magnus919_agent-skills/yc-weekly-growth-compass/SKILL.md

name, description, license, compatibility, metadata

name	description	license	compatibility	metadata
yc-weekly-growth-compass	Make weekly startup growth decisions using growth rate, user behavior, and experiment evidence. Do not use this skill for runway, burn, or profitability trajectory analysis; use `yc-default-alive-calculator` for financial sustainability.	MIT	Python 3.9+ with standard library only (no external dependencies). The growth-compass.py script uses only math, json, and sys.	spec-version tags sources skills requires-toolsets 1.0 startup-growth, growth-rate, ycombinator, paul-graham, startup-metrics, weekly-growth, traction, compound-growth, startup-compass https://paulgraham.com/growth.html, https://paulgraham.com/ds.html, https://www.ycombinator.com/about yc-default-alive-calculator terminal

Weekly Growth Compass

"If there's one number every founder should always know, it's the company's growth rate. That's the measure of a startup. If you don't know that number, you don't even know if you're doing well or badly." — Paul Graham, "Startup = Growth" (September 2012)

This skill operationalizes Y Combinator's core growth philosophy into a repeatable weekly practice. The growth rate is not just a metric — it's a compass for every decision a founder makes.

When to Load

Trigger	Example
"What's my growth rate?"	Routine founder check-in
"Are we growing fast enough?"	Trajectory anxiety
"Should we prioritize feature X or growth Y?"	Decision framing
"Where will we be in a year?"	Projection/planning
"How does our growth compare to YC benchmarks?"	Benchmarking
"Is this initiative worth doing?"	Growth compass check
"How long to double our revenue?"	Milestone planning

How to Use

Quick Rule of Thumb (No Script)

YC's empirical benchmarks, based on measuring thousands of startups:

Weekly Growth	Annualized	YC Assessment
1%	1.7x	Concerning — haven't found product-market fit
2%	2.8x	Below average — need significant acceleration
5%	12.6x	Good — solid trajectory, keep pushing
7%	33.7x	Very good — exceptional progress
10%	142.0x	Outstanding — rare breakout trajectory

The inflection point: 5-7% weekly is the target zone YC coaches for.

Growth Compass Exercise (No Script)

Use this heuristic for any strategic decision:

1. State your target weekly growth rate (e.g., "7%")
2. For any proposed initiative, ask: "Does this serve our target growth rate?"
3. If yes → do it. If no → defer or drop it.
4. At end of week, measure actual growth. If you missed target, something else matters more than the thing you did.

This transforms the bewildering complexity of startup building into a single optimization problem, exactly as Graham intended.

Full Analysis (Script)

python scripts/growth-compass.py \
  --current-value 1200 \
  --previous-value 1000 \
  --period weekly

Or with a full series for trending:

python scripts/growth-compass.py \
  --series "1000,1050,1100,1200,1350,1420" \
  --period weekly

Required inputs

Flag	Description	Example
--current-value	Metric value this period	1200
--previous-value	Metric value last period	1000
Or --series	Comma-separated values over time	"1000,1050,1100"
--period	weekly, monthly, or quarterly	weekly

Optional inputs

Flag	Description	Example
--project-periods	Periods to project forward (default: 52)	104
--target-value	Target metric to reach	100000
--metric-name	Label for the metric (default: "users/revenue")	"MRR"
--json	Machine-readable JSON output
--dry-run	Validate inputs and show what would be computed without running

Output fields

Field	Meaning
growth_rate_pct	Calculated growth rate for the period
yc_assessment	Benchmark label (Concerning/Below Average/Good/Very Good/Outstanding)
projected_1yr	Value after 52 weeks at current rate
projected_2yr	Value after 104 weeks at current rate
doubling_time	Periods to double at current rate
time_to_target	If target set, periods to reach it
assessment	Plain-English interpretation

Methodology

Growth Rate Calculation

growth_rate = ((current_value - previous_value) / previous_value) × 100

For series with 3+ data points, the script computes:

• Period-over-period rates for each interval
• Mean growth rate (arithmetic average)
• Median growth rate (robust to outliers)
• Compound weekly growth rate (CWGR) — fitted from first to last value

The Compass Principle

From Graham's essay: "We usually advise startups to pick a growth rate they think they can hit, and then just try to hit it every week. If they decide to grow at 7% a week and they hit that number, they're successful for that week. There's nothing more they need to do. But if they don't hit it, they've failed in the only thing that mattered."

The script operationalizes this by:

1. Computing whether you hit your target
2. Projecting forward at current rate vs. target rate
3. Showing the gap in absolute terms so founders feel the urgency

Compound Growth Projection

future_value = current_value × (1 + growth_rate/100)^periods

The magic of compound growth at YC benchmarks:

Starting from $1,000/month MRR:

Weekly Growth	Month 12	Month 24	Month 36
1%	$1,700	$2,900	$4,900
5%	$12,600	$159,000	$2.0M
7%	$33,700	$1.1M	$38M
10%	$142,000	$20.2M	$2.9B

The difference between 5% and 7% weekly is the difference between a lifestyle business and a category-defining company. Small variations in growth rate produce qualitatively different outcomes.

The Decision Framework

For the Founder

1. Monday: Set this week's growth target
2. Every decision: "Does this serve the target?"
3. Friday: Measure actual growth
4. If hit: Successful week, nothing else matters
5. If missed: Alarmed. What went wrong? Adjust.

For the Investor/Advisor

Use YC's diagnostic frame:

What's your weekly growth rate?  ─→  < 5%: Founders aren't doing
    ↓                                    unscalable things
    ↓                                5-7%: Good, keep pushing
    ↓                                10%+: Exceptional
What's your growth rate trend?     ─→  Accelerating: product-market fit
    ↓                                    Decelerating: market saturation or churn
    ↓                                    Flat: plateau, needs intervention
Is revenue growing same as users?  ─→  No: monetization gap

Example: Early YC Company Assessment

python scripts/growth-compass.py \
  --current-value 35000 \
  --previous-value 32000 \
  --period monthly \
  --metric-name "MRR" \
  --target-value 100000

Growth rate: 9.4% monthly (~2.3% weekly) YC assessment: Below average weekly, solid monthly 1-year projection: ~$107K MRR Doubling time: ~7.7 months Months to $100K MRR: ~12 months

References

• references/growth-compass-framework.md — Full essay breakdown with quotes
• assets/compound-growth-table.md — Reference table for quick lookup
• yc-default-alive-calculator companion skill — For financial sustainability analysis

Available Scripts

Script	Purpose	Invocation
scripts/growth-compass.py	Deterministic CLI calculator: computes period growth rate, YC benchmark assessment, compound projections (1yr/2yr), doubling time, and time-to-target; accepts two values or a comma-separated series, with text or --json output. Run it whenever a founder asks for an actual growth number, projection, or benchmark rather than a rule-of-thumb answer.	python scripts/growth-compass.py --current-value 1200 --previous-value 1000 --period weekly --json

Prerequisites

• Python 3.9+ with the standard library only (per compatibility) — no external packages, API keys, or data files.
• Real metric inputs: current/previous values for one period, or at least a short series of historical values. The script computes arithmetic; it cannot invent your numbers.
• The terminal toolset (per frontmatter) to execute Python.

Limitations

• Growth rate is computed from exactly what you pass in: garbage inputs produce confident-looking output, so confirm the metric definition (users vs revenue vs MRR) and the period alignment before trusting results.
• Projections are pure compounding of the latest rate — they model no churn, seasonality, capacity limits, or deceleration.
• Series statistics need 3+ points; with only two values there is no mean/median/CWGR trend, just the single interval rate.
• The YC tier labels are benchmarks from Paul Graham's "Startup = Growth" essay, not a valuation or fundraising judgment.