Kosei Taki is an independent developer and former IT consultant. From 2012 to 2023 he worked at an enterprise IT consulting firm on core-system and digital-strategy projects, and he has worked independently since 2023.
After working in consulting, he transitioned into freelance work, focusing on building and managing projects as a solo operator. Through this shift, he experienced a gap between how software is presented and how it is actually used by individuals:
- pricing that scales unexpectedly
- features designed for teams rather than solo users
- "free plans" that become restrictive in real workflows
SoloStack was created to bridge that gap.
Instead of reviewing tools from a corporate or team perspective, Kosei looks at them from a solo freelancer's point of view — balancing cost, flexibility, and long-term usability. His approach combines:
- hands-on use of some tools, stated explicitly in the article where it applies
- analysis of pricing structures and limitations
- practical decision-making from a freelancer's perspective
Not every tool is used long-term, but each review focuses on the points that matter most when choosing software independently.
Day to day, SoloStack is written around client work rather than instead of it — most weeks it's client projects first and writing in whatever's left over, which is also exactly the kind of scheduling tension the site's own reviews are written for. In consulting, the work was less about comparing features than about whether a system would actually be usable by the people running it, what it would cost to operate after rollout, and whether the cost was justified. That way of weighing a tool carries over to how SoloStack compares software.
Background
2012–2023: IT consultant at an enterprise IT consulting firm. Representative work is described by scale and duration only, because client details are confidential.
- Core-system renewal support — a system used by several hundred people, over a year or more. Current-process analysis, requirements definition support, vendor coordination, and test and migration planning.
- Retail and distribution system rollout support — dozens to hundreds of sites, roughly six months to a year. Stakeholder interviews, business-flow mapping, requirement prioritization, and operations design support.
- Digital strategy and data utilization support — an initiative spanning several departments, roughly six months to a year or more. Issue framing, KPI design, data analysis, and support for measuring the effect of measures.
Credentials (IPA, Japan): Information Security Management Examination, passed 2018; IT Strategist Examination, passed 2022.
Tools Kosei uses himself: Google Workspace, Money Forward Cloud, Dropbox Sign, Upwork, Notion, Slack, and Discord. Not every tool reviewed on SoloStack was used in client work, so first-hand use is stated in the articles where it applies and is kept separate from pricing and feature research.
Featured in
- 25 Legal Challenges Faced During Business Formation and How to Overcome Them — Connectively (Aug 2026)
- Crucial Lessons Learned in Year One: Advice from Entrepreneurs — Grit Daily (Oct 2026)
- How Freelancers Raise Rates With Confidence — GIGS Magazine (Oct 2026)
More on how the site works
For the specific criteria used in each comparison and where the underlying information comes from, see the Methodology page. For how this site is funded, see About SoloStack.