ORG X-RAY · PLATE № 001 SUBJECT: POSTHOG/POSTHOG · WINDOW: 120 DAYS · 2026-07-04

PostHog pays 90th-percentile because they believe in the 10x engineer. Their own git history says the ratio is 10.4x.

One evening, one public repository, no interviews, no dashboards. This is what an engineering org looks like on film — read from nothing but its commit history.

PostHog's handbook states the company pays engineers near the top of market “because we believe there is a 10x difference between average and top engineers.” Almost every company believes some version of this. Almost none can measure it, and none of them publish the evidence.

PostHog accidentally does. Their product is open source, so their engineering org's complete work record sits in public. I pointed the instrument at it: 13,548 commits, 205 human contributors, 120 days. Five findings.

FINDING 1 The 10x claim survives measurement, almost exactly

Define the core roster as everyone with ≥20 commits in the window: 92 people producing 96% of all output. The median core engineer shipped 94 commits. The top contributor shipped 975: a 10.4x spread, in an org whose comp philosophy is built on the number 10.

Top of the core roster, anonymized as a courtesy; the underlying data is public. Line counts include generated code and are directional only.
EngineerCommits / 120dActive daysVolume
Engineer A97558██████████████████████████████
Engineer B641105████████████████████
Engineer C41791█████████████
Engineer D40686████████████
Engineer E34175██████████
Engineer F25971████████
Engineer G21555██████
Engineer H21463██████
…84 more ≥20 commitsmedian 94███

Engineer B is its own finding: 105 active days out of a possible ~120, meaning commits on 87% of all days in the window, weekends included. Volume gets celebrated; that kind of metronomic consistency is rarer and harder to hire for.

FINDING 2 Depth, not hero-dependence

The top five contributors hold just 24% of output; the top twenty hold 48%. Half of everything shipped comes from outside the top twenty. That is a deep bench: the org would absorb the loss of any single engineer, including the 10.4x one.

What the sick version looks like: in typical mid-market teams this instrument examines, two or three people per team carry 60–80% of meaningful output, usually at or below median pay, and the org has no idea. That's not a velocity problem; it's an unpriced bus-factor liability.

FINDING 3 The median is the real headline

Forget the star. PostHog's median core engineer ships 94 commits per 120 days: roughly one merged change per working day, sustained for four months. In most mid-market companies, that figure would make you the top performer on your team, possibly in the org. Here it makes you exactly average.

This is what "we pay 90th percentile" buys when it works: not one hero, but a median that would be a standout anywhere else.

FINDING 4 Churn discipline: 0.3%

Of 13,548 commits, just 44 are reverts, or 0.3%. Shipping this fast with this little walk-back means the safety rails (review, CI, flags) are real, not ceremonial.

What the sick version looks like: individual engineers whose commits self-cancel at double-digit rates (ship, break, revert, re-ship), sometimes running for years in critical paths, invisible because nobody measures churn per person. The instrument finds these in minutes.

FINDING 5 Velocity is accelerating, and the unit economics are public

Mar → Jun commits/mo2,384 → 4,310
Core roster92 engineers
Est. eng payroll~$23M/yr
Cost per shipped change~$675

Monthly output rose from 2,384 human commits in March to 4,310 in June; the best month in the window is the most recent one. Because PostHog also publishes its compensation philosophy (90th percentile; public market data puts their median US engineer around $255K), you can price the machine from the outside: roughly $23M in annual engineering payroll producing ~34,000 changes a year, about $675 per shipped change. Most CFOs cannot produce that number for their own company. It took one evening to produce it for someone else's.

FINDING 6 Review is human, and it takes an hour

Median open → merge~1 hour
Merged < 4h65%
Human-approved95%
Median PR size4 files / 94 lines

The obvious suspicion about agent-era velocity is that review died. The GitHub API says otherwise: of the last 100 merged PRs, 95 carry an approving review, 9 are bot-authored, and the median PR goes from opened to merged in about one hour. The p90 is 14 hours, so even the slow tail clears in a day.

The mechanism is a flywheel, not heroics: the median PR is 4 files and 94 lines, which reviews in minutes, so nobody defers it, so merges are cheap, so people ship small, and the loop closes. Review latency may be the single best one-number gauge of an engineering org: trivial to measure, impossible to fake without actually fixing the system, and it predicts everything else on this plate.

What the sick version looks like: PRs that lag for days, review load concentrated on the same two or three carriers who already write the load-bearing code, and engineers rationally batching work into big risky PRs because every review round-trip costs a week. The queue, not the coding, caps the org's throughput.

METHOD & honest limits

Source: the public posthog/posthog repository, last 120 days, bots and automation excluded, merge commits excluded. Core roster = ≥20 commits. Roster anonymized as a courtesy, not for secrecy; the data is public, so every number above can be checked.

Limits, stated plainly: commit counts are not value. Line counts are inflated by generated code. A public monorepo shows most, not all, of an org's work (some contributors here are community, mitigated by the core cutoff). Cross-org comparisons must normalize for PR grain (one chunky PR elsewhere ≈ two or three PostHog-sized ones; both conventions squash-merge, so within-org ratios hold) and for stakeholder surface: a product whose customers are engineers pays its communication tax in writing, which compounds as docs and specs; orgs serving non-technical stakeholders pay it in meetings, which vanish. A fair examination prices that discount first and reports what survives it. And a healthy surface doesn't rule out deeper issues; this is the instrument's quick pass. The full examination reads work-type (who does load-bearing systems work vs. contained UI), per-person churn loops, fade patterns, manager-absorption signatures, and bus-factor concentration: the things that only show up when you read the history, not count it.

Why PostHog: they published the claim and the evidence. The verdict happens to be flattering; this is what a healthy org looks like on film. The instrument exists because most orgs are not this one.