Shun Matsubara松原 舜 · Tokyo
A marketer who has moved real numbers in ads, social and SEO, now building and running it all with AI.
- Co-founderNexAI (incorporating) / Employee Store
- FounderSTAMP / HOOK CLUB (student orgs)
- ContractAI, care-sector marketing and 3 more
Monthly Meta/TikTok ad spend managed
ONE · 2025.10–2026.05ROAS on my accounts
RASA JAPAN · 2025Men’s beauty Instagram followers, from 1K in ~8 months
セスグモ · 2025Views on one AI drama episode (2 days)
YouTube · 2026-11-14NowWhat I’m doing now
Running my own ventures and student orgs alongside contract marketing and AI work. Clients are described by industry.
NexAI / Employee Store
STAMP / HOOK CLUB
An AI implementation firm
A care-sector marketing firm
3 more clients
Official AI-tool ambassador
WorksSelected work
From vertical AI dramas to a 10-minute explainer. Hover to play.
CareerCareer
Economics student at Hosei University. Since 2024 I’ve worked with 10 companies across HR, ads, social and e-commerce, owning both strategy and execution.
ONE Inc.
¥30M/mo ad spend~50-person org
ABABA Inc.
27K+ sessions/mo on target pages
Athena Technologies
clout Inc.
Hero SKU +250% YoY
SIXTYPERCENT Inc.
RASA JAPAN Inc.
ROAS 200%→800%
Sesugumo Inc.
1K→38K followers
Mercari, Inc.
GMO NIKKO Inc.
SHiRO Inc.
Booking rate 20%→35%
AI systemsThe systems I run with AI
Not just building: I own the systems that keep it running every day. All figures are measured.
Always-on automation jobs
Posting, metrics, replies and SEO run as launchd jobs: 240 on a MacBook, 121 on a Mac mini.
launchd · 2026-11-14Commits in 6 months
May–Oct 2026 across 144 repos. Claude Code and Codex implement; I design and verify.
git · 2026.05–10Social accounts on 2 phones
Genre channels posting daily from two Android phones via adb.
fleet · 2026-11-14Wiki pages my agents read
Decisions, mistakes and playbooks, plus 437 custom skills, loaded into every task.
Obsidian · 2026-11-14Measure what works
Collect what’s growing; count length, cuts and the first two seconds.
Turn it into a format
Turn the counts into rules; lock characters and look.
Build with AI
Images, video, voice and code, each with the best tool for the job.
Fix with numbers
Read the numbers after publishing, fix the next one, automate the loop.
AI
- Claude Code
- Codex CLI
- Gemini
- ElevenLabs
- HeyGen
- Higgsfield
- Renoise
- Kling
Video
- Remotion
- FFmpeg
- Blender
- Three.js
- CapCut
- HyperFrames
Dev
- TypeScript
- Next.js
- React
- Hono
- Cloudflare Workers / D1
- Supabase
- Stripe
- Python
Ops
- launchd
- Android + adb
- GA4 / Search Console
- Ahrefs
- Obsidian
- Figma
ProductsThings I’ve built
Services I took from idea to build, launch and growth.
Employee Store
LiveA marketplace to find and hire AI agents as “AI employees”, payment to delivery on one site.
employeestore.app ↗Day91
LiveA job board of paid long-term internships with a retention bonus on day 91.
day91.jp ↗crefi
LiveMatches creators who allow affiliate links with partners who promote them.
crefi.jp ↗STAMP
RecruitingAn inter-college student org for working with the world from Japan.
stamp-students.com ↗HOOK CLUB
LaunchingA student-only social and short-video production collective.
hookclub.jp ↗Dot Dungeon
LiveA 2-minute pixel RPG with a new dungeon every midnight.
dot-dungeon.pages.dev ↗AccountsAccounts
I’m @ummshun. I also run the AI account “Lily” (@bokuwalily). Followers as of 2026-11-14.
Official AI-tool ambassador: HeyGen (1st cohort) · AIReel · TANKA · Manus
Let’s move the numbers,
and build the system behind them.
I help with hands-on social, ads and SEO, and with AI production and automation. DM me on X or email.