$ whoami
$ cat role.txt
Software Engineer in Test / Test Automation & QA
I test complex backend systems, platforms and APIs - building the automation, tooling and performance pipelines that let teams ship with confidence.
// function about()
I'm a Software Engineer in Test with over a decade of experience testing complex, distributed backend systems - from marketing-data platforms and fintech services to a global blockchain network. My focus is the unglamorous work that makes releases trustworthy: end-to-end and API test automation, performance profiling with regression tracking, and the tooling and CI pipelines that hold it all together.
For the past several years I've worked on Cardano at Input Output Global, owning release validation for core components and building automation that runs across multiple blockchain networks. I'm comfortable going deep - reading the product's source to find a root cause, generating millions of test vectors at scale, or writing the script that turns a day of manual work into a one-click pipeline.
I have a strong programming and computer-science background (MSc in Technical Physics), I'm a quick learner, and I genuinely enjoy the craft - clean tooling, reproducible results, and quality you can actually measure.
// const principles = [
Automation exists to buy back time for the part that needs a human - deciding what's worth testing and why. A pipeline nobody understands is just faster noise, so I build tooling that's documented, reproducible and boring to operate.
A bug you can't reproduce is a rumour; a number you can't reproduce is an opinion. I pin environments, capture inputs and make results repeatable - that's what turns "works on my machine" into something a team can actually act on.
"It feels faster" is not a result. Baselines, historical tracking and regression detection turn gut feeling into evidence - and catch the slow drift that no single test run would ever reveal on its own.
The quickest route to a real fix is often the product's own code, one layer deeper than the bug report suggests. I'd rather spend an hour reading the source and find the root cause than ship a workaround that quietly hides it.
I use AI the way I use any sharp tool - to clear drudgery, explore faster and pressure-test my own thinking - rather than resisting it. The engineer still owns the judgement, the review and the accountability; AI just gets me to the problems that actually matter sooner.
];
// git log --career
// ls ./selected-work
On the Midnight Glacier Drop, I automated signed claim-payload generation across Bitcoin, Cardano, Solana, XRP and more. Designed for parallelism and batching, and re-engineered with streaming I/O to break Node.js memory limits on datasets that defeated the original approach.
Validated an ETH integration feature end-to-end: USDC and xReserve smart-contract flows, wallet data handling (Cardano address extraction, MetaMask balance checks) and EVM gas-fee logic for approve/deposit calls, including dark/light branding.
Primary QA owner for the CLI and stake-pool functionality through the Friends & Family testnet and the Shelley mainnet launch - transactions, delegation, pool registration and retirement, and metadata. Built the first test-automation framework for these flows and validated every official Stake Pool tutorial. Found and fixed a critical fee-parameter ordering bug deep in the CLI.
End-to-end release validation for cardano-db-sync: full syncs from clean state, snapshot creation and restoration, and CPU/RAM/sync-time profiling with historical regression detection across preview, preprod and mainnet - plus root-cause fixes contributed upstream to the product itself.
Designed reusable test services and automated coverage in the cardano-node end-to-end framework - including a db-sync snapshot service with freshness checks and full SMASH service support for integration testing.
Automated validation of Conway-era governance and configuration-dependent behaviour: protocol-parameter update proposals (CIP-0080 -> CIP-0083), treasury donations and withdrawals, and conditional governance-event processing in db-sync.
$ git log --author=ArturWieczorek --merged -n 10 // newest first
// cat toolbox.json
// ls ~/open-source
// echo $CONTACT