Hands-on E-Commerce & D2C Consulting

Revenue stalling. Operations breaking.
Too much manual work. No e-commerce expertise in-house.
I work alongside you to fix that.

S-GRIT is a consulting and business support firm specialized in e-commerce, D2C, and DX strategy. I don't stop at strategy decks — I get into the details: business design, EC/digital PM, agentic AI adoption for operational efficiency, Shopify builds, operational improvement, and team development. Not slides from a big consultancy, but hands-on expertise from someone who has led businesses firsthand, driving your business forward together.

Thoughts

Perspective Notes

Claude Code Is Not a "Coding Tool" — It Rewrites How You Work → The "Zero Reset" of Competitive Advantage in the Age of Generative AI → Why CDP/CRM Projects Fail to Deliver → What "Proposal Capability" Really Means for EC Vendors → The Rise of the Creator Economy → How to Bring International Tourists to Your Town →

Profile

20 years in e-commerce operations. You work directly with me.

Shinnosuke Mizuno

Founder, S-GRIT LLC

After earning an MBA from Dartmouth's Tuck School of Business and working at a strategy consulting firm, I spent two decades building and scaling e-commerce and D2C businesses across consumer goods, entertainment, and outdoor industries.

At a global music company, I led the e-commerce division, managing merchandise for thousands of artists across official EC stores built on Shopify. I also expanded cross-border EC operations for artist official stores. I relaunched a heritage German outdoor brand into the Japanese market from scratch. Most recently, I've been advising a Shopify Premier Partner on business strategy and serving as PM for a B2B site launch project.

The common thread: I've always worked on both strategy and execution. S-GRIT's strength is the ability to speak with equal depth about upstream planning and the messy realities of day-to-day operations.

  • MBA, Tuck School of Business at Dartmouth
  • Strategy consulting background
  • Hands-on Shopify / Shopify Plus build and operations experience
  • E-commerce leadership across B2B and B2C
  • Fully bilingual (Japanese / English)

What I Do

What you can actually hire me for

No fixed service packages. I define my role based on your specific challenges. Here are the most common engagement patterns.

EC business launch or rebuild
"We want to start selling online but don't know where to begin." "Our existing EC isn't performing and we can't figure out why." From business model design to platform selection, Shopify build, and initial operations. Whether it's a greenfield launch or a turnaround, I cover it end to end.
Agentic AI adoption for operational efficiency
Supporting non-engineers with source code analysis and system renovation planning. Automating and streamlining individual business processes with AI. From hypothesis building and data preparation to management dashboard development — I bring AI into real operations to sharpen business visibility.
Shopify / Shopify Plus build PM
Struggling with the gap between your business team and dev vendors? I translate business requirements into Shopify architecture — requirements definition, development management, custom app PM. The more complex the requirements (B2B wholesale, global expansion), the more value I add.
D2C growth strategy
Revenue exists but has plateaued. Promotions are ad hoc with no strategy. Customer data is accumulating but unused. CRM design, promotional framework overhaul, channel strategy — I help you design the next move.
Operations improvement
Order processing, inventory management, customer support, fulfillment. Workflows that still depend on specific individuals even as the team grows. From tool selection to workflow design and team adoption.
Vendor strategy consulting
Business strategy and proposal capability for EC development vendors themselves. Enterprise project management. For vendors that can build but struggle to propose from a business perspective.

Cases

What I've worked on and what I delivered

Selected engagements, shared within the bounds of confidentiality.

Global Music Company, Japan

Head of E-Commerce
Challenge
The D2C business for physical products (CDs, vinyl, artist merch) was stuck in legacy mode with no clear path to transformation. Promotions were siloed by label with no unified strategy. Store operations were person-dependent with heavy reliance on a few key staff. Cross-border EC was untouched.
Actions & Results
Selected Shopify as the platform, expanded sales methods, and drove standardization of previously person-dependent operations while rebuilding the team structure. Systematized promotional playbooks and rolled them out across labels. Launched cross-border EC (primarily NA & Asia), generating $3.3M in year-one revenue.
+78% Revenue growth over 3 years
50+ Shopify stores managed
$3.3M Cross-border EC, year one
Shopify D2C Cross-border Operations

Major US Cap Brand, Japan

E-Commerce & Retail Director
Challenge
Joined as head of the entire DTC business (EC + owned retail). EC revenue was flat. Brand awareness was strong but traffic to owned channels was weak. No coordination between stores and EC — channels were cannibalizing each other.
Actions & Results
Overhauled the EC platform and drove CRM integration between stores and online. Introduced OMO initiatives to unify the customer experience. Opened new stores while revitalizing existing ones.
3.7x DTC revenue growth in 4 years
26%+ CAGR Annual EC growth rate
DTC Strategy OMO Retail CRM

German Heritage Outdoor Brand, Japan

Brand Director (Business Lead)
Challenge
Re-entry into the Japanese market. Existing brand recognition was skewed toward older demographics and needed repositioning toward millennials. Distribution, branding, and team — everything had to be built from zero.
Actions & Results
Rebuilt brand strategy from the ground up, anchoring on Japan-exclusive product lines with a revamped MD strategy. Negotiated with the German HQ merchandising team to roll out Japan-designed items globally, achieving cost reductions through scale. Established 4 owned stores, an EC channel, and 150+ wholesale accounts in 2.5 years. Successfully shifted the target customer segment.
0 → 4 Owned retail stores launched
150+ Wholesale accounts
2.5 yrs Time to full market launch
Brand Relaunch Greenfield Retail Wholesale

Major Entertainment Company, Apparel Brand

Retail / EC Lead (New Business)
Challenge
An entertainment company launching a new apparel brand. Needed end-to-end design and execution of the entire retail business including EC. Responsible for merchandising, store development, EC build, and logistics design.
Actions & Results
Drove everything from business planning to operations buildout. Grew the business to 14 owned stores and an online channel, reaching ~$7M in revenue within 3 years.
~$7M Business scale in 3 years
14 stores Owned retail locations
New Business Apparel Retail EC Build

Shopify Premier Partner Vendor

Strategy Advisor / PM
Challenge
Japan's largest Shopify Premier Partner had strong development capability but weak business-oriented proposals. Enterprise projects were growing complex and lacked business requirements leadership.
Actions & Results
Partnered with the leadership team to reshape org strategy and sales structure. Deep-dived into clients' business challenges and operational processes, led business requirements definition for large-scale engagements, bridged client needs and dev teams, and structured complex business requirements into actionable system specifications.
Business Strategy Shopify Requirements PM

Contact

Let's start with a conversation

You don't need to know exactly what you need yet. Share where you're stuck, and I'll help you figure out where to start.

Initial consultation is free. NDA available upon request.