PRD v1.0Portfolio ExerciseB2B2C · Hardware SaaS · India

KartMetrixProduct Requirements Document

Disclaimer: This is a technical PRD exercise demonstrating B2B2C product thinking, hardware integration complexity, and SaaS unit economics. KartMetrix is not a company being built — the Indian karting TAM (~120 tracks) makes this non-venture-scale. The value is in the reasoning.

Executive Summary

Indian go-karting tracks are infrastructure-rich and data-poor. Venues across Delhi NCR, Bangalore, Mumbai, and Pune have RFID/transponder timing systems installed — but the data they generate never leaves the timing box. Track operators manage revenue on gut feel and Excel sheets. Drivers receive a paper lap slip after each session with no digital trail.

The solution in one sentence

KartMetrix sits between timing hardware and business intelligence — a B2B SaaS for operators (revenue analytics, dynamic pricing, driver LTV) and a B2C app for drivers (lap history, leaderboard, sector times), connected by a flywheel where engaged drivers drive repeat sessions that increase operator revenue and willingness to pay.

Stakeholder	Role	Success Metric
Track Operator	Paying B2B customer	Revenue uplift, utilisation % improvement
Competitive Driver	Free B2C user	Repeat session rate, app engagement
KartMetrix	Platform	MRR retention, CAC recovery timeline

Jobs-to-be-Done

Operator JTBD

“Help me understand which hours are profitable and which drivers are worth investing in so I can run a tighter operation.”

Functional

·Know real-time session count and revenue without calling the cashier
·Identify underutilised time slots and price them accordingly
·Understand which drivers are regulars with high LTV vs. one-time visitors
·Get notified when a regular driver hasn't returned in 30+ days

Emotional

·Feel like a professional operator, not a family business running on instinct
·Have data to justify pricing decisions to partners

Driver JTBD

“Show me how I'm improving over time and let me compete with other regulars at my track.”

Functional

·See lap times and sector splits after every session, on my phone
·Compare my best lap to other drivers at this track
·Track improvement over time — is this week better than last month?
·Share a good lap time with friends

Emotional

·Feel like a real racer, not just a weekend leisure driver
·Have a reason to come back before I forget how close I was to the track record

Technical Architecture

Hardware (pre-existing at track)

RFID induction loops embedded in track surface. Transponders in each kart. Timing unit: AMB Chronolap or MyLaps RC4 (most common in India). Output: raw crossing events — [kart_id, loop_id, unix_timestamp_ms].

⚠ ~60% of target tracks already have RFID installed. No hardware replacement required.

Edge Device (KartMetrix installs)

Raspberry Pi 4B. Connects to timing unit via RS-232 serial port. Go daemon parses AMB/MyLaps serial protocol, normalises events, buffers to SQLite during outages, forwards via MQTT QoS 2. 4G SIM fallback for connectivity.

⚠ AMB and MyLaps use proprietary serial protocols. Serial bypass avoids per-crossing API fees.

Cloud Pipeline

Edge → MQTT Broker (AWS IoT) → Event Processor (lap calculator: consecutive crossings → lap time) → PostgreSQL → REST + WebSocket.

⚠ Lap time calculated and pushed to dashboard within 500ms of crossing. WebSocket updates every 2s during live sessions.

API Layer

REST API via Next.js API routes for the operator dashboard. WebSocket via Socket.io for the live session feed. Authentication: JWT scoped per track. Rate limiting: 100 req/min per track API key.

⚠ Track-scoped auth (not per-user) reduces operator onboarding friction at the cost of granular access control.

Operator Dashboard

Next.js App Router deployed on Vercel. Recharts for data visualisation. Mobile-responsive for pit-lane use. Auth-gated per track. V1 shows exactly 4 numbers: sessions, revenue, utilisation, top driver.

⚠ Operator tech literacy is a critical risk. Dashboard complexity must stay minimal.

Driver App (PWA)

Next.js PWA delivered via WhatsApp link post-session. No app store required. Shows personal lap history, track leaderboard, sector times. Optional 'Add to Home Screen' for repeat users. WhatsApp Business API for push.

⚠ WhatsApp-first beats email or push notifications for Indian demographic. 84% opt-in rate in Indian market.

Lap calculation logic

// A lap = consecutive crossings of start/finish loop by the same kart
lap_time_ms = current_crossing.timestamp_ms
            - previous_crossing.timestamp_ms
            // where: same kart_id, same loop_id (SF)

// Sector time = time between sector loop crossings
sector_time_ms = sector_loop_crossing.timestamp_ms
               - start_loop_crossing.timestamp_ms

// Session = group of laps within a booking window
// flagged by operator (start/end button on dashboard)

Feature Prioritization

✅ V1 — Pilot-ready (Month 0–3)

Session analytics dashboard

Core operator value prop — immediate ROI. Replaces gut feel with numbers.

Daily / weekly revenue summary

Replaces WhatsApp cashier reports. Builds the daily-check-in habit.

Session utilisation heatmap

Visual trigger for the pricing conversation.

Driver leaderboard (per-track)

Primary driver retention hook. Social competition drives repeat sessions.

WhatsApp lap-time delivery

Zero-friction driver activation. No app download required.

Basic driver profiles

Foundation for LTV scoring in V2. Needs 90+ days of history first.

🔵 V2 — Post product-market fit (Month 4–9)

Dynamic pricing engine

Needs V1 utilisation baseline. Biggest operator revenue unlock.

Driver LTV segmentation

Enables win-back campaigns. Requires 90+ days of session history.

Sector time analysis

RaceFacer parity for enthusiasts. Requires sector loop infrastructure.

Win-back WhatsApp alerts

Automates "driver hasn't returned in 30 days" outreach.

Championship mode

Adds session density. Needs operator engagement to configure.

Kart health dashboard

Maintenance alerts from lap time variance per kart. Needs V1 baseline.

❌ Descoped — and why

Multi-track franchise support

Smaaash locations are operationally independent. Cross-track analytics adds API complexity without V1 value.

White-label driver apps

N custom apps = N maintenance burdens. One KartMetrix brand builds driver CAC via word-of-mouth.

Global cross-track leaderboard

Meaningless without kart/track normalisation. Needs sector data standards first.

Race replay / video sync

Camera hardware + high storage costs. Out of scope until Enterprise tier validates demand.

Monetization Model

	Starter	Pro	Enterprise
Monthly fee	₹4,999	₹9,999	₹19,999
Setup fee (hardware)	₹80,000	₹80,000	₹80,000
Target sessions/month	40–80	80–150	150+
Track gross revenue	₹32–64K	₹64–120K	₹120K+
Platform fee as % of revenue	7–15%	8–15%	~13%
Hardware payback	18 months	9 months	5 months
Year 1 target (of 40 TAM)	8	14	6

Unit economics — Pro tier, 120 sessions/month

Track gross revenue₹96,000/month

Platform fee (MRR)₹9,999 (~10.4% of gross)

Hardware install (one-time)₹80,000

Hardware payback period~9 months

KartMetrix gross margin~70% (hosting, MQTT, WhatsApp API)

KartMetrix CAC~₹40,000 (field sales + install)

CAC payback period~4 months

Hardware strategy: KartMetrix sources and configures Raspberry Pi edge devices (~₹8,000) and RFID readers (~₹15,000). The rest of the ₹80K install cost is partner electrician fees and cable infrastructure. Margins on hardware are thin by design — SaaS is the business.

Go-to-Market Strategy

Indian go-karting is a relationship business. Track owners know each other. The GTM strategy uses a single successful pilot to generate peer referrals across city markets — field sales at the start, word-of-mouth at scale.

Phase 0 · Pilot

Month 1–2

Sign one anchor track per city at 50% discount in exchange for testimonial rights. Target: F9 Go Karting (Gurgaon), Meco Kartopia (Bangalore), Ajmera IndiKarting (Mumbai), Pune Kartdrome. These are the most visible, highest-volume tracks in each city.

Phase 1 · Proof

Month 3–6

Document revenue uplift at pilot tracks. Package as operator testimonials. Use pilot operator introductions to close the next 5–6 tracks per city via field sales.

Phase 2 · Scale

Month 7–18

Expand to Chennai, Hyderabad, Ahmedabad. Target multi-location operators (Smaaash, High Octane) for Enterprise contracts. Driver app WhatsApp shares generate inbound operator interest.

Competitor	What they do	KartMetrix advantage
MyLaps software	Timing display + basic session logs	Revenue analytics, dynamic pricing, driver app, WhatsApp
AMB built-in	Lap timer display only	Everything above
RaceFacer	Full telemetry platform (EU/US focus)	India-specific: WhatsApp, INR pricing, local support
Excel + WhatsApp	Current "system" at 90% of tracks	Anything automated

Success Metrics

🎯 North Star

Track Operator MRR Retention Rate

Target: >90% net revenue retention at 12 months. An operator who sees revenue improvement retains. If operators churn, the product isn't delivering measurable value.

Metric	Target	Why it matters
Session utilisation %	+15% in 90 days	Primary operator ROI signal
Driver app DAU/MAU	35%	Engagement flywheel health
Avg revenue per driver	+8%/quarter	LTV trend as pricing engine activates
WhatsApp opt-in rate	>75%	Driver notification reach
Time to first insight	<2 hours	Onboarding quality
Driver repeat rate (14-day)	>42%	Core business outcome

Risk Assessment

Small TAM

Critical

India has ~120 commercial karting tracks. Even 50% market share at Pro tier = ₹60L ARR — not venture-scale. Right vehicle: bootstrapped, profitable micro-SaaS. This is the primary reason KartMetrix is a portfolio exercise, not a company.

Hardware vendor lock-in

High

MyLaps charges per-crossing API access fees. If they change pricing, the cost model breaks. Mitigation: edge device reads RS-232 serial output directly, bypassing vendor API where possible.

Installation complexity

High

Every track has a different physical layout, timing unit model, and connectivity situation. Each install is bespoke — caps growth velocity and makes the install team a bottleneck. Mitigation: standardised edge device config, plug-and-play setup wizard, regional install partners.

Operator tech literacy

Medium

Track owners are often family business operators, not tech-forward. Dashboard complexity = churn. V1 dashboard is deliberately limited to 4 numbers. Complexity added only when operators request it.

Driver app cold-start

Medium

Empty leaderboard = uninteresting app for new tracks. Mitigation: pre-seed leaderboard with historical timing system logs on day 0.

WhatsApp Business API dependency

Low

Meta policy changes or cost increases affect unit economics. At 120 sessions/month, cost is negligible (~₹2–3/message). Build native app as long-term alternative.

Track Database — Phase 1

40 verified Indian karting venues across 4 cities (10 per city). Year 1 target: sign 28 of these 40 tracks. Used for illustrative portfolio purposes only.

Delhi NCR

Track	Location	Tier	Type
F9 Go Karting	Sector 17/18, Gurgaon	Pro	450m outdoor multi-level
F9 Go Karting	Sector 59, Gurgaon	Pro	700m outdoor circuit
F9 Go Karting	Sector 68, Gurgaon	Pro	1050m outdoor — longest in NCR
Smaaash Sky Karting	Sector 29, Gurgaon	Pro	Rooftop indoor track
Kartomania	Entertainland Mall, Sector 83, Gurgaon	Starter	Indoor mall
Formula Karting	Sector 38A, Noida	Pro	Near Great India Place Mall
Wonder Speedway	Worlds of Wonder, Sector 25, Noida	Starter	Amusement park
Forza Go Karting	Bahadurgarh, Haryana	Pro	Outdoor circuit
Off-Road Adventure Zone	Baliyawas, Gurgaon	Starter	Dirt karts + adventure
Mobo Kart	Janakpuri, Delhi	Starter	City-center indoor

Bangalore

Track	Location	Tier	Type
Meco Kartopia	Hennur-Bagalur Road	Enterprise	Grade 3 professional, 1.2km + 750m + 450m tracks
Aruani Grid	Sarjapur Road	Enterprise	1km professional asphalt + rally training
Velocity International Circuit	Bengaluru	Enterprise	International-standard circuit
Torq03	Marathahalli	Pro	500m floodlit, Sodi electric karts
Grips Go-Karting	Mysore Road, Anchepalya	Pro	Multi-level, 40+ karts across 6 levels
Red Riders Sports	Sarjapur	Pro	Adventure + outdoor karting
Raceway Motorsports	Kanakapura Road	Pro	350m outdoor circuit
Play Arena	Kasavanahalli	Starter	250m indoor, international-standard barriers
Wonderla	Jadenahalli, Mysore Road	Starter	Amusement park karting attraction
E-Zone Club	Chinnapanahalli, Marathahalli	Starter	Entertainment center

Mumbai

Track	Location	Tier	Type
Ajmera IndiKarting	Wadala	Enterprise	400m outdoor, precision timing system
Smaaash	Lower Parel	Enterprise	500m rooftop indoor — longest indoor in Mumbai
Rayo Racing Academy	Andheri	Enterprise	Professional racing academy + track
Republic of Karting	Navghar, NH48	Pro	24×7 outdoor — newest track in city
Hakone Entertainment	Powai	Pro	375m outdoor + arcade complex
Hakone	Panvel	Pro	Outdoor circuit
BOM Karting	Borivali East	Pro	Indoor, duo-kart feature, 2-min from metro
Ajanta Go Karting	Kurla West	Pro	Multiple engine capacity categories
Timezone	Inorbit Mall, Malad	Starter	225m indoor mall track
Snow World	Kurla West	Starter	200m indoor entertainment center

Pune

Track	Location	Tier	Type
Pune Kartdrome	Kharadi Bypass Road	Enterprise	650m championship circuit, 22ft wide, 5 acres
Formula Karting (The Mills)	Sangamvadi	Enterprise	Largest Sodi-approved championship circuit in India
IndiKarting	Near Eon IT Park, Kharadi	Pro	265m professional track, racing lessons available
IndiKarting	Seasons Mall, Magarpatta	Pro	Mall-based professional karting
Circuit 77	Lohegaon	Pro	500m outdoor, 13 technical bends
High Octane	Kondhwa	Pro	Pune's only fully indoor technical track
High Octane	Yerawada	Pro	Multi-location franchise, international-standard karts
Smaaash	Amanora Mall, Hadapsar	Pro	Indoor entertainment + karting
Raftaar Go Karting	Tathawade	Starter	Outdoor training track, affordable membership packages
Kartland	Abhiruchi Mall, Sinhgad Road	Starter	Mall-based, beginner-friendly

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