whoami
Daniel Kubitza
Team Lead Development · mailbox.org / Heinlein Support
I build autonomous, cross-functional teams that do their best work even when I'm not in the room. That is servant leadership to me: shielding people from the daily madness so they can protect their focus, with ways of working that actually fit. Great software is never a tech-only story. It takes product and tech as equals, side by side in the daily work. And change only counts when it lasts: lived, reviewed, and adapted in PDCA cycles, until silos give way to collaboration and innovation.
// About
INIT_PROFILE
Starting as a software engineer in 2001, I grew into leadership roles driven by a genuine
interest in people and systems. I've led individual contributors, team leads, and entire
product areas, and the same principle holds at every scale: trust people,
give them clarity, and then let them work.
My engineering background keeps me close to the work. I can read the code and question
an architecture, but my job is to lead people, not commits.
Currently leading development at
mailbox.org, the Berlin-based secure mail and office service of the
Heinlein Group: privacy by design and open standards. With a clear mission:
digital sovereignty for Europe.
// Experience
XP_LOGMoved the team from parallel backlogs to focused, cross-functional delivery: the mailbox.org brand relaunch shipped hand in hand with a switch of the entire technical backend, without work going stale between teams. Our first fully cross-functional team then took EVAC from a real discovery phase through fixed-team sprints, with reviews and retros, to launch. A model we are now repeating for the next products. The difference shows: fewer context switches, fewer cross-team blockers, shorter lead times.
As part of the mailbox.org leadership team, driving OKR adoption with methodical workshops that turned reliability and growth ambitions into few, sharp objectives with first measurable results.
Now driving AI adoption in engineering: building on GitHub Copilot and introducing Junie to lift delivery throughput, then adapting the processes around it, from code review and refinement to incident post-mortems. When development speeds up, the bottleneck moves elsewhere, which only sharpens the point that product, technology and operations have to scale together.
Early OKR adopter at STRATO: my team was among the first to pilot the framework, helping shape the company-wide introduction.
We re-cut the product area around domains: Merchant Business owning the entire merchant journey, from onboarding via sales and Salesforce or our self-service tools to invoicing the shops, while the new Inventory unit focused on the massive data import that keeps prices on idealo current by the minute.
In the leadership circle under CTO and CPO, set unit OKRs and co-authored idealo's guiding principles, with #domain-driven and #end-to-end-responsibility as my focus.
When the pandemic hit, we switched fast: physical whiteboards turned digital, processes adapted, and we worked deliberately to keep the human connection alive in the new hybrid culture.
Together with the Head of Product, established English as working language and invested in people's language skills, opening hiring to a far larger talent pool. idealo product & technology later made English official.
Established a real leadership routine of team leads and POs together with product, and turned tool-based silos into product teams. A new fourth team, grown from shop administration members plus new experts, replaced home-grown CRM functions with Salesforce, bringing the unit to 4 teams and 25+ employees.
When the C-level opened a call to rethink the B2B structure, my proposal, sharpened in conversations beyond my own area and backed by two of my team leads, was adopted: two focused B2B units instead of three, the blueprint for Merchant Business.
Built and hired the entire engineering team from scratch: 5 backend developers, frontend, DevOps, QA and a product owner, including former colleagues who chose to work with me again. Set up delivery from scratch with Scrum and its ceremonies.
Together we automated the core of the business: boxes of mail from authorities arrived every day, formatted differently in every German state and typed in by hand. OCR capture, tailored to each state, fed the data straight into the CRM. Several people no longer spent their days on manual data entry, and input errors dropped: a small gain per case, a massive one at volume.
Led a core development team of 6+ engineers and repeatedly took full technical responsibility for new ventures as Project CTO: 100 days from kickoff to soft launch. Then continuous build-out around what the market actually needed, until the venture's own team took over development.
In between, my team ran Rocket's own web presence and quietly prepared it for the IPO.
// AI in Practice
HUMAN_IN_THE_LOOPAI changes how developers work, so the processes around them have to change too, without losing sight of the people doing the work. Bottlenecks move: when development speeds up, definition and operations have to keep pace. That is where I focus.
GitHub Copilot and Junie in daily development, with code review and refinement adapted to more AI-assisted code.
Part of how we follow up on incidents, refined round by round and shaped together with the colleagues who run them.
Generated from what the code actually does, so product knowledge doesn't live in just a few heads and the definition gap narrows.
Open-source, self-hosted bookshelf. Scan a barcode, metadata and cover land locally, runs on plain shared hosting. Live · Code
A book-addiction quiz for my wife's blog buecherhausen.de. Anonymous statistics without personal data, shareable results. Live
Voice assistant for the family: speech recognition and voice stay local, only the "brain" runs in the cloud.
A circle that breathes with you. Works offline, and deliberately nothing else. Live · Code
All built with AI coding agents. That is how I learn where agents speed things up, and where review and judgment still carry the weight.
// Skills
CAPABILITIESnever done learning
// Learning & Development
TRAINING_DATA// Voices
TESTIMONIALSvoices from the people I've worked with
He encouraged ownership, created clarity when needed, and always treated people with respect. A thoughtful, supportive leader who helped me grow professionally.
Benjamin Schulz
Team Lead Mobile Apps @ idealo · former direct report
He always stood up for his team in difficult situations. A calm person who makes sustainable decisions, and never ignores the people around him.
Sascha Perkowski
CTO · former direct report
He truly cares for the people in his team and goes beyond technology, diving deep into matters of the organization and the product. A thoughtful, holistic tech leader, and genuinely fun to work with.
Gerrit Lutter
Senior Agile Coach @ MOIA · Agile Coach in my team at idealo
Most of the business pressure was suppressed by Daniel, so the team could fully concentrate. The best team lead I have worked with.
Inokentii (Kesha) Golovin
Engineering Manager · former team member