Numstack

Expert Powered Consulting

Solve your problems with current experts from your field.

Numstack builds your team from senior specialists shipping in their field right now. You get current, hands-on judgement on your problem: defining the possible solutions, testing which ones work, and building the one that wins.

How current is your expert?In-market
Typical consultantPre-LLM playbooks
Numstack
Fellow
Shipping LLM systems
Kofi A. · Senior AI Engineer · in production
Shipped a RAG assistant2 wks ago
34% LLM inference cost cutthis qtr
Deployed fraud-detection modelthis qtr

Free 45-minute discovery call. No pitch, no obligation.

How we build your team

A team assembled around your problems.

Numstack has no fixed bench. For each engagement we draw from the collective and appoint only the specialists your problem needs, senior people still doing the work in their field today.

It is matched to you, not made to fit. Appoint or pass a few specialists yourself to see how we shape teams.

Assemble your team0 appointed
Amara O.
Senior Product Lead
In-market
NowLeading payments at a top-10 fintech
Product

Tap to appoint or pass. Illustrative of how we build your team.

Our practices

Six connected practices covering the work most businesses need

Each team draws on senior specialists still active in the field, so the thinking reflects how the work is done today, not a generic template.

Strategy & Transformation

Set direction and reshape the business for where it is going.

Operations & Performance

Run better, at lower cost and higher quality.

Commercial & Growth

Win more customers, revenue and markets.

Customer & Experience

Design experiences customers stay for.

Digital, Product & Technology

Build the products, platforms and technology that power it.

Brand, Marketing & Comms

Shape the story and take it to market.

Where we go deep

Deep experience in hard spaces, an open door to new ones

These are the spaces where we've built the most, where the details really matter. The fundamentals of good product travel, so whatever you're building, you get a team that has solved hard problems before.

In-roleConsulting
  • Built and scaled payment rails in production
  • Built and ran fraud prevention and risk mitigation systems
  • Built and managed credit-risk models
In-role
  • Shipped LLM systems and recommendations at scale
  • Set up model evaluation and data pipelines
  • Built credit-risk models using reinforcement learning
In-role
  • Rebuilt funnels that lifted conversion
  • Built intelligent shopping and checkout flows
In-role
  • Built rewards and loyalty flows that improved retention
  • Improved reactivation and lifecycle revenue
  • Built early churn detection for proactive engagement
In-roleConsulting
  • Advised on liquidity, matching, and trust & safety
  • Grew supply and demand in balance
  • Sourced and coordinated partnerships for a unique marketplace
In-role
  • Built pipelines and warehouses teams rely on
  • Made data trustworthy and fast to query
  • Built MCPs so teams query data in natural language
Consulting
  • Ran penetration testing to harden a client's systems
  • Tightened data handling and access controls to reduce exposure
  • Closed security gaps before they could be exploited
Consulting
  • Built a litigation management system that cut undefended cases and default judgements
  • Balanced panel allocation and centralised governance to reduce litigation costs
  • Gave legal teams one place to track and act on every matter
Consulting
  • Delivered environmental compliance and permitting, including water-use and emissions licensing
  • Ran impact assessments and groundwater and air-quality monitoring
  • Planned mine closure and rehabilitation, including financial provision
Consulting
  • Built driver routing and planning with real-time route optimisation
  • Optimised delivery and collection routes for efficiency
  • Tracked inventory across the full courier lifecycle

This is where we've gone deepest so far, not the limit of where we work. Building in a different industry? That's often the most interesting conversation to have.

Have a problem worth solving?

Get senior, in-market judgement on it in a free 45-minute discovery call. No pitch, no obligation, and a straight answer either way.

Book a free consult

Why the collective

The difference is in how the work actually gets done

Not a promise, but tangible differences you feel across the engagement. A traditional consultancy sends advisers a step removed from the work; we build each team from specialists still doing it today.

Typical
Career consultants

Advising from playbooks that have aged out.

Numstack
Specialists still in the game

Still doing the work today, in your sector.

Typical
Partners pitch, juniors deliver

The senior names leave after the sale.

Numstack
Senior people stay hands-on

Who scopes it is who delivers it.

Typical
Siloed by department

One lens on a cross-cutting problem.

Numstack
We work across functions

Strategy, product, growth and brand, joined up.

Typical
A deck and a handover

Advice that looks good but stalls.

Numstack
Implementation-led

We help ship it, not just advise.

Typical
A fixed bench to staff

The team you get is the team they have.

Numstack
Built around your problem

The team is assembled to fit the work.

Typical
Ongoing dependency

Designed for the next engagement.

Numstack
We leave you more capable

Skills transferred, so the gains stay.

The Numstack Collective

Great at what you do?
Join the collective.

We build our teams from a collective of senior specialists. Become a Numstack Fellow, consult on projects that fit you, and earn a second income without leaving your job.

  • Product
  • Engineering
  • Design
  • Data & AI
  • Strategy
  • Marketing
  • Go-to-market
  • Business development

Access without the overhead

The best input, at a fraction of the cost

The best people in product, engineering, and AI already have jobs, and hiring them full-time is slow and expensive, if you can get them at all. The Numstack Collective gives you their current, in-market expertise exactly when your problem needs it, and only for as long as it does. You get senior judgement on tap, without a senior salary on the books.

Senior, not full-time

×A permanent salary on the books
✓Senior operators on your problem

Only what you need

×Paying for an idle bench
✓Only the input the problem calls for

Current, not cached

×Five-year-old playbooks
✓People building in the market today

How we think

Practical techniques, quality product, world-class engineering

Problems first, features second

We start from the real-world problem and the customer feeling it. Everything we build has to earn its place against that.

A senior collective, not a factory

You work with experienced professionals who currently ship and scale real products in your field, not a rotating bench, with theoretical knowledge.

Practical over theoretical

We use lean, proven techniques to move fast and reduce risk, favouring evidence and shipped software over slideware.

Next step
No fluff.
What you get on the call

Let's find out if we can help.

Book a free 45-minute discovery call. We'll dig into the problem you're solving, tell you honestly whether we're a fit, and outline what we could deliver together.