API Development Services preview

API Development Services

Connect your systems. Ship integrations faster. Keep your data secure.

We design, develop, and integrate REST and GraphQL APIs that link your products, internal databases, and the third-party services your business depends on. We've shipped production APIs for various industries and software teams.

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Challenges we solve

Number 1

Integrations that break whenever something changes?

Point-to-point connections between systems multiply fast. One vendor renames a field, and three internal tools stop syncing. To prevent cascading outages, strict versioning, clear schema contracts, and backward compatibility are built into our API designs.

Number 2

Aging SOAP services and undocumented internal APIs?

Many companies run critical operations on APIs written years ago, with no documentation and the original authors long gone. We map the existing behavior, rebuild the interface on a modern stack, and migrate consumers across without interrupting service.

Number 3

Sensitive data moving through unprotected endpoints?

Endpoints exposing patient records, payment details, or account data are prime targets. Securing these assets requires robust authentication, fine-grained authorization, strict rate limiting, and end-to-end encryption to validate and protect every payload.

Number 4

Slow responses once real traffic arrives?

APIs that perform fine in a demo can fall over during a launch or a seasonal peak. We profile query patterns, add caching where it counts, paginate heavy responses, and design for horizontal scaling so throughput holds when usage spikes.

Number 5

Frontend teams blocked waiting on backend changes?

Product velocity plummets when every new screen requires a custom endpoint. GraphQL eliminates backend round-trips by letting client teams fetch precisely what a view needs, while our REST architectures focus entirely on resource-oriented and client-friendly consumption.

Number 6

Third-party services that are painful to connect to?

Payment processors, CRMs, ERPs, and shipping carriers each come with their own auth flows, quirks, and failure modes. We build integration layers that handle retries, webhooks, idempotency, and error recovery, so a flaky upstream service doesn't corrupt your data.

API development services

We provide full-cycle API development services. Our custom software development services cover architecture, implementation, testing, documentation, deployment, and ongoing maintenance. Every API we ship is documented, tested, and built to survive contact with production traffic.

API development services preview

Custom API development

Instead of forcing your business logic into a rigid, off-the-shelf model, custom endpoints adapt to your actual operations. This process starts with designing a tailored resource model and defining a contract that perfectly mirrors your product and data workflows.

REST API development

Predictable behavior, consistent error handling, and clear versioning are the cornerstones of successful REST architectures. Adhering to established conventions ensures that internal teams and external partners can adopt the interface smoothly.

GraphQL API development

Enabling client applications to fetch exact datasets in a single request improves frontend performance. As the graph grows, maintaining speed and safety requires rigorous resolver optimization, query-depth limiting, and strict schema governance.

API integration services

Keeping information consistent across payment gateways, CRMs, ERPs, cloud services, and IoT devices demands a unified approach. Seamless synchronization is achieved through expertly managed authentication and precise data mapping between dependent systems.

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Blockchain API development

Connecting applications to blockchain networks doesn’t have to mean running proprietary nodes. Through CryptoAPI, dApps gain a single, structured interface to Ethereum, Bitcoin, and other chains, receiving on-chain events instantly via WebSockets and webhooks.

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API security and testing

Before real users ever touch an endpoint, it must be hardened against abuse. Thorough functional, load, and security testing, combined with robust authentication and rate limiting, guarantees that vulnerabilities are caught long before deployment.

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Success stories

We've built and integrated APIs that businesses and their partners rely on in production every day.

API-first KYC platform on Canton Network

For FiveNorth, PixelPlex built 5N ID, a unified KYC platform on the Canton Network built around an API-first design. A single comprehensive API lets any project or dApp add compliant, enterprise-grade identity verification without building it in-house.

  • API integration in days
  • Sumsub integration handling one-time KYC verification
  • Consent-based data sharing enforced by Daml smart contracts
  • Up to 60% lower drop-off during signup
  • Delivered from first consultation to MVP in 2.5 months
API-first KYC platform on Canton Network case preview

Actionable data explorer and API for Canton Network

    FinTech
  • Canton Network
  • Indexer API
  • On-chain data
  • Featured App

CC View is a high-performance data engine and developer-first API that transforms raw protocol data into a streamlined, institutional-grade asset. It provides the data layer for wallets, trading desks, and institutional-grade dApps.

  • Structured API endpoints
  • Live alerts via webhooks
  • $85k saved in initial build costs
  • 100% success rate across 6.05M+ total requests
  • Initial development completed in 1.5 months
Actionable data explorer and API for Canton Network case preview

Payment and loyalty integration for a grocery delivery app

PixelPlex built a cross-platform delivery app for 15,000+ SKUs and connected it to the systems behind it. We integrated the bank's payment API with a hold-and-adjust flow that updates the charge when an out-of-stock item is swapped.

  • Bank payment API integration
  • One-click card payments
  • Two-way sync with the retailer's loyalty-card program
  • OneSignal push notifications
  • One backend for the mobile app and admin panels
Payment and loyalty integration for a grocery delivery app case preview

Health record aggregation app

PixelPlex built a mobile app that pulls a user's medical records from many separate providers into one view. We built a data-aggregation layer gated behind identity verification and consent, integrated Apple Watch and Fitbit, and connected the app to the PTOYMatrix blockchain and Ethereum wallets.

  • Data-aggregation layer
  • Apple Watch and Fitbit integration
  • Blockchain and Ethereum-wallet integration
  • Insurance integration for one-time care-plan payments
  • HIPAA compliance work and IT risk assessment
Health record aggregation app case preview

IoT data pipeline for BMW dealer showrooms

    IoT
  • Enterprise
  • Data
    • AI
  • Web & mobile

The software collects and stores data from iBeacon sensors, processes it with analytics and AI to produce visitor heat maps and statistics, and serves real-time data to a manager web dashboard and a customer mobile app.

  • Collecting data from iBeacon sensors
  • Analytics and AI generating heat maps
  • Real-time data served to a web dashboard
  • Mobile app for visitors and existing car owners
  • Booking, history, and notifications for owners
IoT data pipeline for BMW dealer showrooms case preview

Why choose PixelPlex

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Engineering depth across the full stack

We've been building software for more than 17 years, across backend systems, web and mobile apps, data platforms, and blockchain. An API is rarely an isolated piece, and we understand the systems on both sides of it.

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Security as a default

We build authentication, authorization, rate limiting, and validation into the API at the design stage, and we test the way an attacker would. For regulated clients, we design with the relevant compliance requirements in mind.

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Architecture built to scale

We design APIs that hold up under growth, with caching, pagination, and horizontal scaling considered up front. We'd rather plan for the traffic you'll have in two years than rewrite it under pressure.

17+

Years of experience in blockchain and Web3

3Unicorn icon

Unicorns transformed their domains right from the start

10M+

Users scaled in the first 18 months

1M+

Secure smart contract executions facilitated

450+

Projects completed

50M

Happy users for our clients

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    Top Clutch Blockchain Company New York City 2026

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    Top Clutch IT Services Company Gaming 2026

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    Top Clutch Smart Contract Development Company New York City 2026

  • clutch badge

    Top Clutch Identity and Access Management New York City 2026

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    Top Clutch Web3 Development Warsaw 2026

Benefits of custom API development services

1.

Faster integrations

A well-designed API turns a months-long integration project into a predictable task. New partners, internal tools, and acquired systems connect through a documented interface instead of one-off custom work each time.

2.

Cleaner data flow

APIs give your systems an agreed way to exchange information. Instead of nightly exports and manual reconciliation, data moves between your CRM, billing, and analytics in near real time, with a clear record of what was sent.

3.

Room to scale

Decoupling your frontend, backend, and integrations through APIs lets you scale each part independently. A traffic surge on your customer app no longer means touching your internal systems.

4.

New products on existing infrastructure

Once your core capabilities are exposed as APIs, building a mobile app, a partner portal, or an automated workflow on top of them becomes a much smaller effort. The hard work of business logic is already done and reusable.

5.

Less vendor lock-in

An integration layer between your platform and third-party tools means swapping a payment processor or CRM is a contained change rather than a rewrite. Your business logic stays put while the external dependency changes behind the interface.

Cost of API development

Starting at

$20,000

Cost scales with the number of systems you connect, the complexity of your business logic, and the security and compliance work your industry requires. We give a scoped estimate after discovery.

What's included:

  • API architecture and contract design
  • Endpoint development with error handling and logging
  • Unit, integration, and load testing
  • Reference documentation and an integration guide

Building a platform API with multiple third-party integrations, a GraphQL layer, or regulated-data requirements such as PCI DSS or HIPAA? We'll scope the work and give you a precise estimate.

API development across industries

What makes an API work well changes from one sector to the next. The constraints a payment system faces have little in common with those of a logistics network, so we shape each integration around the realities of your industry.

FinTech and trading

Fast, consistent data exchange is the lifeblood of fintech, often requiring hundreds of calls per second. Delivering low-latency market data means streaming via WebSockets while maintaining an immutable audit log for every transaction.

  • Low-latency market data and order APIs
  • Real-time streaming over WebSocket and webhooks
  • Audit logging and access control on every endpoint
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FinTech and trading

Healthcare and bioinformatics

Moving sensitive medical records across clinics and labs places privacy above all else. HL7 and FHIR integrations are designed to protect data at every hop while connecting smoothly with the EMR and imaging systems clinicians already rely on.

  • HL7 and FHIR API development and integration
  • Connections to EMR, lab, and imaging systems
  • HIPAA-aware authentication and consent handling
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Healthcare and bioinformatics

Logistics and supply chain

Modern logistics depends on a constant flow of near-real-time data from vehicles and warehouses. By utilizing event-driven webhooks and telemetry APIs, clean information is routed directly to the systems that need to act on it.

  • Real-time tracking and telemetry APIs
  • Event-driven webhooks for shipment updates
  • Integration across carrier and warehouse systems
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Logistics and supply chain

Retail and eCommerce

Storefronts, inventory, and payment gateways must communicate instantly, especially during massive traffic spikes. Syncing catalogs and stock across web and mobile channels guarantees a high-speed checkout experience.

  • Product, cart, and order APIs for web and mobile
  • Payment gateway and checkout integration
  • Inventory sync across stores and marketplaces
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Retail and eCommerce

Banking

Bridging modern applications with core banking infrastructure requires highly secure, compliant interfaces. Open banking and partner integrations are deployed with strong authentication protocols to ensure daily operations remain completely undisrupted.

  • Open banking and account-information APIs
  • Secure API layers over legacy core systems
  • Partner integration with strong authentication
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Banking

Payment

Because financial gateways operate around the clock, dropped transactions or missed fraud signals are unacceptable. High-availability interfaces ensure clean reconciliation and fail-proof webhook handling for processors and card rails.

  • Integration with payment processors and card rails
  • Idempotent transaction and refund APIs
  • Webhook handling for settlement and fraud events
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Payment

Lending

Approving a loan in seconds requires pulling credit, identity, and banking data instantly. The entire lifecycle is kept in perfect sync through tightly integrated underwriting and payment rail APIs.

  • Credit bureau and KYC/identity API integration
  • Underwriting and loan-origination system APIs
  • Disbursement and repayment via payment rails
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Lending

Education

Scaling learning platforms to accommodate massive waves of new students requires a multi-tenant approach. Institutional systems, LMS platforms, and assessment tools are unified via LTI integrations and content delivery pipelines.

  • Multi-tenant APIs for institutions and cohorts
  • LMS and assessment tool integration via LTI
  • Content delivery and progress-tracking APIs
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Education

Real estate

Property markets generate fragmented data across listings, valuations, and geospatial feeds. Aggregating these disparate sources into a single API empowers users with lightning-fast search and highly accurate market analytics.

  • Listing and market-feed aggregation APIs
  • Geospatial search and mapping integration
  • Valuation and analytics data services
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Real estate

Oil and gas

Remote energy operations produce overwhelming volumes of constant equipment telemetry. Ingesting this data at scale transforms raw metrics into actionable insights for safety monitoring, maintenance forecasting, and edge connectivity.

  • High-volume telemetry ingestion APIs
  • Edge and remote-site data connectivity
  • Integration with monitoring and forecasting tools
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Oil and gas

Construction

Job sites run smoothly only when planning, procurement, and field tools share the same reality. Project tracking APIs connect the office and the field, ensuring every team works from consistent data.

  • Project and resource-tracking APIs
  • Integration across planning and procurement tools
  • Field-to-office data sync across job sites
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Construction

Insurance

Complex underwriting and claims rely on mountains of historical policy data. Modernized interfaces connect legacy systems directly to advanced rating and modeling engines to power accurate pricing and fraud detection analytics.

  • Policy and claims data APIs
  • Integration with rating and modeling engines
  • Modernized interfaces over legacy policy systems
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Insurance

Fitness

High-volume streams from wearables and smartphones demand immediate backend responses. Processing continuous device data enables real-time metric dashboards and integration with platforms like Apple Health and Google Fit.

  • Wearable and device-data ingestion APIs
  • Real-time metric and dashboard APIs
  • Integration with Apple Health, Google Fit, and trackers
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Fitness

Restaurant

Franchise operations depend on interconnected systems to keep locations aligned. Service-based APIs orchestrate ordering, inventory, and POS development services, ensuring that an isolated menu outage never paralyzes the broader network.

  • Ordering and menu APIs across locations
  • POS and inventory-system integration
  • Delivery-platform and aggregator integration
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Restaurant

Travel

Managing live inventory, dynamic pricing, and reservations means keeping countless supplier systems perfectly synced. Robust orchestration handles booking flows and stabilizes data across GDS providers, even during massive seasonal demand spikes.

  • Booking and reservation APIs for live inventory
  • Orchestration across travel-supplier and GDS APIs
  • Caching and scaling for seasonal demand
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Travel

Entertainment

Live events, ticket drops, and new content releases trigger massive, sudden traffic surges. Streaming, ticketing, and subscription APIs are engineered to maintain seamless user access and payment processing under extreme load.

  • Content access and streaming APIs
  • Subscription and payment integration
  • Ticketing and access-control APIs
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Entertainment

API development process

Discovery and API strategy

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Architecture and contract design

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Development

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Testing and security review

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Documentation and developer onboarding

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Deployment, monitoring, and support

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Discovery and API strategy

Every successful integration begins with mapping the involved systems, datasets, and end-consumers. Before a single line of code is written, usage standards are agreed upon, and the optimal architecture (REST or GraphQL) is selected based on your specific use case.

Deliverables

  • API requirements document
  • Technology recommendation
  • Integration map

Architecture and contract design

Establishing a stable agreement allows frontend and backend teams to work in parallel without friction. This phase locks down the API contract, clearly specifying endpoints, schemas, authentication models, error formats, and versioning strategies.

Deliverables

  • OpenAPI or GraphQL schema
  • Authentication design
  • Data model

Development

Transforming the agreed-upon contract into a functional system involves implementing core business logic and integration pipelines. Consistent error handling and comprehensive logging are woven into the endpoints from the beginning.

Deliverables

  • Working API
  • Source repository
  • Inline code documentation

Testing and security review

Validating performance under realistic traffic is crucial for a production-ready release. The API undergoes rigorous unit, integration, and load testing, alongside a thorough security audit to expose vulnerabilities like broken authentication or excessive data exposure.

Deliverables

  • Test suite and coverage report
  • Load test results
  • Security review findings

Documentation and developer onboarding

Integrating a new system shouldn’t require constant hand-holding. Comprehensive reference materials, practical request/response examples, and clear getting-started guides are treated as core deliverables to empower your internal teams and external partners.

Deliverables

  • API reference
  • Integration guide
  • Example requests

Deployment, monitoring, and support

Launching the API is just the beginning of its lifecycle. Once deployed alongside monitoring dashboards and alerting tools, an ongoing support framework ensures seamless dependency updates, endpoint additions, and future versioning as your product evolves.

Deliverables

  • Deployment pipeline
  • Monitoring dashboards
  • Maintenance plan

Our signature domains

An API is usually the front door to something larger. These are the deeper domains we build behind that door and connect to through the same APIs we design for you.

Blockchain

Connecting applications to decentralized networks is streamlined through CryptoAPI, eliminating the need to manage proprietary nodes. On-chain events, smart contract data, and transaction balances are pushed directly to your product via WebSockets and webhooks.
Explore blockchain development servicesmore-content
Blockchain domain background

Tokenization

Issuing and managing tokenized assets requires complex on-chain logic for wallets, compliance, and transfers. Documented, access-controlled endpoints allow your internal systems and partners to interact safely with digital assets, NFTs, and carbon credits.
Explore tokenization servicesmore-content
Tokenization domain background

Data science

Relying on ad-hoc exports limits your product's potential. By establishing robust data pipelines and warehouses, a consistent analytics layer is exposed through queryable APIs, driving powerful reporting and visualization features directly within your applications.
Explore data science development servicesmore-content
Data science domain background

Machine learning

Advanced AI capabilities, such as fraud scoring, computer vision, and document processing, can function exactly like standard service endpoints. Deploying custom ML models behind real-time APIs allows your applications to seamlessly consume powerful, generative insights.
Explore machine learning servicesmore-content
Machine learning domain background

Your journey with PixelPlex starts here

STEP 1

Reach out – no pressure

  • Drop us a line, call, or fill out our form. Tell us what's on your mind, no obligation.
STEP 2

Deep dive: consultation

  • Let's discuss your goals, budget, and timeline. We want to fully grasp your vision and needs.
STEP 3

Project plan & estimate

  • Receive a clear roadmap, scope of work, and investment estimate.
STEP 4

Kickoff & development

  • Once aligned, we’ll sign the agreement and launch your project.

FAQ

What's the difference between REST and GraphQL, and which should we use?

REST works well when your data maps cleanly to resources and clients have predictable needs. GraphQL is a strong fit when you have many client types or screens that each need a different slice of data and you want to avoid building an endpoint for every view. We recommend one over the other during discovery based on your specific case, and the two can coexist in the same system.

Can you work with our existing API instead of starting over?

Yes. A large share of our work involves extending, documenting, securing, or modernizing APIs that are already in production. Our solution architecture consulting services include reviewing the current implementation and recommending the change that meets your goal.

How do you handle API security?

We implement authentication (commonly OAuth 2.0 or OpenID Connect), role-based or attribute-based authorization, rate limiting, input validation, and encryption in transit, and we run security testing against the API. For regulated industries, we design around the relevant standards such as PCI DSS or HIPAA.

How long does an API project take?

A focused integration or a small set of endpoints can take a few weeks. A larger platform API with multiple blockchain integrations, custom business logic, and full documentation usually runs two to four months. We give a scoped estimate after discovery.

Will the API be documented?

Yes. Every engagement includes reference documentation, schema definitions (OpenAPI for REST, the schema itself for GraphQL), example requests and responses, and an integration guide.

Can you integrate third-party services like Stripe, Salesforce, or SAP?

Yes. We regularly integrate payment processors, CRMs, ERPs, shipping carriers, data warehouses, and cloud services. We handle the authentication flows, data mapping, webhook handling, and error recovery that each integration requires.

Do you provide ongoing maintenance after launch?

Yes. Our API maintenance and support covers monitoring, dependency updates, versioning, bug fixes, and adding endpoints as your product evolves. If you prefer to keep maintenance in-house, we hand off with documentation and a runbook.

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