Make API reference header state reliable

[SandroMaglione]

Summary

• show the active theme mode (System, Light, or Dark) in the header control
• fetch the repository star count during the GitHub Pages build
• render the count directly into static HTML and remove the browser-side GitHub API request
• validate the build input and document the Pages workflow contract

The previous theme label described the next action, which made light and dark appear inverted. The star badge depended on a cross-origin browser request that content blockers could suppress, leaving the badge hidden without an error.

Changeset

• Added or updated for a library or package-metadata change
• Not required because this PR does not change src/ or package.json

Validation

• pnpm check
• Relevant example checks, when examples changed
• Reviewed the automated type-performance report, when the public TypeScript API or inference changed
• Reviewed the automated runtime-performance report, when runtime behavior changed

[github-actions]

Type performance

Measured with TypeScript 6.0.3 and skipLibCheck=true.

Scenario	Base	PR	Difference
Effect only	55	55	0 (0.0%)
Import effect-machine	55	55	0 (0.0%)
Machine.defineStates (3 states)	2,965	2,965	0 (0.0%)
Machine.make (3 states, 2 events)	8,715	8,715	0 (0.0%)
machine.handle (3 states, 2 transitions)	23,492	23,492	0 (0.0%)
machine.handle (depth 8)	117,075	117,075	0 (0.0%)
machine.handle (depth 12)	129,713	129,713	0 (0.0%)
machine.handle (depth 16)	145,055	145,055	0 (0.0%)
machine.handle (depth 24)	183,851	183,851	0 (0.0%)
machine.handle (wide depth 16)	214,189	214,189	0 (0.0%)
machine.handle (parallel/history/choice)	132,667	132,667	0 (0.0%)
machine.handle (4 successive calls)	128,674	128,674	0 (0.0%)
machine exact input/output/error/services	110,584	110,584	0 (0.0%)
execution adapter readiness	127,854	127,854	0 (0.0%)

Marginal instantiations are measured against the matching setup without that API call:

Scenario	Base	PR	Difference
Import effect-machine	0	0	0
Machine.defineStates (3 states)	2,910	2,910	0 (0.0%)
Machine.make (3 states, 2 events)	5,742	5,742	0 (0.0%)
machine.handle (3 states, 2 transitions)	14,777	14,777	0 (0.0%)
machine.handle (depth 8)	109,601	109,601	0 (0.0%)
machine.handle (depth 12)	121,039	121,039	0 (0.0%)
machine.handle (depth 16)	135,181	135,181	0 (0.0%)
machine.handle (depth 24)	171,577	171,577	0 (0.0%)
machine.handle (wide depth 16)	202,224	202,224	0 (0.0%)
machine.handle (parallel/history/choice)	114,331	114,331	0 (0.0%)
machine.handle (4 successive calls)	113,703	113,703	0 (0.0%)
machine exact input/output/error/services	100,670	100,670	0 (0.0%)
execution adapter readiness	102,092	102,092	0 (0.0%)

Check times (informational)

Scenario	Base	PR
Effect only	0.03s	0.03s
Import effect-machine	0.03s	0.03s
Machine.defineStates (3 states)	0.09s	0.09s
Machine.make (3 states, 2 events)	0.15s	0.15s
machine.handle (3 states, 2 transitions)	0.21s	0.22s
machine.handle (depth 8)	0.47s	0.47s
machine.handle (depth 12)	0.52s	0.51s
machine.handle (depth 16)	0.57s	0.56s
machine.handle (depth 24)	0.65s	0.64s
machine.handle (wide depth 16)	0.67s	0.69s
machine.handle (parallel/history/choice)	0.58s	0.56s
machine.handle (4 successive calls)	0.55s	0.55s
machine exact input/output/error/services	0.47s	0.48s
execution adapter readiness	0.52s	0.53s

Type instantiations are the comparison metric. Check time varies with runner load and is informational only.

[github-actions]

Runtime performance

Median of 5 independent benchmark processes on AMD EPYC 9V74 80-Core Processor with Node v24.18.0.

Pull request baseline

Scenario	Effect Machine	XState 5	XState 6 alpha
Plan counter transitions	161,981 transitions/s	172,365 transitions/s	16,289 transitions/s
Drain burst with terminal fence	645,758 increments/s	485,187 increments/s	218,236 increments/s
Drain burst with a change observer	598,820 increments/s	479,162 increments/s	216,479 increments/s
Lookup and send to one child	532,020 increments/s	477,909 increments/s	213,163 increments/s
Start and stop a machine	211,104 machines/s	226,963 machines/s	169,233 machines/s
Start and stop a parent with one child	58,357 families/s	91,853 families/s	56,990 families/s
Plan transitions through a compound state	145,949 transitions/s	—	—
Plan transitions through parallel regions	115,051 transitions/s	—	—
Drain burst through a compound state	614,035 events/s	425,718 events/s	213,077 events/s
Drain burst through two parallel regions	567,831 events/s	325,108 events/s	171,688 events/s
Drain a compound-state burst with a change observer	568,620 events/s	—	—

Effect runtime reference points

Scenario	Effect Machine	Effect runtime primitives
Start and stop a raw generic process	35,623 processes/s	—
Start and stop a raw compiled process	89,310 processes/s	—
Start and interrupt a suspended fiber	—	203,335 fibers/s
Start and stop a queue worker	—	147,037 workers/s
Start and stop an actor shell	—	135,483 actors/s
Start and stop two actor shells	—	84,767 families/s
Update an owner-only mutable snapshot	—	400,962,311 updates/s
Update a synchronized snapshot	—	2,132,219 updates/s
Create, resolve, and await a terminal latch	—	2,135,684 latches/s

Memory profile	Effect Machine	XState 5	XState 6 alpha	Effect runtime primitives
Idle machine	1.5 KiB	3.8 KiB	2.2 KiB	—
Raw generic managed process	12.7 KiB	—	—	—
Raw compiled process	2.8 KiB	—	—	—
Two independent idle machines	3.0 KiB	7.3 KiB	3.9 KiB	—
Idle parent with one child	4.8 KiB	5.5 KiB	4.0 KiB	—
Parent with observed child registry	9.0 KiB	—	—	—
Parent with observed invoked child snapshots	5.0 KiB	—	—	—
Suspended Effect fiber	—	—	—	0.6 KiB
Effect queue with waiting fiber	—	—	—	2.8 KiB
Effect mailbox actor shell	—	—	—	3.2 KiB
Two Effect actor shells	—	—	—	6.8 KiB

Effect Machine change from base

Metric	Base	Base variability	PR	PR variability	Difference
Plan counter transitions	159,857 transitions/s	0.9% MAD	161,981 transitions/s	1.0% MAD	+1.3%
Drain burst with terminal fence	632,889 increments/s	2.5% MAD	645,758 increments/s	5.6% MAD	+2.0%
Drain burst with a change observer	581,738 increments/s	1.8% MAD	598,820 increments/s	1.8% MAD	+2.9%
Lookup and send to one child	536,308 increments/s	1.0% MAD	532,020 increments/s	3.0% MAD	-0.8%
Start and stop a machine	210,172 machines/s	0.4% MAD	211,104 machines/s	1.5% MAD	+0.4%
Start and stop a parent with one child	60,372 families/s	0.8% MAD	58,357 families/s	2.5% MAD	-3.3%
Plan transitions through a compound state	146,596 transitions/s	0.4% MAD	145,949 transitions/s	0.5% MAD	-0.4%
Plan transitions through parallel regions	114,815 transitions/s	0.9% MAD	115,051 transitions/s	1.0% MAD	+0.2%
Drain burst through a compound state	622,022 events/s	1.7% MAD	614,035 events/s	1.2% MAD	-1.3%
Drain burst through two parallel regions	567,265 events/s	1.0% MAD	567,831 events/s	0.7% MAD	+0.1%
Drain a compound-state burst with a change observer	575,250 events/s	0.6% MAD	568,620 events/s	0.8% MAD	-1.2%
Idle machine heap per unit	1.5 KiB	0.0% MAD	1.5 KiB	0.0% MAD	-0.0%
Raw generic managed process heap per unit	12.7 KiB	0.1% MAD	12.7 KiB	0.0% MAD	-0.0%
Raw compiled process heap per unit	2.8 KiB	0.7% MAD	2.8 KiB	0.4% MAD	+0.5%
Two independent idle machines heap per unit	2.9 KiB	0.0% MAD	3.0 KiB	0.0% MAD	+0.2%
Idle parent with one child heap per unit	4.8 KiB	0.0% MAD	4.8 KiB	0.0% MAD	0.0%
Parent with observed child registry heap per unit	9.0 KiB	0.0% MAD	9.0 KiB	0.0% MAD	-0.0%
Parent with observed invoked child snapshots heap per unit	5.0 KiB	0.0% MAD	5.0 KiB	0.0% MAD	+0.2%

Effect runtime reference change from base

Metric	Base	Base variability	PR	PR variability	Difference
Start and stop a raw generic process	35,307 processes/s	1.8% MAD	35,623 processes/s	2.5% MAD	+0.9%
Start and stop a raw compiled process	90,114 processes/s	0.3% MAD	89,310 processes/s	0.5% MAD	-0.9%
Start and interrupt a suspended fiber	202,143 fibers/s	0.4% MAD	203,335 fibers/s	0.2% MAD	+0.6%
Start and stop a queue worker	148,810 workers/s	0.3% MAD	147,037 workers/s	1.2% MAD	-1.2%
Start and stop an actor shell	136,407 actors/s	0.3% MAD	135,483 actors/s	1.0% MAD	-0.7%
Start and stop two actor shells	85,925 families/s	1.1% MAD	84,767 families/s	1.6% MAD	-1.3%
Update an owner-only mutable snapshot	400,962,309 updates/s	0.0% MAD	400,962,311 updates/s	0.0% MAD	+0.0%
Update a synchronized snapshot	2,130,034 updates/s	1.3% MAD	2,132,219 updates/s	3.4% MAD	+0.1%
Create, resolve, and await a terminal latch	2,129,671 latches/s	1.7% MAD	2,135,684 latches/s	0.9% MAD	+0.3%

Versions and interpretation

• Effect Machine: 0.5.1
• XState 5: 5.32.5
• XState 6 alpha: 6.0.0-alpha.31
• Effect runtime primitives: 4.0.0-beta.107

Higher throughput is better; lower heap is better. Variability is the median absolute deviation across independent processes, relative to their median. Runtime measurements on shared GitHub-hosted hardware remain informational, so small differences should be confirmed across multiple workflow runs.