Mika Pesonen

• Integrated Sigfox LPWAN, collecting environmental data from tens of thousands of IoT devices, streamlining device setup, and contributing to a multi-million euro revenue stream.
• Integrated Metry.io API, collecting energy usage data (energy, water, gas, heating, cooling), enabling data use for billing, analytics, and usage alerts.
• Integrated internal building automation software ('Cream'). Collected and processed sensor data and tags, enabling data-driven analysis for hundreds of customers buildings.
• Integrated SharePoint, enabling customers access to building documents like maintenance, safety and escape plan records
• Collaboratively ported legacy ETL pipelines to a Databricks and Deltalake powered solution using the Medallion Architecture, improving data load times, quality, and enabling more complex analytics and data reprocessing capabilities by securely storing all raw data.
• Created and maintained customer-facing API documentation. Allowing hundreds customers easily integrate their data to the web portal
• Mentored new team members, joined planning meetings, worked with the Product Owner in customer discussions, and supported the technical negotiation of a company acquisition.

• Designed, developed, and maintained ETL pipelines and customer-facing APIs
• Ensured data quality with automated tests
• Developed a data processing pipeline using Python 3 and Pandas on Apache NiFi for daily competitor analysis
• Developed an AWS Lambda-based API for team access to current pricing information

• Implemented updates to customer's Android projects
• Designed and developed a demo of a room booking app
• Implemented Auth0 user account integration for a customer's app

• Maintained and updated the company's public API, ensuring functionality, performance, and reliability
• Implemented and maintained the company's API portal and collaborated with cross-functional teams
• Successfully ensured the continuous operation and reliability of the public API, supporting third-party integrations
• Developed and maintained an intuitive and user-friendly API portal

• Developed and maintained a native iOS doctor search application
• Implemented a map-based user interface and integrated third-party services like Google Analytics
• Developed and launched a native iOS application that improved performance and usability

• Developed and maintained the Good vs. Bad iOS mobile application
• Integrated iOS applications with Python-based back-end APIs and provided post-launch support
• Designed, developed, and launched the Good vs. Bad iOS application, integrating a Python back-end API and attracting thousands of users

Specialized in Information Technology and Telecommunications.

Combined resume and project portfolio. The very site you are currently browsing.

Website: React, Remix and TypeScript running on Cloudflare Pages.
AI data importer: written using Python 3 and LangChain JSON-importer.
AI: Mistral-7B-Instruct-v0.1 LLM with Retrieval-Augmented Generation (RAG) running on a Cloudflare Worker.

 Code available on GitLab.

Faced with the challenge of implementing support for Sigfox IoT devices within a two-month timeframe, I successfully delivered the solution in just over one month. I designed and implemented an automated ETL (Extract, Transform, Load) pipeline that extracted data from the Sigfox back-end, transformed it by processing and matching it with corresponding sensors, and subsequently loaded the data into the database.

This solution simplified the onboarding process to merely registering the device ID on the web portal. Over the next five years, the ETL pipeline demonstrated exceptional scalability, supporting hundreds of customers and tens of thousands of devices. It played a pivotal role in driving substantial business growth, generating millions in revenue while requiring minimal ongoing maintenance.