About
Execute. Done.
An AI Business Operating OS for solo founders.
Costart builds an L1 AI Business Operating OS, applies it to our own business, validates it on real revenue, and hardens it through verticals, teaching, and consulting.
12 live products · 4 languages · one-founder operations
STAR-T’s journey for local revitalization →Not claims. URLs.
Every one of these opens live, right now. Only dogfood-passed products are sold externally.
AI executes. Humans decide.
Help solo founders / builders full-stack, at every stage from idea to lifestyle, in the AI era.
The first Korean reference at the AI × XR intersection, and the backbone of the solo founder community.
Verify, accumulate, and own AI output. Source, hallucination flags, and audit logs are baseline.
No shallow wrappers. Build at least two moats per domain.
If the founder ain does not use it on their own work, we do not sell it.
We name what we cannot do (e.g. Korea-only tax scope, LLM accuracy limits).
AI works, ain decides. Six-hour daily operating rule.
Models · Data · Infra.
- GPT-5 · Claude Opus / Sonnet · Gemini 2.5
- Gemma 3 4B · local fallback (Ollama)
- OpenAI text-embedding-3-small
- Router: cloud / hybrid / local
- PostgreSQL + pgvector (IVFFlat)
- tax_ai RAG 실가동 · 법령 OPEN API 자동수집
- Append-only ledger
- decisions · executions · outcomes · source_claims
- Next.js 16 · App Router · 4-lang i18n
- Vercel Fluid Compute · Cron · MCP
- GitHub Actions · typecheck · test gate
- 관측: GA4 · source_claims · KPI cron
L1 / L2 / L3 / D.
Every product is built and operated on the L1 OS.
AI business operating OS for solo founders. Threads dev, funding, marketing, ops, tax, QA, analytics.
L1 principles applied to a founder’s endurance: body, food, motivation, memory, relationships.
External vertical AI products, actually built and validated on L1. Only dogfood-passed products ship.
Discovery candidates testing untapped vertical AI markets on top of L1.
Business A→Z, 11 stages.
| Stage | Product | Description |
|---|---|---|
| 01Opportunity | AI MVP Builder Live | Structure ideas and market hypotheses into a business shape. |
| 02Product | AI MVP Builder Live | Lean Canvas, PRD, MVP scope. |
| 03Funding | BIDS Live | Recommend & draft against G2B / K-Startup / regional grant calls. |
| 04Marketing | AI-MARKETING · Auto Blog Live | Trend → generate → publish → UTM. Runs solo. |
| 05Sales | Sales CRM OS Internal | Deal briefs, ICP scoring, handoff tracking. |
| 06Build | AI-SYSTEM (ai-kit) Live | Lock decisions → build MVP → verify deploys. Every product is built on this. |
| 07Quality | QA 진단 도구 Planned | AI output diagnostics, hallucination flags, regression gates. |
| 08Finance & Tax | TaxPro-KR · Billing OS Live | Korean tax law with source-traceable RAG (live) + internal billing pipeline. |
| 09Customer Success | CS 운영 대시보드 Planned | Structure support data, track operational improvements. |
| 10Analytics | Analytics OS Internal | OS/agent performance analysis, KPIs, promotion candidates. |
| 11Compliance | Compliance Gate Internal | Constraint rules + secret-scan gate (HITL). |
Live = sold externally · Internal = in daily use inside our own OS · Planned = pre-release. All 11 stages have an execution slot.
Design → apply → verify → re-harden.
One founder + an AI agent team.
An 11-agent system is designed; the core agents run daily while the rest roll out in stages. The system does not stop when the founder steps away — a 07:30 operations brief ships every day, sales follow-ups track automatically, proposals draft on demand.
| Codename | Role | Domain | Cadence |
|---|---|---|---|
| tae_ops | Ops Lead | Portfolio operating state | Auto · daily 07:30 |
| soo_research | Research Lead | Market · policy · RFP analysis | On demand · auto |
| yuri_bizdev | Proposal Lead | Auto proposal & business plan drafting | On call ingestion |
| mina_cmo | Growth Lead | Marketing, content, channels | Content queue auto |
| hana_cfo | Finance Lead | Finance, revenue, cost summary | Monthly auto |
| jin_cpo | Tech / Product Lead | Code diagnostics & product strategy | PR-triggered |
| memory_lead | Memory Lead | Info classification & ledger | Daily 23:30 auto |
| customer_lead | CRM Lead | Sales pipeline & follow-up | SLA-trigger auto |
| schedule_lead | EA Lead | Schedule, contacts, checkpoints | Weekly auto |
| research_intern | Research Intern | Primary source collection / crawling | Pipeline-linked |
| archivist_jin | Archivist | Retros & quarterly archives | Quarterly auto |
Build product and operations together.
모든 외부 발행은 source_claims.jsonl의 verified 항목만 인용합니다. 미검증은 [UNVERIFIED]로 표기합니다.
사용자가 직접 실행·승인합니다. 우리는 라우터·스킬·QA로 헛돌이를 줄일 뿐, 최종 책임은 사용자에게 있습니다.
요구사항 → MD Task 분해 → 라우터로 단계 강제 → 무단 진입 차단. AI가 헛도는 빈도와 영향을 시스템적으로 줄입니다.
펌웨어·HW 직접 개발 ❌, 공고 자동 큐레이션 ❌, 의료기기 SW(IEC 62304) ❌, 한국 외 세법 ❌, 외주 개발 ❌.
2020 — 2025, cumulative.
- 116건
- Lectures & consulting
- Repeated engagements, not one-off talks
- 1,000명+
- Total learners
- Educational design across a wide range of skill levels
- 35건
- Core B2B programs
- 2020–2025 accumulated curriculum operation
- 1,100건+
- Material & session evidence
- Structured material-driven sessions, not improvised
- 4.71/5.0
- Satisfaction
- Self-run surveys, tied to 1,100+ pieces of session evidence
- 4.68/5.0
- Recommendation
- Self-run surveys — repeated field-applicability feedback
- 4 consecutive years with Shinhan Financial
- Selected as a Modu Startup AI service provider
- B2G PoC with Eumseong-gun; Busan Global Fintech in progress
- tax_ai live: Korean-tax RAG (pgvector + statute API)
Teaching, consulting, collaborating.
Organizations we have taught, consulted, or collaborated with — including four consecutive years with Shinhan Financial Group.
2020 — 2026.
- 2020Lectures & consulting begin
Corporate lectures and government grant mentoring begin — start of the 116-engagement run.
- 2021–2022XR pilots / fintech build
XR pilots in Incheon and Seoul tourism. Fintech v1 with FSI / KFTC certification experience.
- 2023–2024Vertical builders accumulate
Vertical dogfooding starts: ko_living_ai (foreigner settlement), tax_ai (tax-law RAG), jodal (funding). 4 consecutive years partnering with Shinhan Financial.
- 2025AI OS in earnest / 25 products
L1 AI business operating OS hardens. 28 AI products (12 live) across 10 sectors run by one founder. Selected for Modu Startup’s AI service provider listing.
- 20269 businesses · AI agent system · B2G PoC
11-agent system designed with core agents running daily (07:30 brief). B2G PoC with Eumseong-gun (Chungbuk) and Busan Global Fintech in progress. invest (research), xr (XR Agent Builder), and care (CareSync) went live.
Founder
박정근 (ain)
Park Jeong-geun (ain). Fintech v1 founding with FSI/KFTC certification, XR pilots in Incheon and Seoul tourism, four consecutive years partnering with Shinhan Financial. Runs STAR-T solo on a six-hour-per-day discipline.
FAQ
- Do you take outsourced development?
- No. STAR-T is not an outsourcing dev shop. Our product line (e.g. AI-Developer-KIT) is designed so the founder ships the product themselves.
- How much teaching and consulting have you done?
- From 2020 through 2025: 116 engagements, 1,000+ learners, 1,100+ pieces of teaching material, satisfaction 4.71 and recommendation 4.68 out of 5.0, and four consecutive years partnering with Shinhan Financial.
- How big is the team?
- One human founder plus an AI agent team. An 11-agent system is designed; the core agents (operations brief, research, proposal drafting) run daily, and the rest roll out in stages. The 07:30 operations brief, automatic sales follow-ups, and on-demand proposal drafts continue even when the founder steps away.
- What do you not do?
- We do not build firmware or hardware directly, we do not auto-curate public funding calls, and we do not handle medical-device SW (IEC 62304) certification. We name our limits — for example, tax scope is Korea-only.
Costart Inc. (STAR-T) · Founder Park Jeong-geun · Incorporated 2024 (active since 2020)
No upsell — only what fits.
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