Systems studio · Notion · Airtable · Make

Operations that run themselves.

Right now your business lives in your head. I turn it into a system that runs without you: requests, handoffs, approvals and reports move on their own. I've built them for teams from a $15B fintech to luxury villas in Ibiza.

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$15BLargest client

60+Person agency scaled on my systems

80+Notion workspaces built

300+Automation scenarios shipped

Systems running at

Sound familiar?

Every team I work with started here.

These are word-for-word quotes from discovery calls with owners and operators. Different industries, same problem: the work lives in chats, spreadsheets and one person's memory.

"It's just, like, a cluster of chaos."

Operations lead · US events agency

"The CEO is having to check in every day and be like, where's this? Where's that?"

Same agency, before the build

"Every day has its own Word document for all our orders."

Owner · specialty coffee wholesaler

"Most of them were agreed upon three months ago in a group chat that now has another thousand messages after it."

Founder · event gear company

"I have to put the price here, I have to put the price here, I have to put the price here."

Founder · e-commerce reseller

"I'm losing business because this automation is not efficient."

Founder · housing placement network

What I actually build

Not “a Notion setup.” Work that's always in somebody's hands.

Anyone can make databases. Almost nobody architects the system. Every build runs on the same five rules, which I call the Handoff Engine™.

One front door

Every request comes in through one form or one channel, never a DM or a sticky note.

Every step has an owner

Each stage is assigned to a person automatically, with a due date that respects weekends and cut-off times.

"Done" hands it on

Marking a step done creates the next one and puts it on the next person's list, along with the brief and files.

Nothing stalls silently

Anything untouched for too long pings the person responsible before a client notices.

Everyone sees only their list

One "My Tasks" page per person. Clients, freelancers and staff see exactly what they should, and no more.

Selected work

Built for teams that can't afford chaos.

Fintech, Amazon advertising, luxury travel, video production, wholesale. Here's what I built for each, and what changed.

$15B fintech.
One partnerships desk.

Trade Republic · Berlin · valued at €12.5B (≈ $15B)

Europe's fast-growing neobroker was running its partnerships out of Excel and inboxes. I built a Notion partnerships directory and deal tracker: every firm, deal, contact and touchpoint linked, with separate partnership and procurement views and one-click activity logging. It's set up so the whole department works in it, mostly as free guests rather than paid seats.

4 linked databases: firms, deals, contacts, activity log
16+ purpose-built views for partnerships and procurement
One-click logging, so the log actually stays current
Ordered mid-call, approved and delivered

Sellers Side

UK · Amazon PPC

A data platform for 50+ Amazon brands

Sellers Side runs Amazon advertising for e-commerce brands. I built their multi-tenant analytics platform: nightly pipelines from the Amazon Ads and Selling Partner APIs into BigQuery, live dashboards, shareable reports and a self-serve seller onboarding flow. It covers ~340 advertiser profiles across the US, UK and EU.

Amazon Ads APIBigQueryCloud RunMulti-tenant

Ibiza · Luxury villas

80 villas, up to €40k a week, one hub

Maven Collection has run its booking system (iPro) for a decade. I synced it into a Notion operations hub for villas, owners, bookings and clients. A locked-down financials layer keeps commission private from staff, each villa has its own 40-question owner onboarding form, and branded guest emails cover every step from booking to arrival. Emma chose it over her booking software's own CRM.

iPro APINotionMakeGuest emails

Turnovers that dispatch themselves

A South Carolina rental manager with 11 homes on Guesty. New bookings create the clean and post it to that home's Slack channel. AI reads the cleaner's "accepted" reply, and the system sends day-before reminders, nags when nobody accepts and handles cancellations. I also rebuilt their website, staysc.com.

GuestySlackAI

Haarlem, NL

A video agency's production line

About 17 live projects across three editors and a bench of freelancers, all in one pipeline: clients, campaigns, videos and stage tasks. "Done" creates and assigns the next task. Client portals show progress, and freelancer pages show what each editor is owed, privately.

NotionMakeGoogle Calendar

US · Brand activations

160 tasks, zero "where is this?"

A 10-person agency where 95% of projects follow the same five phases, yet the CEO checked in on everything daily. Now a 75-step workflow of about 160 template tasks runs on "Done & Next" buttons, yes/no branches, QA kick-backs and automatic producer assignment.

NotionWorkflow engine

The Roadmap Coach

Sell a package, get a project

A business consultancy that moved from Airtable to Notion. Closing a deal in the CRM now spins up the full delivery project automatically: up to 33 tasks, each assigned and given a business-day due date.

NotionAutomations

US nonprofit

A system the team extends itself

A funding-pipeline CRM and donor call system. After a few Loom walkthroughs, the director built a new recurring donor-call plan on her own, which she'd never managed to do in Airtable.

NotionAirtable

Liquid Theory

Brand OS

A brand's whole operating system

Eight areas, from brand and audience to go-to-market and revenue, with tasks, projects, meetings and decisions, and KPIs. It was handed over as a template the team now runs and extends themselves.

NotionTeam OS

Massachusetts · Wholesale

From a Word doc per day to one-click invoices

Wholesale orders used to live in a Word document per day and then get retyped into QuickBooks. Now orders live in Airtable, customers and products sync from QuickBooks every night, a year of invoice history is imported, and each order becomes a QuickBooks invoice with one button.

AirtableQuickBooks OnlineMake

More systems

Clients under NDA

Family office, Canada: AI turns 25–30 daily emails into tasks, files every attachment and syncs three calendars
Healthcare acquirer: an onboarding portal for each acquired company, with progress bars and Slack alerts
Housing placement network: four intake forms flow into Airtable with instant branded confirmations
Events & hospitality group: a six-department workspace with goals, projects and action items
Dutch real-estate group: moved off Monday.com, with automated campaigns and client portals

In their words

What clients said on the calls.

"It's like night and day, Danny. As I'm looking through what you're building, I can see myself using it already. I never got that moment with Airtable."

Christina Bryan · Founder, The Roadmap Coach

"The difference between you and everybody else that I have met with… you are very personable. You understand the overall concept of how to do business with people."

Naomi Raggi · Director of Business Operations, The Roadmap Coach

"You're a specialist in what we need."

Emma Thomson · Maven Collection

"Now I can be on the phone talking to people and doing the relationship thing. And not this stuff."

Founder · housing placement network

"All the tasks just get in there automatically, all those documents get in there automatically, all those meetings get in there automatically. I'm so happy already."

Executive assistant · family office

"That's a massive transformation for us."

Shane · events & hospitality group

How it works

From whiteboard to working in four steps.

01 · MAP

Trace the work

A 90-minute session tracing how one job really moves today: who starts it, who touches it, where it gets stuck.

02 · SKELETON

Sign off the design

I design the structure and you approve it before any building starts. The skeleton is the hard part to change later, so we get it right first.

03 · BUILD

Fast, fixed scope

Most systems are live in days to two weeks, not months. Halfway through, you get a recorded walkthrough and a chance to steer.

04 · LAUNCH

Your team adopts it

A team launch call, a Loom for every role, then adjustments until your team works from it daily.

About

Hi, I'm Danny.

I'm Danail Rusev, founder of BrainBuild, a registered systems studio in Sofia, Bulgaria. I joined an agency when it was the owner, me and two assistants, and built the systems it ran on as it grew past 60 people.

Since then I've built 80+ Notion workspaces and 300+ automation scenarios for agencies, property managers, wholesalers, fintechs and nonprofits. I'm still a member of about 20 of those workspaces today. Clients just never remove me.

I don't start with what you want built. I start with how your work actually moves. Then everything is built in your own accounts with a Loom for every role, so it keeps running even if you never speak to me again.

NotionAirtableMakeSlackQuickBooksGuestySupabaseAI agents

FAQ

Good questions.

Will my team actually use it?

That's what the design is for. Each person opens one page, My Tasks, and sees only their own work. Then there's a Loom for every role, a launch call, and adjustments until it's part of the daily routine.

What if you disappear?

Nothing is locked to me. It all runs in your own Notion, Airtable and Make accounts, every automation is named and documented, and there's a recorded walkthrough for every part. As I told one client: even if you kick me out, it keeps working.

How does pricing work?

Every project gets one fixed price, agreed in writing before kickoff and based on the scope we map on the call. No hourly billing and no surprise invoices.

Can't I just buy a template or have AI build it?

Many of my clients tried that first. Templates are built to look good for everybody, and AI builds a demo. Neither decides who gets the next task, what happens on the third revision, or who's overloaded. That architecture is the part I build.

We already use ClickUp, Monday or spreadsheets. Is that a problem?

No. Migrating your existing projects and records is part of the build.

Where are you based?

Sofia, Bulgaria (EET). My working hours cover all of Europe and US mornings, and calls can be booked in your time zone.

Book a call

An hour, not fifteen minutes.

Most intro calls are 15 minutes. Mine is an hour, because that's how long it takes to trace how work really moves through your business. You leave with a map, even if we never work together.

A map of where your work stalls today
A rough cost of that chaos
A fixed scope and timeline, if it's a fit