Joni Kähärä +358-50-4952033

Tenderinlenkki 8 A 52, 00520 HELSINKI Finland


Joni (b. 1975) is a programmer, machinist, and dilettante from Helsinki, Finland. He has worked in the technology industry since 1997.

Some of the things that bring him joy in the professional context include, in no particular order:

  • Remote work. Open, preferably asynchronous, text-based communication. Lack of hierarchy.
  • Automating things that can be automated. Think Ansible, Terraform, Kubernetes, and Helm and Flux. And GitHub and GitLab workflows.
  • Keeping things observable with the likes of Prometheus, Alertmanager, and Grafana.
  • Troubleshooting weird and complex situations, especially ones revolving around networking.
  • Working with people possessing a built-in, sufficiently paranoid approach towards cybersecurity.
  • Working with services on “edge”, or in other words things that interface with the physical world. Also anything with tight latency requirements.
  • Writing readable, robust, and performant code (including tests) in Go or Python that doesn’t waste resources. Rust and C have their special time and place, too.
  • ^That being said, sometimes a quick hack with no polish is good enough.
  • Working with domain specialists.
  • Writing readable documentation (Markdown, Pandoc preferred). Also technical writing in general, and reading anything well-written. Properly thought out diagrams always a huge plus.

Work Experience

5/2024 – Datalounges Oy

  • Senior cloud engineer

10/2023 – 4/2024 Taking a little break from work and looking around while at it

11/2019 – 10/2023 Advian Oy

A variety of projects, including:

  • Q4/2020 – Q1/2022 Digirata positioning backend project
    • Day to day work consisted mostly of herding AWS machinery in general and Kubernetes (EKS) machinery in particular, and coding microservices in Go
    • Services’ development is supported by, and they’re deployed with GitHub Actions-based workflows. Kafka (MSK) is the backbone.
  • Q1/2022 – Q2/2023 Systems herding as an external at RELEX
    • Development of microservices in Go and Rust
    • Testing and deployment automation, including GitLab pipelining
    • General Kubernetes (AKS) work, including enhancing the observability and cybersecurity situations
    • Plenty of troubleshooting, a lot of it related to Kafka

2/2018 – 11/2019 CGI Suomi Oy

  • Member, Video Analytics

9/2015 – 2/2018 Webmie Oy

  • Developer (Python, etc.)

4/2014 – 3/2015 Flatiron Software & Systems

  • An attempt to run my own software business, burning through savings and credit in the process
  • Key lesson learnt: don’t expect anything to happen without active sales

4/2011 – 3/2014 Visi-Systems Oy

  • Volumetric cargo measurement system utilizing a LIDAR and RFID tagging of bulk containers
  • Visitor counting system for pedestrian and vehicle traffic, utilizing “traditional” and machine vision sensors
  • A web/SMS-based paging system for fire personnel dispatch
  • A wall-climbing, (magnetic) wheeled inspection robot
  • Various smaller software development projects

2/2003 – 3/2011 Visi Oy

  • Physical access control/video surveillance system (the same project as below, company split in two)
  • Numerous smaller software development projects, including embedded things
  • Numerous hardware and software integration projects, mainly in the area of physical security and video surveillance

11/2000 – 1/2003 Visi-Systems Oy

  • Various web front ends for industrial data logging systems
  • Physical access control/video surveillance system; this evolved from Visual Basic 6 through C/GTK+ to a web-based system; actual hardware controlled included various gate control systems, video matrices and programmable logic controllers
  • Numerous smaller software development projects, including embedded things

1/1998 – 9/1998 Cardinal Information Systems Oy (Company bankrupt)

  • Maintaining ActiveX (C++) code of an early micropayment system
  • Maintaining server-side Javascript code of a press release service (early days of SaaS)
  • Various web site development and maintenance assignments

1/1997 – 10/1997 Top Information

  • Developing software (Delphi, C) and iButton-based electronics for a physical access control system

Language skills

Finnish: native

English: fluent (spoken and written)


Tinkering with electronics and radios is fun, too.