AI Slop Code Risk Monitor

fastify/fastify

Name: fastify/fastify — JavaScript Code Quality & Security Review | AI Slop Code Risk Monitor
Creator: AI Slop Code Risk Monitor

Adjusted legacy signal; badge bands: 25 / 50 / 75 (different from dashboard bands).

Fast and low overhead web framework, for Node.js

0.5 Low pattern signal View on GitHub

Open-Source Code Quality, Security and Technical Debt Review

This report summarizes scanner evidence for fastify/fastify, a JavaScript project with 37,332 GitHub stars. SynthScan examined 101,327 lines of code across 375 source files, recording 41 pattern matches distributed across 5 syntactic categories. The legacy adjusted pattern signal is 0.5 (Low pattern signal); it is not an authorship estimate.

Use the findings to ask whether maintainers can explain intent, verify dependencies, simplify unnecessary scaffolding, and focus review effort. Risk Payload v1 adds ownership, supply-chain, over-engineering, and review-effort vectors when available. These are prompts for human verification, not probabilities, security findings, or measured maintenance costs.

0.5

Adjusted Signal

0.5

Raw Pattern Score

100%

Time Factor

2026-10-29

Last Push

37.3K

Stars

JavaScript

Language

101.3K

Lines of Code

375

Files

Pattern Hits

2026-10-31

Scan Date

0.00

HC Hit Rate

Risk Review · Payload v1

Use each vector to guide manual verification of the underlying findings.

Payload schema: 1.0.0 · Engine: 2.0.0 · Scoring: heuristic-density-v1 · Scan date: 2026-10-31.

Cognitive Ownership Risk 2.0/100 · LOW

Can maintainers explain intent, assumptions, and trade-offs? 33 finding(s).

Hallucinated Dependency & Supply Chain Risk 0.5/100 · LOW

Are imports declared and package/API names verified? 8 finding(s).

Agent Over-Engineering Ratio 1.3/100 · LOW

Are wrappers, guards, and repeated structures necessary? 24 finding(s).

PR Review Velocity Impact 2.2/100 · LOW

Which changes need focused human review? 41 finding(s).

What These Metrics Mean

Adjusted Signal: Legacy pattern score normalized per 1,000 scanned lines and multiplied by the repository-level time factor. It is not an estimate of AI authorship.
Raw Pattern Score: Sum of severity- and context-weighted pattern findings before applying the time factor.
Time Factor: A coarse multiplier based on repository last-push metadata. It does not identify when individual code was written.
Pattern Hits: Count of configured pattern findings. Review each location and surrounding code before acting.
HC Hit Rate: High- and critical-severity findings per scanned file. Severity is a configured detector weight, not proof of a vulnerability or authorship.
Lines / Files: Scan coverage denominators used by the legacy normalized score.

Pattern-Signal History

This chart tracks the legacy adjusted pattern score across scan runs. Changes can reflect source changes, scan coverage, or detector/scoring versions; they do not measure AI adoption or prove that a team refactored code. Compare runs only when their scoring versions are compatible. The dashed line tracks the raw pattern-hit count.

Severity Breakdown

Groups findings by configured severity weight. Severity is not a confidence estimate, security rating, or proof that a package is missing. Verify imports against the project's manifests and inspect each finding in its local design context.

CRITICAL 0HIGH 1MEDIUM 0LOW 40

Directory Score Breakdown

This horizontal bar chart shows where configured pattern scores accumulate across directories. Treat the bars as locations to inspect, not as evidence of authorship or code quality. Use the file-level findings to decide whether a directory needs a focused ownership, dependency, complexity, or review check.

Pattern Findings

The scanner identified 41 distinct pattern matches across 5 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a detector match to inspect in context. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.

Reading the findings table: The Severity column indicates the configured finding weight (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — legacy comment-context matches receive a ×1.5 score weight. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier under the legacy scoring model.

Hyper-Verbose Identifiers24 hits · 26 pts

Severity	File	Line	Snippet	Context
LOW	fastify.js	728	function buildAsyncConstraintCallback (isAsync, req, res) {	CODE
LOW	fastify.js	980	function defaultClientErrorHandler (err, socket) {	CODE
LOW	fastify.js	1020	function validateSchemaErrorFormatter (schemaErrorFormatter) {	CODE
LOW	test/skip-reply-send.test.js	115	function testHandlerOrBeforeHandlerHook (test, hookOrHandler) {	CODE
LOW	test/decorator.test.js	1259	function assertsThrowOnUndeclaredDecorator (notDecorated, instanceType) {	CODE
LOW⚡	test/types/instance.tst.ts	128	function notFoundpreHandlerHandler (	CODE
LOW⚡	test/types/instance.tst.ts	133	async function notFoundpreHandlerAsyncHandler (	CODE
LOW⚡	test/types/instance.tst.ts	137	function notFoundpreValidationHandler (	CODE
LOW⚡	test/types/instance.tst.ts	142	async function notFoundpreValidationAsyncHandler (	CODE
LOW	test/types/instance.tst.ts	207	function serializerWithInvalidReturn (payload: unknown, statusCode: number) { }	CODE
LOW	test/types/instance.tst.ts	211	function invalidSchemaErrorFormatter (err: Error) {	CODE
LOW	test/scripts/validate-ecosystem-links.test.js	8	function loadValidateEcosystemLinksModule () {	CODE
LOW	docs/Reference/Server.md	775	function defaultClientErrorHandler (err, socket) {	CODE
LOW	lib/route.js	596	function handleOnRequestAbortHooksErrors (reply, err) {	CODE
LOW	lib/route.js	612	function normalizeAndValidateMethod (method) {	CODE
LOW	lib/route.js	638	function validateHandlerTimeoutOption (handlerTimeout) {	CODE
LOW	lib/content-type-parser.js	417	function removeAllContentTypeParsers () {	CODE
LOW	lib/request.js	99	function getLastEntryInMultiHeaderValue (headerValue) {	CODE
LOW	lib/request.js	105	function buildRequestWithTrustProxy (R, trustProxy) {	CODE
LOW	lib/server.js	22	function defaultResolveServerListeningText (address) {	CODE
LOW	lib/logger-factory.js	51	function defaultChildLoggerFactory (logger, bindings, opts) {	CODE
LOW	lib/validation.js	18	function compileSchemasForSerialization (context, compile) {	CODE
LOW	lib/validation.js	273	function compileSchemasForValidation (context, compile, isCustom) {	CODE
LOW	lib/context.js	85	function defaultSchemaErrorFormatter (errors, dataVar) {	CODE

Fake / Example Data8 hits · 11 pts

Severity	File	Line	Snippet	Context
LOW	test/schema-serialization.test.js	415	fullName: 'John Doe',	CODE
LOW⚡	test/internals/reply.test.js	709	sample: '{"_links":{"self":{"href":"https://api.fastify.test/people/1"}},"name":"John Doe"}'	CODE
LOW⚡	test/internals/reply.test.js	717	sample: '{"@context":"https://json-ld.org/contexts/person.jsonld","name":"John Doe"}'	CODE
LOW⚡	test/internals/reply.test.js	725	sample: '{"class":"person","properties":{"name":"John Doe"}}'	CODE
LOW⚡	test/internals/reply.test.js	794	sample: JSON.parse('{"_links":{"self":{"href":"https://api.fastify.test/people/1"}},"name":"John Doe"}')	CODE
LOW⚡	test/internals/reply.test.js	802	sample: JSON.parse('{"@context":"https://json-ld.org/contexts/person.jsonld","name":"John Doe"}')	CODE
LOW⚡	test/internals/reply.test.js	806	sample: JSON.parse('{"class":"person","properties":{"name":"John Doe"}}')	CODE
LOW	docs/Reference/Hooks.md	861	name: 'Jane Doe',	CODE

AI Response Leakage1 hit · 8 pts

Severity	File	Line	Snippet	Context
HIGH	docs/Guides/Recommendations.md	140	# In this example we are defaulting unmatched domain requests to a single	COMMENT

Over-Commented Block7 hits · 7 pts

Severity	File	Line	Snippet	Context
LOW	docs/Guides/Recommendations.md	101	use_backend default-server	COMMENT
LOW	docs/Guides/Recommendations.md	121	# Here we define rule pairs to direct requests to appropriate Node.js	COMMENT
LOW	docs/Guides/Recommendations.md	181	server 10.10.11.2:80;	COMMENT
LOW	docs/Reference/Server.md	2201	fastify.get('/test/hello', () => {})	COMMENT
LOW	docs/Reference/Server.md	2221	// • (onRequest) ["anonymous()"]	COMMENT
LOW	lib/schema-controller.js	81	// legacy behavior	COMMENT
LOW	lib/validation.js	61	// their canonical or mixed case — `properties`, `required`, and the Draft 7	COMMENT

Overly Generic Function Names1 hit · 1 pts

Severity	File	Line	Snippet	Context
LOW	lib/handle-request.js	24	function handleRequest (err, request, reply) {	CODE