Sales & MarTech systems · Lisbon, Portugal

Less busywork.
More business.

I build connected systems for sales, marketing, and operations, from prospect data and CRM workflows to automation and AI.

I'm Oscar Tellez. I combine hands-on development with sales and marketing experience to build automations, integrations, AI tools, and full-stack apps for go-to-market (GTM) teams.

Discuss a project Explore my work

Hiring? Download my CV

40,000+European e-commerce sites covered
by sales intelligence workflows

Business context. Technical execution.

Oscar Tellez, MarTech developer based in Lisbon

Oscar TellezAI, automation & data

Python · JavaScript · Google Cloud

Experience spanning
development & commercial teams

Googlevia Algomarketing

Growth HorizonMarketing automation

PriceShapeSales & analytics

01 / Flagship projects

Real problems.
Working solutions.

Data pipelines, integrations, full-stack applications, and AI agents, built around the way sales, marketing, and operations teams work.

01Featured / Marketing measurement

growth-metrics.

Your marketing performance. Your measurement gaps. One clearer picture.

Order revenue and platform reports only tell part of the story on their own. growth-metrics brings Google Ads attribution, Meta revenue, and Klaviyo reporting alongside order revenue in one workspace.

Channel views, conversion signals, and data-quality checks help compare performance and reveal missing data before drawing conclusions.

What it enables

Explore performance across channels while seeing where missing data limits the picture.

Google Ads
Meta
Klaviyo
Data quality

Ask me about this project

Redacted growth-metrics interface showing order revenue, Google Ads, Meta, channel reporting, and data-quality views — App view with client details and commercial figures redacted. View larger

Redacted Revenue Desk dashboard with navigation for invoicing and the Ozzie conversational assistant — Revenue Desk + Ozzie · redacted app view

02Revenue Desk + Ozzie / Agency operations

One workspace.
Fewer operational handoffs.

I built Revenue Desk to connect agency onboarding, Klaviyo data ingestion, revenue tracking, and client-specific pricing. Integrations with Klaviyo, Gmail, and Adversus bring marketing performance and sales activity into the same workspace.

Revenue and pricing feed performance-based billing, PDF invoices, email templates, and Gmail drafts, linking reporting to invoicing and agency profitability.

Ozzie connects to operational and financial databases, error logs, and executable tools. It answers business questions, helps troubleshoot issues, and generates invoices through natural-language commands.

The value: connect the work from onboarding through to billing.

Web application
API integrations
Workflow automation

Ask me about Revenue Desk

FROM CONVERSATIONS TO CONTEXT

Sales callsTranscriptsAI agent

03Applied AI / Knowledge retrieval

Your sales calls.
Searchable through an agent.

Sales-call recordings are difficult to revisit when the useful detail is buried in audio. I coded this system locally and deployed it on a separate remote PC.

It fetches softphone recordings, transcribes them locally with open-source Whisper, separates speakers, and generates summaries. I connected a Hermes agent to the transcription database so sales teams can ask natural-language questions about calls through Telegram.

The value: help sales teams revisit conversations and retrieve context for follow-up.

Transcription
Hermes agent
Database integration

Ask me about this workflow

04API engineering / Growth Horizon

Integrations where native connectors fell short.

When native connectors did not cover the required workflows, I built custom integrations between Klaviyo and Lightspeed, Mijnwebwinkel, and Logic4.

Historical synchronization brings customer history into Klaviyo. Ongoing event-driven synchronization and client-side tracking keep new activity flowing into email marketing workflows, connecting the initial data load with what customers do next.

Python
REST APIs
Google Cloud
JavaScript

Have an integration challenge?

05Data engineering / Sales & GTM intelligence

40,000+ sites.
Structured for sales.

I built scraping and enrichment workflows covering 40,000+ European e-commerce sites. Using Python and Node.js, I cleaned, enriched, and structured the scraped data for targeted outbound.

Prepared prospect data supports lead qualification and sales prioritization.

Python
Node.js
Data enrichment

Let's talk about your data

Much of my work lives inside private business systems. Happy to discuss the architecture, decisions, and implementation in a conversation.

02 / How I help

Where is your team
losing time?

Connect the work from finding the right prospects to following up, measuring results, and onboarding customers.

“Our tools don't talk to each other.”

Connect your stack.

Custom API integrations and data pipelines that keep your CRM, softphone, marketing platforms, and business systems in sync.

Python · REST APIs · Google Cloud

“Our sales team is buried in admin.”

Automate sales operations.

From prospect enrichment and CRM workflows to onboarding and invoicing, I automate the manual work around your sales process.

Apps Script · JavaScript · n8n

“We have data. We need answers.”

Make information useful.

Dashboards and AI agents for outreach performance, sales-call knowledge, and marketing results, so teams can ask questions, find answers, and act on their data.

SQL · BigQuery · Looker Studio · AI

Tell me what's slowing you down

03 / The person behind the systems

I understand the work
behind the workflow.

Before building tools for teams, I worked in sales, paid media, procurement, and business operations. That context changes how I build.

I've booked appointments across European markets and used outreach data to improve follow-up. That experience shapes how I build: usable prospect data, connected sales tools, and workflows that support the next conversation.

I've also co-owned a hospitality business, handling bookkeeping, budgets, payroll, and front-of-house operations. That experience keeps the everyday work of running a business in view.

Today, my work through Algomarketing supports Google's event operations in Lisbon, combining Apps Script workflows, data pipelines, lightweight web applications, and AI automation.

Download my CV LinkedIn

Native Spanish · Fluent English · Learning Portuguese

May 2026 — Present Current

Google via Algomarketing

Developer & Delegate Activation Manager

Through Algomarketing, I support Google's event operations by building Apps Script workflows and data pipelines to validate and synchronize event and attendee data. I also develop lightweight internal tools, manage event audience and segmentation, and bring reporting and AI automation into day-to-day processes.

Dec 2024 — May 2026

Growth Horizon

Marketing Automation Developer

Built custom Klaviyo integrations for Lightspeed, Mijnwebwinkel, and Logic4, connecting customer history and events to email marketing workflows. Developed Google Cloud automations, sales intelligence pipelines, and internal tools for onboarding, invoicing, revenue tracking, and performance analytics.

May 2024 — May 2025

PriceShape

Business Development Representative

Generated appointments across Northern Europe and Spain in English and Spanish, using outreach data to refine sequences and follow-up. Built Looker Studio dashboards for lead quality, hit rates, and no-shows, while improving prospect data and automating softphone reporting.

Business foundations. Technical depth.

M.Mgmt. in Agribusiness, Lincoln University (Merit) · B.Sc. in Finance, Universidad Americana

Certifications & continued learning

Agentic AI
Generative AI Leader Certification
Gemini for Google Cloud Learning Path
BigQuery for Data Analysts
Creating Business Value with Data and Looker
Applied Data Science Lab
Computer Science Career Path
Google Advanced Data Analytics Certificate
Data Analyst Professional Certification

04 / Let's build something useful

What's the thing
you wish just
worked?

A prospecting bottleneck, disconnected CRM, manual handoff, or data you can't get answers from. Tell me what you're working on.

WhatsApp ↗LinkedIn ↗

Hiring for a sales engineering, GTM systems, MarTech, or data automation role?
Get the full CV

Less busywork.More business.

Real problems.Working solutions.

growth-metrics.

One workspace.Fewer operational handoffs.

Your sales calls.Searchable through an agent.