For e-commerce brands from $2M to $20M

Your next stage of growth needs someone that did it before.

I help founders turn unclear numbers, underperforming campaigns and disconnected teams into a growth operation built to scale.

Tell me where growth feels stuck. We will look at the business, team and channels, and determine where I can help.

Brands I have worked with

Recognition

Does this sound familiar?

The company is spending, campaigns are running and people are busy. But growth is becoming harder, more expensive and less predictable.

  1. Growth is stalling.
  2. ROAS drops when budgets scale.
  3. The team lacks paid-channel knowledge.
  4. Budget feels wasted instead of efficiently invested.
  5. There are no clear commercial goals.
  6. There is no clear growth strategy.

Likely causes

The visible problem is not always the real constraint.

My job is to determine which situation exists before prescribing a solution.

01

Diagnostic patterns

ROAS falls every time you scale Meta

Spend works at one level, then efficiency drops as soon as the budget increases. Before blaming the channel, I look at creative volume, campaign structure, conversion and new-customer economics.

02

Diagnostic patterns

Revenue is growing, but cash is not

The dashboards look healthy, but discounting, returning customers and weak margins may be hiding unprofitable acquisition. The targets need to reflect contribution margin and new-customer value.

03

Diagnostic patterns

Everyone is busy, but nobody owns growth

The media agency, email team and developers all report wins, yet the business misses plan. The fix is one commercial target, clear responsibilities and a weekly decision rhythm.

04

Likely causes

Campaigns are not structured for scale

More budget exposes weak campaign architecture, limited creative volume and unclear testing rules. The account needs a structure that can absorb more spend without losing control.

05

Likely causes

The strategy is unclear

Revenue can grow while profit and cash weaken when targets ignore margin, new-customer value and the role of promotions. The business needs one commercial view of growth.

06

Likely causes

The internal team needs leadership

When agencies, paid media, email and developers optimize separately, activity increases but ownership disappears. The team needs one goal, clear responsibilities and a weekly decision rhythm.

Channel expertise

You need to know the channels well enough to challenge the people running them.

I am a Meta specialist with hands-on experience across Google, TikTok, Pinterest, Reddit, Snapchat, Klaviyo, email and CRO. That depth lets me separate a channel problem from weak creative, poor conversion, unreliable measurement, the wrong targets or a team that needs stronger direction.

Meta AdsGoogle AdsTikTokPinterestRedditSnapchatKlaviyo
Email & lifecycleCRO & landing pagesPromotions & offersAttribution & first-party dataSEO & AI visibility

Account evidence

The work is hands-on, not theoretical.

Selected one-month snapshots from Meta and Google accounts I have managed. These are platform-reported results from individual accounts and campaigns, not promises of future performance.

Meta

Selected campaign · One-month account snapshot

Spend
€448,511.47
Purchases
2,029
Cost per purchase
€221.05
Meta. Selected campaign · One-month account snapshot.View full size

Selected campaign · One-month account snapshot

Spend
€27,771.69
Purchases
3,691
Cost per purchase
€7.52
Platform ROAS
13.60
Meta. Selected campaign · One-month account snapshot.View full size

Google Ads

One-month account snapshot

Spend
€53,763.52
Conversions
6,275.20
Conversion value
€593,682.67
Conversion value / cost
11.04
Google Ads. One-month account snapshot.View full size

One-month account snapshot

Spend
€45,667.91
Conversions
6,457.31
Conversion value
€426,986.14
Conversion value / cost
9.35
Google Ads. One-month account snapshot.View full size

Are your campaigns actually ready to scale?

Book a call
Campaign performance screenshot
Miguel Casteleiro discussing strategy in a working session

What I do

I find what is stopping growth and turn it into a plan your team can execute.

I work above day-to-day execution. I establish the numbers and targets that matter, identify the real constraint, decide where budget should go and make clear who owns each next step. If the agency is the problem, I will say so. If the internal team needs coaching, I help lead it. If conversion, retention or measurement is the constraint, we fix that before spending more.

Ways to work together

Choose the level of leadership you need.

Growth is not a collection of channels. It is a management system.

I bring the six parts of growth into one plan so teams stop optimizing isolated metrics and start working toward the same commercial outcome.

The operating model

The six parts I bring into one growth plan.

GrowthLeadership
01

Economics

Know what profitable growth allows you to spend.

02

Measurement

Know which numbers can be trusted.

03

Acquisition

Give every channel a role and clear scaling rules.

04

Conversion

Turn more paid traffic into customers.

05

Retention

Increase repeat purchase and customer value.

06

Execution

Give teams and agencies clear goals and ownership.

A disciplined sequence

How we get growth moving again

  1. Get the numbers straight
  2. Find what is actually stuck
  3. Decide what matters now
  4. Get the right people working on it
  5. Review, learn and scale

Builder credibility

I have also built the systems behind the decisions.

E-commerce attribution and first-party data

Built to close tracking gaps, improve event quality, unify marketing data and help teams make decisions with greater confidence.

Visit MarvelPixel ↗

The leading AI visibility platform built for agencies

Audits, competitor monitoring, citation intelligence, content workflows and reporting for the next era of brand discovery.

Visit SEOforGPT ↗
5companies maximum

Capacity

Direct involvement, by design.

I work with no more than five companies at a time so I can remain directly involved in the decisions, teams, and numbers.

Frequently asked questions

Questions founders usually ask

Direct answers about fit, scope and what working together actually looks like.

01Is this only for e-commerce companies between $2M and $20M?

That is the range where I am usually most useful because the business already has traction, people and meaningful marketing spend, but growth has become harder to direct. I have worked with companies from $1.5M to more than $250M, so larger businesses can still be a fit.

02Are B2B businesses also eligible?

Yes. I have worked extensively with B2B companies across industries including IT providers, B2B applications, platforms, furniture, real estate and government services. The same work can be valuable when the business has a meaningful acquisition operation, an existing team or agencies and needs clearer commercial targets, channel strategy and accountability.

03What will I actually get from the 3-Month Growth Advisory?

The advisory is built around a weekly or biweekly working session with you and the people responsible for growth. Together, we review financial planning, attribution, current performance and every active channel. We inspect and revise campaigns where needed, coach media buyers on how to optimize and scale, and build the decision-making skills your team needs to run growth more effectively after the engagement ends.

04How is Fractional Head of Growth different from advisory?

With advisory, I work alongside your existing growth leader to improve the quality of the work, channel management and decisions being made. As Fractional Head of Growth, I actively direct agencies and specialists, lead the weekly growth rhythm and take responsibility for keeping the complete plan accountable.

05Will you replace my current agency or media buyer?

No. I first establish the current state of the business and determine whether what is missing is strategy, agency capability, internal leadership, reliable measurement, conversion, retention or something else. If the agency is capable, I give it clearer targets and direction. If the agency is the constraint, I explain exactly why.

06What happens on the discovery call?

We discuss your current revenue, targets, team, agencies, channels and where growth feels stuck. The goal is to understand the situation and decide whether advisory, fractional leadership or neither is the right next step. It is not a disguised sales presentation or a separate paid product.

Find out what is really holding growth back.

Tell me where growth feels stuck. We will look at the business, team and channels, and determine where I can help.

Book a discovery call