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E-commerce agency

E-commerce agency for SMEs: custom stores and buying journeys

PeakLab designs, rebuilds and connects B2B and B2C e-commerce sites when your catalog, pricing or operations exceed a standard theme. The choice between CMS, headless and custom starts with your sales, workflows and team.

Verifiable commitments for your e-commerce platform

Written scope and ownership

Catalog, journeys, integrations, data, roles and acceptance criteria are approved before development.

Budget and schedule by workstream

The proposal separates scoping, design, commerce engine, connectors, migration, testing, launch and operations.

An autonomous team

Access, catalog, order, promotion, incident and routine change procedures are documented and handed over.

Reversible launch and monitoring

Cutover, recovery, monitoring and support ownership are defined according to the project's risks.

CMS, headless or custom e-commerce: what should you actually build?

The French government guide published on December 5, 2025 distinguishes three paths: a managed CMS, fully custom development or a turnkey SaaS product. A standard store is often better served by Shopify, WooCommerce or PrestaShop: a conventional catalog, common payment journey and small team do not automatically justify a bespoke platform.

Headless or custom becomes relevant when the buying journey creates a real advantage: a configurator, B2B pricing rules, complex catalogs, recurring orders or deep ERP, CRM, PIM, WMS and carrier integrations. We compare initial cost, recurring fees, dependencies, operations and reversibility before recommending an architecture. Our CMS versus custom guide explains this decision.

  • Sales model: B2C, B2B, subscription, quote, marketplace or hybrid journey
  • Catalog: variants, pricing, stock, content, availability rules and data quality
  • Operations: orders, invoices, returns, customer service, logistics and reconciliation
  • Decision: CMS, headless and custom compared with assumptions and operating costs

Why choose an e-commerce agency that may recommend a standard CMS?

Because your margins and operations matter more than a technology preference. PeakLab combines product, UX, web development, SEO and business integrations: we can keep a CMS, build a headless storefront or develop only the logic that differentiates you. You receive a reasoned recommendation, cost assumptions and operating limits before funding the solution.

What our e-commerce agency delivers

Six deliverables connecting the buying experience to the catalog, payments and real operations of your SME.

01

Sales model audit and architecture decision

We map customers, channels, catalog, volumes, margins, promotions, orders, returns and existing tools. The deliverable compares configuring a CMS, extensions, headless and custom development, including cost assumptions, dependencies and operational workload. Custom is selected only when its value offsets its complexity.

02

Testable product, cart and checkout journeys

Search, categories, product pages, variants, availability, cart, account and checkout are prototyped on mobile and desktop. Acceptance covers the happy path, errors, stockouts, price changes, delivery, returns and accessibility. Decisions use a baseline and measurable events without promising a universal conversion rate.

03

Commerce engine, catalog and business rules

We configure or build products, variants, bundles, pricing, B2B accounts, quotes, promotions, stock and orders as required. Systems of record and administration rights are explicit. Imports, bulk updates, conflicts and histories are tested so the team can operate the back office.

04

Payments, fraud, taxes and journey compliance

The payment provider and methods depend on countries, amounts, risks and customer habits. We favor hosted or tokenized components to reduce exposure to card data, then test authentication, declines, refunds, double submissions and recovery. Legal notices, terms, consent and sector rules are validated with your qualified advisers; PeakLab does not provide legal advice.

05

ERP, CRM, PIM, logistics and invoicing

Every connector defines the data owner, frequency, idempotency, errors, recovery and monitoring. Stock, customers, orders, shipments, returns and invoices are not assumed to synchronize without incidents. For French B2B flows, we anticipate mandatory receipt of electronic invoices on September 1, 2026 and SME issuance on September 1, 2027, subject to the applicable legal scope.

06

E-commerce SEO, performance, analytics and operations

We deliver stable URLs, redirects, sitemaps, canonicals, controlled faceting and Product/Offer structured data synchronized with visible prices and availability. Google's documentation updated in July 2026 guides merchant markup. Performance budgets, consent-aware analytics, alerts, backups, dependencies and a maintenance plan complete production launch.

Celeste
Excellent DEV. Complex Back and Front mission. The team managed the complexity of a multi-service project with rigor and efficiency.
Fabrice Ducarme
Fabrice Ducarme
Project Manager at Celeste
Read the full case →

From the current journey to an operable store

1

Diagnose

Sales, data and operations

Measure the current journey and qualify catalog, orders, returns, tools, ownership and priority pain points

2

Decide

CMS, headless or custom

Compare options on value, recurring costs, integrations, reversibility, security and operational workload

3

Prototype

Journeys and difficult cases

Test search, product, cart, payment, errors, accessibility and administration on mobile and desktop

4

Migrate

Data and controlled cutover

Rehearse imports and connectors, verify redirects and events, prepare recovery and launch against a shared checklist

5

Operate

Measurement and improvement

Monitor orders, errors, performance, SEO, costs and incidents, then prioritize changes from observed data

Celeste: unifying a B2B offering and its operations

For Celeste, PeakLab worked on a B2B e-commerce platform bringing together several group services, a configuration tool with pricing and a back office connected to order processing. The published testimonial describes a complex project spanning front and back end.

We retain this functional evidence and delivered scope. The previous conversion and average order metrics are not repeated here because their period, attribution and protocol are not documented publicly. Every new project starts from its own data: conversion by step, order errors, catalog quality, operational lead times and support requests.

The scope also includes accessibility, mandatory information and personal data. The French government updated its guides on creating an online store and mandatory website information in December 2025. Online shops are also among the services covered by EU accessibility rules, with exemptions and implementation details to qualify for each business and service.

1 measured journey
step-by-step baseline before the rebuild
Rehearsed cutover
imports, redirects and recovery tested
Autonomous team
access, procedures and ownership handed over

Resources for choosing and evolving your e-commerce platform

Compare CMS, headless and custom, then prepare SEO, catalog and operations before starting a rebuild.

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Should your store be configured, rebuilt or developed as a custom platform?

Let's review your catalog, journeys, tools, constraints and current indicators. You leave with the next decision to make before funding an architecture.

Questions before choosing an e-commerce agency

Architecture, budget, migration, payments, SEO, accessibility and maintenance: decisions to make before a rebuild.

Your project deserves foundations that measure up.

In one call, we tell you what's feasible, at what price, and in what timeframe. With full transparency.

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