daily metric, but tested during peak seasons or periods of rapid growth. The app should perform stably and avoid becoming a bottleneck as your business expands.

For a custom Shopify app developer in Bournemouth, our goal is to not just build software, but to deliver a measurable return on your investment, making your business more efficient and competitive.

Tools, Platforms and Standards We Work With

Our development stack and methodologies are chosen for their robustness, scalability, security, and alignment with modern development practices and industry standards.

Core Development Stack

• Backend Languages & Frameworks: Node.js (with Express.js or NestJS), Ruby on Rails, Python (with Django or Flask). Our choice often depends on project requirements, team expertise synergies, and existing client infrastructure.
• Frontend Frameworks: React.js, Vue.js. For Shopify Admin-embedded apps, we heavily utilise Polaris React components to ensure a native user experience.
• Databases: PostgreSQL (often via Supabase or Heroku Postgres for Managed Services), MongoDB (for specific use cases requiring flexible schema). We ensure secure data storage and querying.
• Cloud Hosting & Infrastructure: Amazon Web Services (AWS) (e.g., EC2, Lambda, S3, RDS), Google Cloud Platform (GCP), Render, or Vercel for frontend deployments. Our infrastructure is designed for high availability and scalability.
• Version Control: Git, hosted on GitHub or GitLab for collaborative development and code reviews.
• CI/CD: GitHub Actions, GitLab CI/CD, or Vercel deployments for automated testing and deployment pipelines.
• Monitoring & Logging: Sentry.io for error tracking, CloudWatch (AWS) or Stackdriver (GCP) for application performance monitoring and logging.

Shopify Specific Tools & APIs

• Shopify GraphQL Admin API: For comprehensive data access and manipulation of store resources like orders, products, customers, and more. We use this for complex queries and mutations.
• Shopify REST Admin API: Utilised for simpler, high-volume operations where REST endpoints are more straightforward or for older integrations.
• Shopify Storefront API: For building custom storefronts (headless commerce) or specific front-end experiences that require direct customer context.
• Shopify App Bridge: Facilitates seamless integration of client-side apps within the Shopify Admin UI, enabling actions like redirecting within the admin or displaying toast messages.
• Shopify Functions: For extending Shopify's core logic directly at critical points like checkout (e.g., custom shipping rates, payment gateway rules, product discounts). This replaces much of the functionality previously handled by Shopify Scripts.
• Shopify UI Extensions: For building custom user interfaces within areas of the Shopify Admin, such as order details pages, product pages, or customer profiles, offering a truly integrated experience.
• Webhooks: For real-time event notifications (e.g., orders/create, products/update), enabling asynchronous processing and ensuring data synchronisation.
• Theme App Extensions: For embedding app features directly into your theme without manual code modifications, simplifying installation and updates.

Standards & Compliance

• UK GDPR & ICO: We build apps with data privacy by design. This includes minimising data collection, ensuring secure data storage (encryption at rest and in transit), implementing data retention policies, and facilitating data subject rights requests. All data processing adheres to UK GDPR guidelines and the regulations set by the Information Commissioner's Office (ICO). We ensure clear data processing agreements are in place for any data we handle on your behalf.
• WCAG 2.2 (Web Content Accessibility Guidelines): For any user-facing components of the app (especially front-end UI extensions), we design and develop to meet WCAG 2.2 Level AA accessibility standards. This ensures your app is usable by individuals with disabilities, broadening your reach and improving user experience for everyone.
• Core Web Vitals: We optimise app performance to contribute positively to your store's Core Web Vitals scores, particularly for storefront-facing apps or UI Extensions. This includes efficient code, optimised asset delivery, and lazy loading strategies to ensure fast loading times, responsiveness, and visual stability.
• Shopify Partner Program Standards: As a Shopify Partner, we adhere to Shopify's best practices for app development, including security, performance, and UI/UX guidelines, whether building public or private apps. This ensures long-term compatibility and stability.
• HMRC Making Tax Digital (MTD): If your app involves tax or accounting data (e.g., integration with Xero or other accounting software), we ensure that any data exchange or reporting capabilities comply with HMRC's MTD regulations, particularly for VAT returns.
• Payment Card Industry Data Security Standard (PCI DSS): While we do not process credit card data directly within our apps (this is handled by Shopify's secure checkout), any app dealing with sensitive customer data is developed with PCI DSS implications in mind, ensuring no card data leakage and adherence to secure data handling practices.

UK-Specific Considerations

Developing Shopify apps for the UK market requires a specific understanding of local regulations, operational nuances, and user expectations. Our presence as a Shopify app developer in Bournemouth and our UK-wide remote capabilities mean we are well-versed in these requirements.

UK GDPR and ICO Compliance

Data protection is paramount. The UK General Data Protection Regulation (UK GDPR), enforced by the Information Commissioner's Office (ICO), governs how personal data of UK residents is collected, processed, and stored. For any custom app we build that handles customer data – from order history to contact details – we embed compliance from the design phase.

• Data Minimisation: We only collect and process data strictly necessary for the app's function.
• Secure Processing: All data in transit and at rest is encrypted. We design secure authentication and authorisation mechanisms to control access to sensitive data.
• Transparency: If your app collects new data or processes existing data in novel ways, we advise on updating privacy policies to inform your customers clearly.
• Data Location: For some UK businesses, data residency is a concern. We can discuss hosting options (e.g., AWS regions within the EU or UK where technically feasible and required) that align with your data residency policies, though it's important to note that Shopify itself operates on a global infrastructure. We ensure that any third-party services we integrate with also have robust GDPR compliance policies.

HMRC and Tax Regulations

Apps dealing with financial data, product pricing, or order management must account for HMRC (Her Majesty's Revenue and Customs) regulations.

• VAT Calculations: While Shopify handles core VAT, custom apps that introduce complex pricing rules, discounts, or integrate with accounting systems like Xero, must ensure accurate VAT calculations and reporting. We can integrate with tax APIs or ensure your app's logic correctly applies UK VAT rates.
• HMRC Making Tax Digital (MTD): For B2B integrations, ensuring that data relevant for MTD (e.g., VAT details from orders) is accurately captured and can be submitted to MTD-compliant accounting software is critical.
• Export/Import Rules: If your app supports international sales or specific duties for UK-EU trade, we ensure the logic considers current trade agreements and customs declarations.

Accessibility Standards (WCAG 2.2)

The UK Equality Act 2010 implies a requirement for websites and digital services to be accessible to people with disabilities. Building to WCAG 2.2 (Level AA) standards for any user-facing parts of your app is not just about compliance but also about inclusivity and expanding your customer base. Our development ensures:

• Keyboard Navigation: All interactive elements can be accessed and operated using only a keyboard.
• Screen Reader Compatibility: Content is structured semantically for screen readers, with appropriate ARIA attributes.
• Colour Contrast: Sufficient contrast between text and background colours.
• Clear Labelling: Form fields and interactive elements have clear, descriptive labels.

Specific UK Operational Nuances

• Payment Gateways: Integration with common UK payment processors beyond Shopify Payments (e.g., Klarna, Clearpay, or specific B2B payment terms apps).
• Shipping Carriers: Integration with popular UK parcel carriers for custom fulfilment logic (e.g., Royal Mail, DPD, Hermes/Evri).
• Address Validation: Using UK-specific address validation services to improve delivery accuracy.

Our team in Bournemouth provides onsite support to businesses within Dorset and the surrounding South Coast. For clients further afield in the UK, we operate effectively through established remote collaboration tools and practices, ensuring seamless project delivery wherever you are located. Our local knowledge as a Shopify app developer in Bournemouth, combined with our UK-wide remote capabilities, ensures your custom app is not just technically sound, but also perfectly attuned to the UK market.

Why Streamline Digital

Choosing Streamline Digital means partnering with a specialised team that understands the technical intricacies of Shopify and the commercial realities of running an e-commerce business in the UK. We are not a generic web development agency; our specialisation in Shopify and AI workflow automation provides a focused expertise for your project. As a Shopify app developer in Bournemouth, we are committed to transparent, technically sound, and results-driven development.

Our technical lead brings over two decades of software engineering experience, including significant work with large-scale data platforms and complex integration projects before focusing on e-commerce. This deep technical background means we approach app development with a focus on robust architecture, maintainability, and scalability, not just feature delivery. We don't rely on off-the-shelf templates or low-code solutions for custom app development; every solution is hand-coded to your precise specification.

Experience in Action: Anonymised UK Project Example

We recently completed a complex integration for a UK luxury goods retailer (a multi-million pound business) struggling with inventory allocation across multiple sales channels and bespoke order kitting. Their pain point was a "negative stock" scenario in Shopify whenever high-value products sold simultaneously on their website and through their wholesale partners' portals, leading to over-selling and customer disappointment. Their existing ERP wasn't designed for real-time inventory reservation.

Our solution involved building a private Shopify app that acted as a real-time inventory control layer. We integrated it with Shopify's GraphQL Admin API for product and order updates, an external API from their wholesale platform, and a direct database connection to their legacy SQL Server ERP for granular stock data. The app implemented a custom reservation logic: when a customer added an item to their cart on any channel, the app temporarily reserved that stock in the ERP via API before checkout completion. It also validated stock availability in the ERP during the Shopify checkout process using Shopify Functions, preventing over-selling. Over a 16-week project timeline, including discovery, development, and a 4-week UAT phase, this app eliminated over-selling by 100% (previously 1-2 instances per day for high-value items) and reduced order fulfillment errors related to unavailable stock by 95%. This directly translated into increased customer satisfaction and an estimated recovery of £50,000 in lost sales and administrative costs within the first six months.

Our Commitment to You:

• No Lock-in: We believe you should own your custom app. All intellectual property for the app we develop vests with you upon final payment. We provide all source code, documentation, and handover procedures.
• Transparent Pricing: We provide detailed proposals with clear cost breakdowns, typically structured as fixed-price for defined scopes or on a time-and-materials basis for evolving projects. We avoid hidden fees. Pricing for a custom Shopify app can range from £15,000 to £50,000+ GBP, depending on complexity, number of integrations, and functionality. Small, single-purpose apps might start lower, while multi-system integrations with complex logic will be at the higher end.
• Focused Expertise: We won't try to be a jack-of-all-trades. Our specialisation means we can deliver high-quality, deeply integrated Shopify solutions efficiently.
• No White-Label Resellers: You work directly with the Streamline Digital team. We don't offshore development to unknown third parties without your explicit knowledge and consent.

If a Shopify app project encounters unforeseen technical challenges or scope creep (which we actively manage to minimise), we communicate transparently and provide solution options along with revised timelines and costs. Our aim is to build a long-term partnership based on trust and tangible business value.