Zero-Reflection Hot Path

Grove uses Go reflection exactly once — at model registration time. The hot path (query building, execution, and result scanning) uses cached field offsets and pooled buffers, targeting 5% or less overhead versus raw database driver usage.

Reflect-Once Architecture01

Registration Phase (Startup)

When you call db.RegisterModel(), Grove inspects the struct using reflection and caches:

Field names, types, and offsets
Tag metadata (column name, constraints, relations, privacy)
Type converters (Go type to DB type and back)
Scan functions (pre-compiled for each field)

// Reflection happens here — once per model type
db.RegisterModel((*User)(nil))
db.RegisterModel((*Post)(nil))
db.RegisterModel((*Comment)(nil))

Hot Path (Every Query)

After registration, every query operation uses cached metadata:

// Zero reflection — uses cached field offsets and pooled buffers
var users []User
err := db.NewSelect(&users).
    Where("active = $1", true).
    Scan(ctx)

The query builder:

Looks up the User table metadata from the registry (map lookup)
Builds SQL using cached column names (string concatenation with pooled buffers)
Scans results using cached field offsets (unsafe pointer arithmetic, no reflection)

Pooled Buffers02

Grove pools byte buffers to minimize allocations during query building:

Query strings are built into sync.Pool-managed buffers
Argument slices are pooled and reused
Result scanning reuses column-to-field mappings

Target: 0-2 heap allocations per simple query.

Performance Targets03

Grove targets less than 5% overhead versus raw database driver usage. Formal benchmarks will be published after the performance optimization phase.

Run benchmarks yourself:

go test -bench=. -benchmem ./pgdriver/

Why Not Code Generation?04

Code generation (like sqlc or ent) avoids reflection entirely but comes with trade-offs:

Requires a build step
Generated code is harder to debug
Doesn't support dynamic model composition (Forge extensions adding fields at runtime)

Grove's reflect-once approach provides near-codegen performance while maintaining the flexibility of a runtime ORM.

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Native Query Syntax

Type-Safe IDs