Marketplace Growth Manager | E-commerce & Sales Development

I grow salesI increase profitabilityI automate processes

I build and grow marketplace sales — from channel launch and advertising to analytics, optimization and automation.

3+ yearsin e-commerce
10+ channelsmarketplace & e-commerce
2000+ SKUunder management
Europeinternational markets

WHAT I BRING TO THE BUSINESS

I grow sales. I improve performance. I automate

SALES GROWTH

I launch and grow sales channels

I launch products on new marketplaces and develop existing accounts across catalog, content, SEO, advertising, pricing and promotions.

Launch → Optimize → Grow
PERFORMANCE

I find growth opportunities in data

I analyze sales, advertising, assortment and competitors to identify what should be scaled, optimized or discontinued.

Analyze → Decide → Improve
AUTOMATION

I reduce manual work

I automate reporting, advertising monitoring, catalog operations and recurring workflows using APIs, Python and AI.

Less manual work → More control → Faster scaling

HOW I WORK

From analysis to results

Analysis

I analyze sales, competition, costs and market potential to identify problems and growth opportunities.

Strategy

I define goals, priorities and an action plan based on sales potential and profitability.

Execution

I implement solutions and optimize offers, advertising campaigns and operational processes.

Optimization

I monitor KPIs, review results and expand the activities that deliver the strongest outcomes.

PROFITABILITY

Marketplace profitability and financial analysis

I analyze product, packaging, logistics, marketplace commission and advertising costs. I compare sales-channel economics and identify opportunities to improve profitability.

Cost analysis · Channel profitability · Pricing strategy · ROAS / ACOS / TACOS

BUSINESS DECISIONS

Not every increase in sales means higher profit

Before launching a channel, I assess its potential, costs and likely profitability. I compare marketplace performance and recommend solutions with a sound business rationale.

SELECTED PROJECTS

Results I've Delivered

Amazon.de

Growing sales on Amazon.de

Amazon Ads · Offers · Customer feedback · Sales analytics

4.6 → 8ROAS5% → 1%return rateTOP 2category position€15K+monthly revenue
Challenge

Improve sales efficiency and reduce the high return rate.

Actions

Analyzed PPC campaigns, optimized offers and identified return drivers using customer feedback and sales data.

Result

ROAS increased from 4.6 to 8, the return rate fell from 5% to 1%, the product reached TOP 2 in its category, and monthly revenue exceeded €15,000.

Allegro

Managing and growing Allegro sales

2000+ SKU · Allegro Ads · Analytics · API · Automation

−30%advertising spend7.9 ROASmaintained2000+ SKUunder management
Challenge

Improve advertising control across several Allegro accounts.

Actions

Audited campaigns, restructured offers, optimized CPC and budgets, and automated reports and alerts.

Result

Advertising spend fell by about 30% while ROAS remained at 7.9.

Leroy Merlin

Launching and growing Leroy Merlin

Launch from zero · Mirakl · Catalog · Retail Media

270K+ PLNfirst five months of 2026
Challenge

Launch and develop a new sales channel from scratch.

Actions

Assessed platform potential, prepared the product catalog, and optimized offers, pricing and promotional activity.

Result

Revenue exceeded PLN 270,000 in the first five months of 2026.

Castorama

Launching sales on Castorama

Channel launch · Catalog integration · Pricing · Availability

66K PLNfirst five months of 2026
Challenge

Launch another sales channel and adapt the offer to the platform’s requirements.

Actions

Prepared offers, integrated the catalog, and managed pricing and product availability.

Result

Revenue reached PLN 66,000 in the first five months of 2026.

PLATFORMS

Platforms I've Worked With

Experience across marketplace management, catalogs, advertising, integrations and product visibility.

AmazonMarketplace
AllegroMarketplace
Leroy MerlinMarketplace
CastoramaMarketplace
EmpikMarketplace
Media ExpertMarketplace
MoreleMarketplace
CeneoMarketplace
TikTok ShopMarketplace
Facebook MarketplaceMarketplace
Google Merchant CenterProduct & advertising channel

How I develop a marketplace

Analysis

Sales potential · competition · pricing · assortment

Launch

Integration · account setup · marketplace requirements

Catalog

Offers · SEO · content · attributes

Growth

Advertising · promotions · visibility

Analytics

Sales · ROAS · profitability · competitors

Optimization

Budget · prices · offers · processes

Scale

Automation · assortment · new opportunities

AmazonAllegroMiraklSellasistBaseLinkerHelium 10AmazonAllegroMiraklSellasistBaseLinkerHelium 10
PythonREST APIPlaywrightGoogle AdsGA4GTMMerchant CenterAIPythonREST APIPlaywrightGoogle AdsGA4GTMMerchant CenterAI
MARKETPLACES

Amazon · Allegro · Mirakl · Leroy Merlin · Castorama · Empik · Media Expert · Morele · Ceneo · TikTok Shop

MANAGEMENT / INTEGRATION

Sellasist · BaseLinker · PrestaShop · WooCommerce

ANALYTICS / MARKETING

Google Ads · Helium 10 · Sellerboard · GA4 · GTM · Google Merchant Center

AUTOMATION / TECH

Python · REST API · Playwright · AI

APPROACH

I treat a marketplace as a business, not a collection of separate tasks

Sales, advertising, assortment, pricing, analytics and operations are interconnected. I start with the business goal and data, implement the right change, then automate what can be scaled.

MARKETPLACE BUSINESS
SalesMarginAdvertisingAssortmentPricingOperationsAnalytics

AUTOMATION

Marketplace process automation

Automating promotional price updates reduced the process from around two hours to five minutes.

Python · REST API · Playwright · AI
2 hours → 5 minutes

ABOUT

E-commerce is more than marketplace administration

I work with e-commerce and marketplaces end to end: from launch and daily channel management to advertising, analytics and automation.

I look beyond how a platform works to understand its impact on sales, margin and the wider business. That is why I combine commercial work, performance marketing, data and technology in one system.

I can launch a channel, find growth opportunities and build processes that remain manageable as the business scales.

CONTACT

Let’s talk

Have a project, opportunity or challenge worth discussing? Send me a message and I’ll get back to you.

Download CV ↓

Warsaw, Poland

AmazonAllegroLeroy MerlinCastoramaEmpikCeneoMedia ExpertMoreleTikTok ShopFacebook MarketplaceGoogle Merchant CenterAmazonAllegroLeroy MerlinCastoramaEmpikCeneoMedia ExpertMoreleTikTok ShopFacebook MarketplaceGoogle Merchant Center