Web application development
Web application development is needed by companies for which a standard website or ready-made SaaS solution is no longer enough. A browser-based solution can be used to set up user accounts, automate employee workflows, accept payments, manage orders, collect analytics, or connect multiple internal company systems.
Custom web application development
Seo-Gen develops web applications from scratch: from task analysis and architecture design to testing, launch, and further development. Functionality, technologies, and deployment methods are tailored to specific processes, workloads, security requirements, and scalability plans.
Custom development begins with the company processes that the future product must support. First, we determine who will use the system, what actions different roles perform, where the data comes from, and which external services it needs to exchange data with. Only then can we evaluate the architecture, interfaces, and required development scope.
Web application development services are especially in demand where an off-the-shelf platform requires constant workarounds. A custom project can be built around an existing CRM, ERP, customer database, or other software environment, while maintaining the company's preferred operating logic.
What business problems does a web application solve?
A web application can replace several disparate services or automate a specific process that was previously performed manually. For example, an employee receives a request, verifies the data, changes the status, and passes the task on, and the client sees the latest results in their account without having to call a manager.
A single app lets you manage orders, documents, payments, reservations, reports, and notifications. The solution is also suitable for B2B portals, internal corporate systems, and services where users access personal data after authorization.
Typical tasks look like this:
- automation of repetitive employee operations and data transfer between departments without manual copying;
- creation of accounts for clients, partners, dealers or suppliers with different access rights;
- accepting orders, requests, payments and documents with status tracking in a shared system;
- integration with CRM, ERP, accounting, delivery, telephony and third-party APIs;
- creating analytical dashboards with metrics collected from multiple sources.
Before development, these tasks are translated into user scenarios and requirements. This approach helps us understand which features are truly needed in the first version and which can be moved to later stages.
When is development from scratch necessary?
Developing web applications from scratch is justified when ready-made platforms don't support the required business logic or require too much manual customization. This often occurs with complex role systems, unusual integrations, large amounts of data, or a specific sequence for processing operations.
Turnkey web app development is also a popular choice for companies planning to launch a standalone digital product. In this case, the architecture must accommodate audience growth, the addition of new modules, and functionality changes once the first users arrive.
Developing from scratch is appropriate when it's necessary to retain control over the application logic, codebase, and infrastructure. However, each feature should be justified by a business need, as unnecessary modules increase development time and cost, as well as future support costs.
When is a ready-made solution more cost-effective than custom development?
A ready-made service is more efficient when a company's processes are standard and fully align with the functionality of an existing product. For example, for a simple CRM, booking form, or small internal accounting system, developing a separate system may be more expensive than subscribing to a suitable platform.
Before ordering web app development, it's helpful to compare the cost of a custom product with the out-of-the-box solution over several years. Consider licensing, pricing plan limits, integration costs, potential data transfer, and dependency on third-party platform capabilities.
What web applications do we develop?
The application format is determined by the task, users, and the set of operations to be performed within the system. A single project can combine the functions of a SaaS, a client account, an administrative panel, and an analytics service, so the division into types is used primarily for structural design.
Seo-Gen reviews each project individually. At the outset, mandatory functions, roles, integrations, data requirements, and potential development scenarios are identified, after which the composition of the first working version is determined.
SaaS platforms
A SaaS platform provides users with functionality through a browser and typically supports registration, pricing plans, roles, payment, and account management. For such projects, stable operation with a large number of users, access control, and the ability to add new features without rebuilding the entire system are particularly important.
Custom web app development services for SaaS projects typically include interface design, backend, database, API, billing, and the admin area. If the product is developed using a subscription model, the architecture also needs to be prepared for expanding pricing plans, limits, and user scenarios.
Client accounts and portals
The client account gives the user access to personal data after authorization. It may contain requests, documents, invoices, payment history, order statuses, messages, settings, and other functions related to client service.
When developing a client account, access rights and data protection must be carefully considered. Users should see only the information they have access to, and company employees should be assigned their own roles for processing requests, changing statuses, and managing system content.
B2B portals
A B2B portal is suitable for companies that regularly work with dealers, suppliers, agents, or wholesale clients. This service allows you to accept orders, provide customized pricing, exchange documents, display stock levels, and manage settlements.
Web application development services for B2B projects often include integration with ERP or CRM, as the core data is already located in the company's internal systems. The web interface becomes an access point through which the partner receives up-to-date information without the need for a manager to perform each transaction.
Internal corporate systems
A corporate web application helps transfer internal processes from spreadsheets, correspondence, and individual services into a unified workspace. The system can distribute tasks, record approvals, store documents, collect reports, and manage the flow of operations.
Permissions are typically divided by department and job title, so role design is done before frontend development begins. Complex systems also consider activity logs, change histories, and access rules for specific types of information.
CRM, ERP and automation systems
A custom automation system is needed when a standard CRM or ERP doesn't cover a company's specific processes. Sometimes it makes more sense to retain the existing platform and develop a separate module that exchanges data with it via an API.
Custom web application development for such projects requires first defining data sources and synchronization procedures. If two systems can modify the same entity simultaneously, priorities, conflict handling, and information update rules must be defined in advance.
Marketplaces and eCommerce services
A marketplace involves more processes than a standard online store. In addition to a catalog and orders, it may also require seller accounts, commissions, moderation, payouts, inventory management, returns, and a complex status system.
In eCommerce projects, payment systems, delivery, analytics, and order processing reliability are of great importance. Public catalog pages also require special attention to SEO if organic search is to be a key customer acquisition channel.
Booking systems and online services
Booking services manage schedules, resource availability, and time slots. The system must prevent conflicting bookings, correctly account for cancellations, and synchronize changes between the client and administrative areas.
Additionally, you can enable online payments, notifications, and integration with internal accounting systems. For large numbers of branches, employees, or resources, booking rules are developed separately, as a simple calendar no longer covers the necessary scenarios.
Analytical systems and dashboards
The dashboard aggregates metrics from one or more sources and presents them in a clear interface. Users can filter data, compare periods, track KPIs, and obtain insights without manually preparing reports.
The complexity of a project depends on the volume of data and the frequency of metric updates. If information comes from CRM, advertising systems, financial accounting, and internal databases, it's necessary to determine in advance the procedure for loading, normalizing, and storing the data.
Mobile Web Apps and PWAs
Mobile web app development is suitable for projects where users often work from smartphones, but releasing separate apps for iOS and Android is not necessary. The interface opens via a browser and adapts to the screen size, preserving the service's core functionality.
A PWA can also support home screen installation, push notifications, and certain offline scenarios. The choice depends on the product's features, so a Progressive Web App shouldn't be used solely for the format's sake.
As an SEO specialist, I recommend establishing these requirements before starting frontend development. If public pages need to receive traffic from Google, I define indexable URLs, server-side rendering, canonical, sitemap, and multilingual rules in advance. Reworking the architecture after launch is usually more difficult than considering SEO during design.
Stages of developing a web application from scratch
You can commission web app development after a brief idea description, but an accurate estimate requires decomposition. Before programming begins, it's essential to understand the users, functions, roles, integrations, and limitations of the future product.
Sequencing the stages reduces the risk of complex requirements being discovered after the interface is ready. Individual stages can proceed in parallel if necessary, but key architectural decisions are made before the main development stage.
Analysis of the idea and business requirements
First, we define the problem the product solves and who will use it. The team analyzes the current process, existing systems, manual tasks, required features, and limitations.
At this stage, the composition of the MVP is also determined if the full product is too large for the first release. Features are divided into those critical to the launch and those that can be implemented after receiving feedback.
Preparing the technical specification
The terms of reference define functionality, user roles, scenarios, integrations, and data requirements. The more precisely the system's operating rules are described, the fewer disputes arise during implementation and acceptance.
The specifications can also include constraints, completion criteria, and environment specifics. The document is used by the development team and the client as a single point of agreement on project functions.
Prototyping
A prototype shows the interface structure before visual design and programming. At this stage, it's easier to change the user flow, remove unnecessary screens, or combine multiple operations into a single, clear flow.
User scenarios are tested against real product tasks. If a manager has to navigate through five screens to perform a simple task, it's cheaper to spot the problem in a prototype than after front-end development.
UX/UI design
Once the structure is agreed upon, the visual interface system is created. The designer works on pages, forms, tables, element states, errors, notifications, and mobile adaptation.
UX/UI should consider real data volumes, not just demo content. A three-row table may look neat in a mockup, but in a production system, it must remain usable even with hundreds of records and long values.
Frontend and backend development
The frontend team assembles the interface and connects it to the API, while the backend implements business logic and works with the database and external systems. Custom web application development requires constant synchronization between these components, as changes to the data model impact the interface and vice versa.
It's best to release features in small, complete blocks that can be tested before the entire project is completed. This process quickly identifies logic errors and reduces the amount of pre-release fixes.
Integrations
During the integration phase, the application connects to CRM, ERP, payment systems, delivery services, or other APIs. For each connection, authorization methods, available methods, request limits, and possible errors are checked.
Particular attention is paid to the exchange of critical data. If payment confirmations or orders are transferred between systems, reprocessing and protection against duplication must be provided.
QA and testing
QA verifies user scenarios, roles, forms, errors, and app behavior across different devices. Testing is conducted not only based on the "button press" principle, but also on the rules that determine the correct outcome of an operation.
Scenarios involving incorrect data, lack of access, and external service failures are tested separately. The user should receive a clear system response, and critical errors should be logged for further analysis.
Launching a web application
Before launch, production settings, domain, certificates, environment variables, databases, and integrations are checked. The production environment may differ from the development environment, so the final check is performed after the product is deployed.
The launch also includes monitoring of key user scenarios. Registration, authorization, payments, forms, and other critical operations must be performed through the application's live address.
Support and development
After launch, real data on how users interact with the product becomes available. This data can be used to modify scenarios, add features, optimize performance, and develop integrations.
Support also includes dependency updates, error monitoring, and infrastructure maintenance. If the product is in continuous development, these tasks are scheduled along with new releases.
What we actually did
Dental clinic · Kyiv and Chernihiv
+44% clicks from search
A domain with no history and a site on a website builder. We built the semantic core for the services and both cities, reworked the landing pages and built the link profile from zero. In four months: 34.8k clicks, impressions 1.32 → 1.76M, DR 0 → 41.
E-commerce · international
+96% clicks in two months
A catalog of digital 3D models. We clustered the semantics, rebuilt the hub pages and fixed duplicates and indexing errors. Google users 247 → 532, CTR 2.4% → 4%.
Medical center · Ukraine
+68.75% visibility in the first month
Narrow visibility and a small semantic core at the start. Semantics, landing page structure, metadata and internal linking, then gradual link building.
How long does it take to develop a web application?
The timeframe depends on the number of features, roles, integrations, and the readiness of the initial requirements. A small MVP and a corporate system with multiple departments differ not only in the amount of programming but also in the time required for analysis, approvals, and testing.
A web app development company can provide a realistic timeline after decomposition. The more unknowns remain before work begins, the higher the risk of revising the initial estimate.
Instead of a universal timeline, it is convenient to divide projects into several levels:
| Project type | What usually affects the timeline |
|---|---|
| MVP | Core user scenarios, one key business model, limited set of integrations |
| Medium-complexity application | Multiple roles, admin area, integrations, reports and complex logic |
| SaaS or enterprise system | A large number of modules, data, roles, integrations, load and security requirements |
The exact weeks or months are determined after assessing the specific project. If some requirements are still unknown, it is advisable to first conduct a separate analysis phase.
How much does it cost to develop a web application?
The price of web application development is calculated individually and can vary significantly even for projects with similar descriptions. A user account with multiple roles and an existing CRM requires one scope of work, while a SaaS with billing, analytics, and dozens of integrations requires another.
Therefore, a fixed price without requirements tells the client little. For a preliminary estimate, it's sufficient to describe the key features, users, and systems the app needs to interact with.
What does the price depend on?
The cost consists of analysis, design, frontend, backend, testing, and infrastructure work. The more non-standard rules and integrations a project contains, the more time it takes to implement and test.
The estimate is usually influenced by:
- the number of user roles and the differences between their work scenarios;
- volume of interfaces, forms, tables, reports and administrative functions;
- complexity of backend logic and the number of related business processes;
- external APIs, CRM, ERP, payments and other integrations;
- requirements for service performance, security and availability;
- the need for PWA, multilingualism, SEO, and a complex public part;
- volume of QA, documentation and further technical support.
After decomposition, it becomes clear which functions make up the bulk of the budget. This allows for the first version to be trimmed without accidentally removing critical scenarios.
How is the project cost calculated?
The first estimate is based on functional blocks. The team estimates analysis, design, development, integration, testing, and infrastructure, after which the client receives a clear project structure.
If your budget is limited, you can create an MVP and move some features to future releases. This approach provides a more accurate basis for decision-making than trying to order a web app at a fixed price without clearly defined requirements.
Why order web application development from Seo-Gen?
Seo-Gen designs the application around specific processes and selects technologies after analyzing the task. Before the main development begins, roles, user scenarios, integrations, and requirements for the public-facing portion of the product are defined.
If an app is expected to receive organic traffic, SEO is considered alongside its architecture. For indexed pages, SSR, URLs, metadata, canonical, sitemap, hreflang, and other technical elements are carefully considered in advance.
Custom web application development is carried out through a controlled change process. Code is committed to Git, new features are tested before production, and critical scenarios are further tested on the production domain after release.
For English-language projects, the same approach applies to web app development companies, web application development companies, and custom web application development tasks. Terminology varies depending on the market, but requirements for data, stability, architecture, and support remain part of the same engineering process.
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Answers to your questions
How much does it cost to develop a web application?
The cost depends on functionality, architecture, number of roles, design, integrations, security requirements, and testing volume. For a preliminary estimate, simply describe the users, key operations, and systems with which the application must exchange data.
The exact cost is calculated after the features are decomposed. If the full project exceeds the available budget, an MVP can be separated out and additional modules moved to later releases.
How long does it take to develop a web application?
The duration depends on the complexity of the product and the maturity of the requirements. A project with a single core scenario typically requires fewer approval stages than an enterprise system with many roles, integrations, and related processes.
The timeline is estimated after evaluating individual functional blocks. This approach yields a more reliable result than a one-size-fits-all figure for all projects.
Is it possible to develop a web application from scratch to suit our business processes?
Yes, custom web application development is used specifically for tasks where ready-made services don't fit a company's existing processes. Before starting work, it's necessary to describe the current workflow and determine which operations need to be automated.
After analysis, user scenarios, roles, and integrations are developed. This data becomes the basis for the technical specifications and architecture of the future product.
Is it possible to integrate a web application with a CRM or ERP?
Integration is possible if the CRM or ERP provides an API or other supported data exchange method. The connection can transfer clients, orders, documents, stock levels, statuses, and other information.
Before development, the documentation for a specific system is reviewed. It is also determined which side is considered the primary data source and how the application should handle synchronization errors.
How is a web application different from a mobile application?
The web app opens through a browser and can be used on a computer, tablet, or smartphone without requiring separate installation from an app store. A native app is installed on the device and gains deeper access to the mobile operating system's capabilities.
The choice depends on the product scenario. For SaaS, user accounts, B2B systems, and most internal services, a browser interface is often sufficient.
Is it possible to make a web application smartphone-friendly?
Yes, the interface is designed to be responsive and tested on mobile screens. Forms, tables, menus, and other elements are rearranged to allow users to perform basic actions on a small screen.
If additional mobile functionality is required, a PWA is considered. The decision is made after verifying specific requirements, as browser capabilities differ from native apps.
Is it possible to start with an MVP?
Yes, an MVP helps launch key features earlier and test the product with real users. At the start, a minimal scenario is defined, without which the service will not be able to fulfill its core purpose.
After launch, functionality is expanded in stages. The core architecture is designed with future development in mind, ensuring that new modules don't require constant reworking of the product's foundation.
Will the web application be indexed by Google?
Google may index an app's public pages if they are accessible to the search engine and technically implemented correctly. Private accounts and user personal data are generally excluded from search indexing.
For open pages, SSR, URL, Title, Description, Canonical, Robots, Sitemap, and other SEO tools are planned in advance. After launch, the final result is verified using real server responses and the markup available to the search crawler.
Web application development begins with a clear goal, users, and business processes, and then the technologies and feature set are selected. This process helps to more accurately evaluate the project, prepare an MVP if necessary, and lay the groundwork for further development.
To get a preliminary estimate, prepare a brief product description, key user roles, required features, and a list of integrations. This will be enough to determine the next step and estimate the cost of developing a web app for your project.
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More on: Web application development
How is a web application different from a regular website?
A website is more often used to publish information and attract visitors, whereas a web application requires continuous interaction with data and business logic. Users can log in, perform operations, change information, receive personalized results, and interact with the system over an extended period of time.
The distinction is gradually blurring, as large websites also include interactive features. Therefore, when choosing a technology, it's more appropriate to consider user scenarios, data requirements, and the amount of server-side logic.
Web application and website
This comparison helps determine whether a dedicated web application development company is needed or whether the task can be accomplished within a standard website. If the project consists primarily of information pages and a few forms, a full-fledged web application architecture may be overkill.
| Criterion | Regular website | Web application |
|---|---|---|
| The main task | Publishing and receiving information | User interaction with data and functions |
| Authorization | May be absent | Often part of core scenarios |
| Business logic | Usually limited | May involve complex rules and processes |
| Personalization | Little or none | Depends on account, role and data |
| Integrations | Forms, analytics, CRM | CRM, ERP, payments, API, internal systems |
| Development | New pages and content | New features, modules and user scenarios |
When designing, you can combine both approaches. The public area is responsible for information and search traffic, while the authorized area functions as a full-fledged application.
Web application and mobile application
A native mobile app is installed on a device and developed for a specific operating system. A web app runs through a browser, so a single interface can be used on a computer, tablet, and smartphone without publishing each version through an app store.
The difference affects the budget and capabilities of the product. If the service requires constant access to specific phone functions or complex offline logic, native development may be justified.
When to choose a web application?
A web app is suitable for SaaS, B2B portals, user accounts, internal systems, CRM, and most services where the primary work is data-driven. Users simply open the link and log in to their account, making it easier to centrally manage product launches and updates.
A web app development company can maintain a single codebase for different devices if the product doesn't require deep integration with the mobile OS. This approach reduces the amount of parallel development and simplifies the release of updates.
When is a native mobile app better?
A native approach is considered when a product actively utilizes device features, must operate reliably offline, or requires capabilities that a browser provides with limitations. The decision is made based on an analysis of specific scenarios, not solely on the popularity of mobile apps.
Some products use two interfaces: a web app for day-to-day work and a mobile app for specific scenarios. A common backend and API can serve both client-side components.
How is a web application structured?
Most web applications can be divided into a client-side component, server-side logic, and a data storage layer. Between them, an API operates, through which the interface sends requests and receives results for a specific user.
The simplified diagram looks like this:
User → Frontend → API → Backend → Database↘CRM / ERP / payment systems / external services
The specific architecture depends on the workload, functionality, and reliability requirements. A simple MVP and a large SaaS platform typically require different approaches to infrastructure.
Frontend
The frontend is responsible for everything the user interacts with: pages, forms, tables, filters, menus, notifications, and interface states. Development takes into account user scenarios, responsiveness, loading speed, and correct display across different devices.
Projects can use React, Next.js, JavaScript, and TypeScript. The choice depends on the architecture and requirements, so the specific technology is determined after product analysis rather than pre-selected for every project.
Backend
The backend processes data and executes server-side business logic. It checks user permissions, performs calculations, creates and modifies records, interacts with external APIs, and returns to the frontend only the results permitted by the current role.
For the server side, we use Node.js, PHP, Python, .NET, and other technologies. The choice depends on the existing infrastructure, workload, integration requirements, and the expertise of the team supporting the project.
Database
A database stores users, orders, documents, settings, transactions, and other structured information. When designing a database, it's important to define the relationships between entities, the order in which records are updated, and backup requirements.
Depending on the data structure, PostgreSQL, MySQL, MongoDB, and other systems are used. The choice of database should take into account the actual needs of the application, as replacing the storage after the launch of a large project may require significant changes.
API and external integrations
The API connects the frontend with the backend and facilitates the exchange of information with external services. Through API integration, an application can retrieve clients from a CRM, transfer orders to an ERP, process payments, or obtain delivery status.
Integrations require checking the third-party system's documentation, request limits, and authorization rules. If the external service is temporarily unavailable, the application must handle the error gracefully and avoid losing user data.
SPA, MPA, and PWA – which architecture to choose?
SPAs, MPAs, and PWAs solve different problems, so there's no one-size-fits-all solution for all projects. The architecture is selected based on the interface, indexing, number of public pages, mobile scenarios, and user interaction speed requirements.
It's a mistake to choose an SPA just because the app needs to look modern, or a PWA just because it can be installed as a shortcut on a smartphone. Each format should provide practical value to the specific product.
SPA – Single Page Application
A Single Page Application loads the main application shell, after which individual parts of the interface are updated without a full document reload. This approach is convenient for systems where the user spends long periods of time working within a single interface and performing multiple sequential operations.
SPAs are often used for CRM, analytics dashboards, user accounts, and internal applications. For public pages, indexing and content delivery to search engines require special consideration.
When is a SPA appropriate?
SPAs are well-suited for interfaces with a large number of dynamic actions, filters, tables, and forms. Users can switch between sections without waiting for each new page to fully load if the architecture and API are designed correctly.
However, an app shouldn't be judged solely by its smooth interface. It's also important to consider the SEO of the public part, initial loading, error handling, and requirements for running on low-end devices.
MPA – Multi Page Application
A Multi-Page Application consists of individual pages that the server returns when the user navigates. This approach remains convenient for projects with large amounts of publicly indexed content and a clear URL structure.
MPA can be combined with modern interactive components, so this format doesn't mean abandoning a dynamic interface. The architecture is chosen at the product level, and individual features can work without a full page reload.
When is MPA appropriate?
MPA is suitable for services where search indexing of a large number of pages plays a significant role. This category includes catalogs, marketplaces, content platforms, and projects with a complex open structure.
When implemented correctly, each page has its own URL, meta tags, and server response. This simplifies monitoring the indexed portion of the project and managing search landing pages.
PWA – Progressive Web App
A Progressive Web App leverages the browser's capabilities for scenarios that partially resemble a mobile app. Users can add a service to the home screen, and some features can work over unstable connections or utilize push notifications.
A PWA makes sense if the audience truly needs such features. For a typical corporate account, an additional layer of technology may not provide significant benefits, so the decision is made after analyzing product usage.
When should you choose a PWA?
PWAs are suitable for services with a large mobile audience that need quick repeat access via smartphone. This format can be useful for delivery, booking, eCommerce, and other products that users return to regularly.
When choosing, the limitations of browsers and mobile platforms are taken into account. PWAs have different capabilities than native apps, so requirements for notifications, offline mode, and device features are verified before development.
Web application development technologies
The technology stack is determined once the architecture, workload, integrations, and support requirements are understood. Using a popular framework alone won't make a product faster or more reliable if it's not suited to the specific task.
A web application development company must also consider future system maintenance. Over the next few years, the project will require updates, new features, and technical debt management, so the stack must remain maintainable and understandable to the team.
Frontend technologies
React, Next.js, JavaScript, and TypeScript can be used for the frontend. React is convenient for component-based interfaces, and Next.js offers additional capabilities for server-side rendering and building public pages, if the project requires these.
The choice is based on the app's size, interaction patterns, and SEO requirements. A simple administrative interface and a large public service may use different rendering schemes, even within the same tech stack.
Backend technologies
The backend can be built on Node.js, PHP, Python, .NET, or another suitable stack. The main criteria are performance, integrations, security, the client's existing infrastructure, and the availability of specialists for ongoing support.
It's more important to choose a clear module architecture and rules for component interaction than to assemble the maximum number of technologies. The more complex the system, the more expensive it is to test, update, and maintain.
Databases
PostgreSQL is often used for structured data and complex relationships between entities, while MongoDB is suitable for specific document-based storage scenarios. MySQL also remains a popular choice for web projects.
The decision is made after analyzing the application's data and queries. Indexes, backups, migrations, and system behavior as the volume of data increases must be considered in advance.
Cloud and DevOps
The infrastructure includes servers, containerization, deployment, backups, and monitoring. Docker helps reproduce the same environment at different stages of development, and CI/CD automates part of the build and update release processes.
DevOps processes are especially important for a product that is constantly evolving. The team must understand which version is running in production, which changes are being tested, and how to restore a stable state after a failed release.
How do we organize the development and release of updates?
Product stability depends not only on the code written, but also on the release process. Changes must be recorded, tested, and only then pushed into production.
This process is especially important for apps with real users, payments, orders, or business data. A production error can impact the company's operations, so the release process can't be built on manual edits without a history.
Git and revision history
The project's code is stored in Git, where changes and their authorship are recorded. The team can see what was changed, when a specific change was made, and which version they can revert to if needed.
History also simplifies collaboration among multiple developers. Changes can be reviewed before merging into the main branch, and contentious code fragments remain linked to the specific task.
Dev → check → Production
New features and fixes are first implemented in the development or testing environment. There, the team runs through key scenarios and checks the compatibility of the changes with existing functionality.
After review, the finalized version is pushed to production. This process reduces the likelihood of an unreviewed change immediately impacting users or production data.
Post-release testing
Even a successfully tested change is verified through the production domain after publishing. Production environments, integrations, caching, and infrastructure settings may differ, so verifying it on the dev domain alone is not enough.
A short set of mandatory scenarios is compiled for critical functions. This helps quickly ensure that the release does not disrupt authorization, forms, payments, and other key operations.
SEO for web applications
Not every part of an app requires SEO. A private user account typically shouldn't be indexed, while public pages for services, categories, products, or content can attract organic traffic.
Therefore, search visibility requirements are determined during the architecture design. If the indexed portion is added later, it may be necessary to change the routing, rendering method, and URL structure.
SSR and indexed pages
SSR delivers a completed HTML page to the search robot, containing content generated by the server before executing client-side JavaScript. This approach is useful for public pages where predictable indexing and accurate metadata transfer are important.
An SPA can also have an indexable public section, but the rendering method needs to be thought out in advance. In some projects, it's convenient to combine server-side rendering of public pages with client-side logic within the authorized zone.
What is built in for SEO?
The public portion must return clear URLs, correct HTTP statuses, and its own metadata. For a multilingual project, hreflang, canonical, and separate language versions of the content are also taken into account.
The following elements are checked for indexed pages:
- SSR or another approach where the search engine gets the required page content;
- unique Title, Description and headings for standalone search landing pages;
- canonical, meta robots and correct handling of URL duplicates;
- sitemap, hreflang and language versions for multilingual projects;
- Schema.org structured data where it matches visible content;
- loading speed, Core Web Vitals, and the absence of critical rendering errors.
After launch, the public portion is tested using real URLs. In-app configuration alone is insufficient if the final server response or page markup differs from the expected result.
Integrating a web application with other systems
Most business applications don't operate in isolation. Customers may already be in a CRM, orders in an ERP, payments in a payment provider, and documents in a company's internal service.
Custom web application development must consider these relationships before creating the data model. If integrations are added only at the end, the existing application structure may not align well with external system formats.
CRM and ERP
CRM integration allows you to transfer customers, requests, deals, and statuses between the web application and the sales system. The ERP can be used for stock levels, orders, documents, financial data, and other internal operations.
Exchange can be one-way or two-way. Before development, it's determined which system is considered the primary source of specific data and what happens when a single record is modified simultaneously in multiple locations.
Payment systems
Payment integration is responsible for creating payments, receiving transaction results, refunds, and recording statuses. Critical operations should be verified on the backend, not just by the message the user sees in the browser.
The design also takes into account repeated payment service notifications and situations where the user closes the page before completing the transaction. The final order status should depend on the payment system's confirmed data.
Third-party APIs
An external API can transmit exchange rates, shipping data, documents, messages, or information from a partner system. Available methods, limits, response formats, and authorization rules are checked before integration.
If a third-party service is temporarily unavailable, the application must maintain predictable behavior. Queues, retries, and error logging can be used for critical operations.
Mail and notifications
Email is used for registration confirmation, access restoration, order notifications, and other events. In some projects, it is supplemented by system notifications, Telegram, or other agreed-upon communication channels.
It's best to keep message templates separate from the application's business logic. This simplifies multilingual support, text editing, and support for different notification types without changing the core code.
Web Application Security and Scaling
Security requirements depend on the data and product functions. A service with a public catalog, an internal employee portal, and a financial system all have different risk levels, so a single set of measures cannot be applied to all projects.
The architecture should also take into account the expected increase in load. It's cheaper to plan for scaling in advance than to urgently rebuild the product after a sharp increase in user numbers.
Authorization and user roles
After logging in, the system determines not only the user's identity but also their permissions. A client, manager, and administrator may work with the same entity but see different fields and perform different actions.
Permissions verification should be performed on the backend. Hiding the button in the interface improves the user experience, but in itself does not protect data from API requests.
Data protection
Security design includes access control, secure storage of credentials, incoming data validation, and protection of critical operations. Specific measures are determined after analyzing the architecture and information types.
Absolute protection against all threats cannot be promised. The practical task is to mitigate risks, update dependencies promptly, monitor for errors, and fix any vulnerabilities discovered.
Scaling
The system must accommodate the growth in the number of users, transactions, and stored information. Sometimes, increasing server resources is sufficient, while in other cases, load balancing between individual components is necessary.
Modular architecture helps develop a large product, but breaking a small application into multiple services can only increase complexity. The decision is made based on the expected workload and development plans.
Performance
Application speed depends on the frontend, backend, database, and external integrations. A slow database or third-party API query can't be fixed by interface optimization alone.
Monitoring, logging, and operation execution time measurements are used to identify bottlenecks. Queries, caching, and infrastructure are then optimized specifically where the confirmed problem exists.
MVP or a full-fledged product right away?
An MVP is used to launch a minimal version of a product that already solves a key user problem. This format helps validate a hypothesis and obtain real-world data before developing a large number of additional features.
However, an MVP doesn't mean low-quality temporary code. If the product is going to be developed further, the core decisions regarding data, security, and architecture must be taken into account for future releases.
What is included in an MVP?
The MVP includes features essential for the user to complete the core scenario. For a booking service, this could include selecting a time slot, creating a booking, and managing it, while additional reports or a complex loyalty program will come later.
The composition of the first version is determined by priorities. Each feature is assessed based on its impact on the product's operation, rather than by the desire to immediately implement all the capabilities of the future system.
When is an MVP more cost-effective?
An MVP is suitable for startups, new SaaS products, and internal systems where some requirements will only become clear after use. An MVP allows you to test scenarios in practice and determine which features are truly in demand.
This approach also reduces the amount of guesswork at the start of a project. Instead of spending time developing a full version, the team receives feedback and uses it when planning future releases.
How does an app evolve after MVP?
After launch, errors, user requests, and real-world scenarios are analyzed. New features are added based on priority, and existing processes are adjusted if practice deviates from initial assumptions.
The architecture must support the product's evolution. If the first version was designed as a one-off prototype, expansion may require significant refactoring.
What does the customer receive after launch?
The project delivers a working web application with agreed-upon functionality, rather than a collection of separate mockups and source files. The deliverable includes the components identified during the assessment phase and specified in the project agreements.
Depending on the task, the customer receives:
- responsive frontend with implemented user scenarios and interface states;
- backend with business logic, authorization, roles and processing of necessary operations;
- database and configured work with the main entities of the project;
- agreed integrations with CRM, ERP, payment services or other APIs;
- a working server environment and a prepared update release procedure;
- repository or other agreed upon arrangement for accessing source code;
- technical documentation and support, if included in the project.
After launch, the product can be developed in separate releases. New functionality undergoes the same development and testing cycle to ensure changes do not disrupt existing user experiences.