Amazon SP-API Integration Agency

Why eSellerBridge

Custom Amazon SP-API integration —
built by specialists, owned by you

Amazon's Selling Partner API (SP-API) is the modern replacement for MWS — and it's complicated. OAuth 2.0 with Login with Amazon, restricted data tokens, regional endpoints, dynamic rate limiting, and a sprawling surface of 100+ endpoints across orders, inventory, listings, reports, feeds, FBA, advertising, and Brand Analytics. Most off-the-shelf SaaS tools cover only the headline endpoints. We build Amazon SP-API integrations end-to-end: every endpoint, every region, every workflow your business actually needs.

eSellerBridge is a specialist Amazon SP-API integration agency. Every engineer on our team works exclusively in marketplace API integration — Amazon Selling Partner API, Vendor Central, Marketing Stream, AMC, and the 50+ other platforms (Flipkart, Walmart, Shopee, Shopify, Google Ads, Klaviyo, Snowflake) that serious eCommerce operations run on.

When to hire an Amazon SP-API specialist

SaaS works for vanilla cases. ChannelAdvisor, Sellercloud, Helium 10 — they're priced for the average seller's average needs. The moment you have a unique workflow (custom repricer rules, AMC audience activation, Vendor Central EDI hybrid with Seller Central data, multi-account ops), you hit the wall. Most 7-figure brands stitch together 8-12 SaaS tools that bleed $2,000+/month and still leave gaps.

DIY works if you have an in-house team. But Amazon's APIs change quarterly. Marketing Stream consumers replaced batch reports in 2023. AMC clean-room SQL rules tightened in 2024. Vendor Central EDI requirements vary by category. Keeping up is a full-time job.

Specialists work if you want it built right and owned forever. We deliver custom-built software that you own outright — no per-seat pricing, no usage caps, no vendor lock-in. Hosted in your cloud, in your repo, with full documentation. Most clients see ROI inside 6 months from SaaS replacement alone.

Our Amazon-first integration capabilities

Amazon SP-API: Full OAuth 2.0 / LWA setup, all 100+ endpoints across Orders, Listings, Reports, Feeds, FBA Inventory, and Catalog Items. Multi-region support across all 24 Amazon marketplaces.
Amazon Marketing Stream: Hourly Sponsored Ads data via SQS or Kinesis Firehose. Replaces 24-hour batch reports with sub-2-hour latency.
Amazon Marketing Cloud (AMC): Clean-room SQL across Amazon Ads + DSP signals. Custom audience activation, lookalike modeling, true incrementality testing.
Amazon Vendor Central: EDI 850/856/810 automation, ARA Premium extraction, chargeback recovery, shortage claim filing, Vendor Powered Coupons.
Amazon Multi-Channel Fulfillment (MCF): Use FBA inventory to fulfill Shopify, BigCommerce, eBay, and DTC orders. Branded packaging, shipping speed routing, tracking sync.
MWS to SP-API migration: Zero-downtime parallel-run migrations from the legacy MWS API, with full endpoint mapping and credential rotation.

Beyond Amazon: 50+ marketplace, ad, and data integrations

We integrate Amazon alongside everything else your operation runs on. Marketplaces: Flipkart, Walmart, Shopee, eBay, Meesho, TikTok Shop, Lazada. Storefronts: Shopify, WooCommerce, Magento, BigCommerce. Advertising: Google Ads, Meta Ads, TikTok Ads, Walmart Connect. Email & analytics: Klaviyo, Mailchimp, GA4. Data warehouses: Snowflake, BigQuery, Redshift, Databricks. Operations: ShipStation, NetSuite, QuickBooks.

Engagement models

Choose the model that fits — hire Amazon SP-API developers on a dedicated, project, or retainer basis. You can also engage the full team for fixed-scope builds with milestone-based payments.

Stop renting $2,000+/month
of SaaS subscriptions

Most 7-figure Amazon brands stitch together 8–12 SaaS tools that bleed cash monthly — and still leave gaps. We replace the stack with custom software you own outright.

Typical SaaS stack

$2,056/ month

$24,672 / year — and growing

✕Inventory & repricing$399
✕Sponsored Ads automation$497
✕Brand Analytics dashboard$249
✕Reimbursement & FBA recovery30% of recovered
✕Helpdesk & review monitoring$199
✕Listing optimization tool$179
✕Cross-channel order routing$299
✕BI reporting layer$234

Per-seat pricing • Usage caps • Vendor lock-in • Data leaves your control

Custom build · own forever

eSellerBridge custom build

$0/ month

One-time build · zero recurring SaaS fees

✓All of the above — built into one system
✓No per-seat pricing — unlimited team members
✓No usage caps — your data, your rules
✓Tailored to your exact workflows
✓You own the code, repo, and infrastructure
✓Add features whenever you need them
✓Hosted in your cloud (AWS / GCP / Azure)
✓ROI typically inside 6 months

Calculate your savings →

Built for businesses
that sell everywhere

Amazon Sellers & Vendors

Scale your Amazon operation with custom SP-API tools, automated reporting, inventory intelligence, and seamless third-party integrations.

✓SP-API custom app development
✓Seller Central automation
✓Multi-account management tools
✓FBA/FBM hybrid operations

3PLs & Fulfilment Providers

Offer your clients seamless marketplace connectivity. We build the integration layer that makes your 3PL a competitive advantage.

✓Multi-marketplace order ingestion
✓WMS integration & automation
✓Real-time inventory sync
✓Client portal development

SaaS Companies & Agencies

Add marketplace API functionality to your existing product without hiring an in-house team. We integrate, maintain, and scale.

✓Marketplace API as a service
✓White-label integration builds
✓Ongoing maintenance & support
✓Amazon App Store listing support

From brief to live integration

Discovery Call

30-minute session to understand your systems, goals, and integration requirements. No sales pressure.

Technical Scoping

We map your data flows, define API endpoints, and deliver a detailed technical specification and timeline.

Build & Test

Agile development with weekly demos. Full test coverage before any code goes near your production environment.

Deploy & Support

Live deployment with monitoring, documentation, and ongoing support. We don't disappear after launch.

Specialists,
not generalists

Every engineer at eSellerBridge works exclusively in marketplace API and eCommerce integration. You get depth, not bandwidth.

⚡

Amazon SP-API Certified

Our team has built and maintained SP-API integrations across all 24 Amazon marketplaces — from Listings to Brand Analytics to Advertising API.

🌏

Truly Global Coverage

We don't just do Amazon. We speak Flipkart's Marketplace API, Shopee's Open Platform, Walmart's Seller API, and every regional marketplace that matters.

🔧

Custom-Built, Not Off-the-Shelf

Every integration is built to your exact specifications. No compromises from a one-size-fits-all product. Your workflows, your data model.

🛡️

No Revenue Share. No Commission.

Fixed-scope projects and transparent retainers. We earn from building excellent software — not from taking a cut of your revenue.

What our clients say

★★★★★

“eSellerBridge built our entire SP-API integration layer from scratch — orders, inventory, and advertising in one system. They understood Amazon's API quirks better than anyone we'd worked with before.”

Rahul K.

CTO, 8-figure Amazon Brand · India

★★★★★

“We needed a single system connecting our Amazon US, Walmart, and Shopify stores to our 3PL. The eSellerBridge team scoped it perfectly, built it fast, and the integration has been rock solid for 6 months.”

Marcus W.

Operations Director · US eCommerce Brand

★★★★★

“We added Flipkart and Meesho integration to our SaaS platform using eSellerBridge. The API complexity was handled completely on their side. Our devs just consumed the clean unified output.”

Ananya P.

Founder, eCommerce SaaS · Bengaluru

Frequently asked
questions

Simple connectors (orders + inventory) start at $8k–$15k. Full multi-marketplace builds with Marketing Stream, AMC, and warehouse loading run $30k–$80k. We scope every project on a free 30-min discovery call and quote a fixed price.

Simple integrations ship in 3–5 weeks. Full multi-marketplace builds with Advertising and Brand Analytics typically take 8–12 weeks. We deliver in 2-week sprints with weekly demos.

Yes — MWS migrations are one of our most common projects. We run both APIs in parallel during the transition window, so there's zero downtime and zero data loss.

Yes. Our team holds Amazon SP-API Developer credentials and we've shipped integrations across all 24 Amazon marketplaces. We also build and ship apps to the Amazon Selling Partner App Store.

Yes. We offer monthly maintenance retainers covering API updates, new endpoints, and incident response — Amazon's APIs change quarterly and most clients keep us on retainer.

Yes — through our Hire Talent program. Dedicated developers, project basis, or retainer bench. You interview the candidate, we handle contracting, payroll, and time-zone overlap.

Yes. Custom code we build for your project becomes your property — full ownership of the repo, the data, and the roadmap. No revenue share, no licensing, no lock-in.

Custom Amazon SP-API
& Marketplace
Integration

Custom Amazon SP-API integration —
built by specialists, owned by you

When to hire an Amazon SP-API specialist

Our Amazon-first integration capabilities

Beyond Amazon: 50+ marketplace, ad, and data integrations

Engagement models

Stop renting $2,000+/month
of SaaS subscriptions

End-to-end API integration
& development services