Performance

Performance

Purview.ZodSharp is designed for maximum performance: validation rules are readonly record structs, hot paths use Span<T>, and the source generator emits direct typed codegen with no reflection. The committed BenchmarkDotNet suite measures every scenario.

Running the benchmarks

# All suites
dotnet run --project src/src/Benchmarks/Benchmarks.csproj -c Release
# or
just perf-tests

# A specific suite (the `--` passes the filter to BenchmarkDotNet)
dotnet run --project src/src/Benchmarks/Benchmarks.csproj -c Release -- --filter "*ObjectPerformanceTests*"

Results are written to BenchmarkDotNet.Artifacts/ (HTML, Markdown, logs) in the project directory. Use -c Release; the suite uses [MemoryDiagnoser] and a [SimpleJob] profile.

Measurement environment

• BenchmarkDotNet 0.15.8, .NET 10.0.12, Windows 11 (10.0.28020.2991).
• These figures are stale in one respect: the repository now pins BenchmarkDotNet 0.16.0-preview.2 (Directory.Packages.props), so the numbers below were produced by a different version than the suite currently builds against. They are also from one machine. Re-run the suite before relying on absolute values; use them for relative comparison between scenarios.
• 13th Gen Intel Core i9-13900KF 3.00 GHz (24 physical / 32 logical cores), X64 RyuJIT x86-64-v3.

Numbers are indicative; re-run on your own hardware for local planning.

Core validation (BasicPerformanceTests)

Scenario	Mean	Allocated
ValidateBoolean	2.170 ns	0 B
ValidateNumber	10.702 ns	0 B
ValidateString	41.627 ns	0 B
ValidateStringArray	57.031 ns	0 B
ValidateStringWithMultipleRules	77.313 ns	0 B
ValidateNumberWithMultipleRules	16.427 ns	0 B

Objects (ObjectPerformanceTests)

Scenario	Mean	Allocated
ValidateSimpleObject (2 fields)	89.78 ns	0 B
ValidateMediumObject (6 fields)	340.18 ns	0 B
ValidateComplexObject (13 fields, nested)	795.69 ns	0 B
ValidateComplexObjectInvalid	1,152.80 ns	1,960 B

Arrays (ArrayPerformanceTests)

Scenario	Mean	Allocated
ValidateSmallArray	124.4 ns	—
ValidateLargeArray (1000 items)	11,682.3 ns	—
ValidateMediumArray (100 items)	4,585.3 ns	—
ValidateNumberArray	12,797.3 ns	—
ValidateLargeArrayWithComplexSchema	8,011.8 ns	—
ValidateLargeArrayInvalid	11,206.7 ns	904 B

Heavy scenarios (HeavyPerformanceTests)

Scenario	Mean
ValidateDeepNestedObject (4 levels)	198.5 ns
ValidateWideObject (50 fields)	2,217.2 ns
ValidateNestedArray	177.7 ns
ValidateStringWithManyRefinements	114.7 ns
ValidateLargeObjectWithArrays	19,578.0 ns

Transforms (TransformPerformanceTests)

Scenario	Mean	Allocated
TransformToLower	22.26 ns	48 B
TransformToUpper	28.39 ns	48 B
TransformTrim	29.10 ns	48 B
TransformChained	40.71 ns	96 B
TransformWithValidation	78.79 ns	112 B

Unions (UnionPerformanceTests)

Scenario	Mean	Allocated
ValidateUnion_String (first option)	48.70 ns	0 B
ValidateUnion_Number (second option)	69.38 ns	592 B
ValidateUnion_Boolean (third option)	99.71 ns	792 B
ValidateDiscriminatedUnion_FirstOption	169.33 ns	0 B
ValidateDiscriminatedUnion_SecondOption	171.90 ns	0 B
ValidateUnion_Invalid	195.87 ns	1,360 B

Note

Union validations allocate on the failure path and while attempting non-matching options — the string option is free, but matching a later option allocates the error collection from the earlier attempts. Discriminated unions dispatch directly and remain zero-allocation.

Memory (MemoryPerformanceTests)

All valid-input paths for the core schema types are zero-allocation:

Scenario	Mean	Ratio
ValidateString_Allocations (baseline)	45.82 ns	1.00
ValidateObject_Allocations	94.28 ns	2.06
ValidateArray_Allocations	1,180.24 ns	25.82

Note

The string transforms, ZodString.ValidateSpan (its result carries a string), and non-first union options are the allocation exceptions. Use ZodString.IsValidSpan for an allocation-free span check. See Guarantees and Limitations.

UUID validation (UuidPerformanceTests)

UUID validation uses a zero-allocation char-scan (version nibble at position 14, variant nibble at position 19) instead of a regex. Measured against the previous compiled regex:

Scenario	Mean	Allocated
Rule_CharScan_Valid (.UUID())	21.99 ns	0 B
Rule_LegacyRegex_Valid (previous implementation)	27.50 ns	0 B
Rule_CharScan_Invalid	< 1 ns	0 B
Rule_LegacyRegex_Invalid	14.22 ns	0 B
Rule_CharScan_Nil	20.67 ns	0 B
Rule_CharScanV7_Valid (.UUID(UuidVersion.V7))	20.89 ns	0 B
Rule_CharScanV7_Mismatch	20.11 ns	0 B
Schema_UUID_Valid	29.80 ns	0 B
Schema_UUIDV7_Valid	26.64 ns	0 B

The char-scan is ~20% faster than the previous regex on the valid path, is version-aware at no extra cost, and rejects wrong-length strings in under a nanosecond.

Optimizations that make it fast

1. Struct-based rules — every rule is a readonly record struct implementing IValidationRule<T>, so there is no per-validation object allocation.
2. Span-aware helpers — Span<T>/ReadOnlySpan<T> APIs and ArrayPool<T>-backed helpers. The shipped string rules implement IStringValidationRule (except the URL and Base64 rules, which need a string), so ZodString.ValidateSpan validates the span directly and only materialises the value string for its result; ZodString.IsValidSpan avoids that allocation entirely.
3. Compiled validators — CompiledValidator.Compile removes interface dispatch (see Compiled Validators and Caching).
4. Source generation — [ZodSchema] emits direct property access and typed equality checks with no reflection (see Source Generator).
5. Cacheable schema instances — a fully built schema is safe to cache and share, so SchemaCache avoids repeated construction (see Compiled Validators and Caching). Building is not immutable: the fluent rule methods mutate the receiver. See Custom Rules for extending rules.

The allocations on a successful validation are limited to the string transforms (ToLower/ToUpper/Trim), ZodString.ValidateSpan (its result carries a string), and the union non-first-option paths.