Why Go
- Case Studies
  
  Common problems companies solve with Go
- Use Cases
  
  Stories about how and why companies use Go
- Security
  
  How Go can help keep you secure by default
Learn
Docs
- Effective Go
  
  Tips for writing clear, performant, and idiomatic Go code
- Go User Manual
  
  A complete introduction to building software with Go
- Standard library
  
  Reference documentation for Go's standard library
- Release Notes
  
  Learn what's new in each Go release
Packages
Community
- Recorded Talks
  
  Videos from prior events
- Meetups
  
  Meet other local Go developers
- Conferences
  
  Learn and network with Go developers from around the world
- Go blog
  
  The Go project's official blog.
- Go project
  
  Get help and stay informed from Go
- Get connected

wasmtime

package module

Go to main page

Versions in this module

v43

v43.0.2

Apr 7, 2026

v43.0.1

Apr 3, 2026

v43.0.0

Apr 1, 2026

Changes in this version

+ const DIR_READ

+ const DIR_WRITE

+ const FILE_READ

+ const FILE_WRITE

+ func ModuleValidate(engine *Engine, wasm []byte) error

+ func Wat2Wasm(wat string) ([]byte, error)

+ type AsExtern interface

+ AsExtern func() C.wasmtime_extern_t

+ type AsExternType interface

+ AsExternType func() *ExternType

+ type Caller struct

+ func (c *Caller) Context() *C.wasmtime_context_t

+ func (c *Caller) Data() interface{}

+ func (c *Caller) GetExport(name string) *Extern

+ type Config struct

+ func NewConfig() *Config

+ func (cfg *Config) CacheConfigLoad(path string) error

+ func (cfg *Config) CacheConfigLoadDefault() error

+ func (cfg *Config) Close()

+ func (cfg *Config) EnableCraneliftFlag(flag string)

+ func (cfg *Config) SetConsumeFuel(enabled bool)

+ func (cfg *Config) SetCraneliftDebugVerifier(enabled bool)

+ func (cfg *Config) SetCraneliftFlag(name string, value string)

+ func (cfg *Config) SetCraneliftNanCanonicalization(enabled bool)

+ func (cfg *Config) SetCraneliftOptLevel(level OptLevel)

+ func (cfg *Config) SetDebugInfo(enabled bool)

+ func (cfg *Config) SetEpochInterruption(enable bool)

+ func (cfg *Config) SetGCSupport(enabled bool)

+ func (cfg *Config) SetMacOSUseMachPorts(enabled bool)

+ func (cfg *Config) SetMaxWasmStack(size int)

+ func (cfg *Config) SetMemoryInitCOWSet(enabled bool)

+ func (cfg *Config) SetNativeUnwindInfo(enabled bool)

+ func (cfg *Config) SetParallelCompilation(enabled bool)

+ func (cfg *Config) SetProfiler(profiler ProfilingStrategy)

+ func (cfg *Config) SetStrategy(strat Strategy)

+ func (cfg *Config) SetTarget(target string) error

+ func (cfg *Config) SetWasmBulkMemory(enabled bool)

+ func (cfg *Config) SetWasmComponentModel(enabled bool)

+ func (cfg *Config) SetWasmFunctionReferences(enabled bool)

+ func (cfg *Config) SetWasmGC(enabled bool)

+ func (cfg *Config) SetWasmMemory64(enabled bool)

+ func (cfg *Config) SetWasmMultiMemory(enabled bool)

+ func (cfg *Config) SetWasmMultiValue(enabled bool)

+ func (cfg *Config) SetWasmReferenceTypes(enabled bool)

+ func (cfg *Config) SetWasmRelaxedSIMD(enabled bool)

+ func (cfg *Config) SetWasmRelaxedSIMDDeterministic(enabled bool)

+ func (cfg *Config) SetWasmSIMD(enabled bool)

+ func (cfg *Config) SetWasmTailCall(enabled bool)

+ func (cfg *Config) SetWasmThreads(enabled bool)

+ func (cfg *Config) SetWasmWideArithmetic(enabled bool)

+ type Engine struct

+ func NewEngine() *Engine

+ func NewEngineWithConfig(config *Config) *Engine

+ func (engine *Engine) Close()

+ func (engine *Engine) IncrementEpoch()

+ func (engine *Engine) IsPulley() bool

+ type Error struct

+ func (e *Error) Close()

+ func (e *Error) Error() string

+ func (e *Error) ExitStatus() (int32, bool)

+ type ExportType struct

+ func NewExportType(name string, ty AsExternType) *ExportType

+ func (ty *ExportType) Close()

+ func (ty *ExportType) Name() string

+ func (ty *ExportType) Type() *ExternType

+ type Extern struct

+ func (e *Extern) AsExtern() C.wasmtime_extern_t

+ func (e *Extern) Close()

+ func (e *Extern) Func() *Func

+ func (e *Extern) Global() *Global

+ func (e *Extern) Memory() *Memory

+ func (e *Extern) Table() *Table

+ func (e *Extern) Type(store Storelike) *ExternType

+ type ExternType struct

+ func (ty *ExternType) AsExternType() *ExternType

+ func (ty *ExternType) Close()

+ func (ty *ExternType) FuncType() *FuncType

+ func (ty *ExternType) GlobalType() *GlobalType

+ func (ty *ExternType) MemoryType() *MemoryType

+ func (ty *ExternType) TableType() *TableType

+ type Frame struct

+ func (f *Frame) FuncIndex() uint32

+ func (f *Frame) FuncName() *string

+ func (f *Frame) FuncOffset() uint

+ func (f *Frame) ModuleName() *string

+ func (f *Frame) ModuleOffset() uint

+ type Func struct

+ func NewFunc(store Storelike, ty *FuncType, f func(*Caller, []Val) ([]Val, *Trap)) *Func

+ func WrapFunc(store Storelike, f interface{}) *Func

+ func (f *Func) AsExtern() C.wasmtime_extern_t

+ func (f *Func) Call(store Storelike, args ...interface{}) (interface{}, error)

+ func (f *Func) Type(store Storelike) *FuncType

+ type FuncType struct

+ func NewFuncType(params, results []*ValType) *FuncType

+ func (ty *FuncType) AsExternType() *ExternType

+ func (ty *FuncType) Close()

+ func (ty *FuncType) Params() []*ValType

+ func (ty *FuncType) Results() []*ValType

+ type Global struct

+ func NewGlobal(store Storelike, ty *GlobalType, val Val) (*Global, error)

+ func (g *Global) AsExtern() C.wasmtime_extern_t

+ func (g *Global) Get(store Storelike) Val

+ func (g *Global) Set(store Storelike, val Val) error

+ func (g *Global) Type(store Storelike) *GlobalType

+ type GlobalType struct

+ func NewGlobalType(content *ValType, mutable bool) *GlobalType

+ func (ty *GlobalType) AsExternType() *ExternType

+ func (ty *GlobalType) Close()

+ func (ty *GlobalType) Content() *ValType

+ func (ty *GlobalType) Mutable() bool

+ type ImportType struct

+ func NewImportType(module, name string, ty AsExternType) *ImportType

+ func (ty *ImportType) Close()

+ func (ty *ImportType) Module() string

+ func (ty *ImportType) Name() *string

+ func (ty *ImportType) Type() *ExternType

+ type Instance struct

+ func NewInstance(store Storelike, module *Module, imports []AsExtern) (*Instance, error)

+ func (i *Instance) GetExport(store Storelike, name string) *Extern

+ func (i *Instance) GetFunc(store Storelike, name string) *Func

+ func (instance *Instance) Exports(store Storelike) []*Extern

+ type Linker struct

+ Engine *Engine

+ func NewLinker(engine *Engine) *Linker

+ func (l *Linker) AllowShadowing(allow bool)

+ func (l *Linker) Close()

+ func (l *Linker) Define(store Storelike, module, name string, item AsExtern) error

+ func (l *Linker) DefineFunc(store Storelike, module, name string, f interface{}) error

+ func (l *Linker) DefineInstance(store Storelike, module string, instance *Instance) error

+ func (l *Linker) DefineModule(store Storelike, name string, module *Module) error

+ func (l *Linker) DefineUnknownImportsAsDefaultValues(store Storelike, module *Module) error

+ func (l *Linker) DefineUnknownImportsAsTraps(module *Module) error

+ func (l *Linker) DefineWasi() error

+ func (l *Linker) FuncNew(module, name string, ty *FuncType, f func(*Caller, []Val) ([]Val, *Trap)) error

+ func (l *Linker) FuncWrap(module, name string, f interface{}) error

+ func (l *Linker) Get(store Storelike, module, name string) *Extern

+ func (l *Linker) GetDefault(store Storelike, name string) (*Func, error)

+ func (l *Linker) Instantiate(store Storelike, module *Module) (*Instance, error)

+ type Memory struct

+ func NewMemory(store Storelike, ty *MemoryType) (*Memory, error)

+ func (mem *Memory) AsExtern() C.wasmtime_extern_t

+ func (mem *Memory) Data(store Storelike) unsafe.Pointer

+ func (mem *Memory) DataSize(store Storelike) uintptr

+ func (mem *Memory) Grow(store Storelike, delta uint64) (uint64, error)

+ func (mem *Memory) Size(store Storelike) uint64

+ func (mem *Memory) Type(store Storelike) *MemoryType

+ func (mem *Memory) UnsafeData(store Storelike) []byte

+ type MemoryType struct

+ func NewMemoryType(min uint32, has_max bool, max uint32, shared bool) (*MemoryType, error)

+ func NewMemoryType64(min uint64, has_max bool, max uint64, shared bool) (*MemoryType, error)

+ func (ty *MemoryType) AsExternType() *ExternType

+ func (ty *MemoryType) Close()

+ func (ty *MemoryType) Is64() bool

+ func (ty *MemoryType) IsShared() bool

+ func (ty *MemoryType) Maximum() (bool, uint64)

+ func (ty *MemoryType) Minimum() uint64

+ type Module struct

+ func NewModule(engine *Engine, wasm []byte) (*Module, error)

+ func NewModuleDeserialize(engine *Engine, encoded []byte) (*Module, error)

+ func NewModuleDeserializeFile(engine *Engine, path string) (*Module, error)

+ func NewModuleFromFile(engine *Engine, file string) (*Module, error)

+ func (m *Module) Close()

+ func (m *Module) Exports() []*ExportType

+ func (m *Module) Imports() []*ImportType

+ func (m *Module) Serialize() ([]byte, error)

+ type OptLevel C.wasmtime_opt_level_t

+ const OptLevelNone

+ const OptLevelSpeed

+ const OptLevelSpeedAndSize

+ type ProfilingStrategy C.wasmtime_profiling_strategy_t

+ const ProfilingStrategyJitdump

+ const ProfilingStrategyNone

+ type Store struct

+ Engine *Engine

+ func NewStore(engine *Engine) *Store

+ func NewStoreWithData(engine *Engine, data interface{}) *Store

+ func (store *Store) Close()

+ func (store *Store) Context() *C.wasmtime_context_t

+ func (store *Store) Data() interface{}

+ func (store *Store) GC()

+ func (store *Store) GetFuel() (uint64, error)

+ func (store *Store) Limiter(memorySize int64, tableElements int64, instances int64, tables int64, ...)

+ func (store *Store) SetEpochDeadline(deadline uint64)

+ func (store *Store) SetFuel(fuel uint64) error

+ func (store *Store) SetWasi(wasi *WasiConfig)

+ type Storelike interface

+ Context func() *C.wasmtime_context_t

+ Data func() interface{}

+ type Strategy C.wasmtime_strategy_t

+ const StrategyAuto

+ const StrategyCranelift

+ type Table struct

+ func NewTable(store Storelike, ty *TableType, init Val) (*Table, error)

+ func (t *Table) AsExtern() C.wasmtime_extern_t

+ func (t *Table) Get(store Storelike, idx uint64) (Val, error)

+ func (t *Table) Grow(store Storelike, delta uint64, init Val) (uint64, error)

+ func (t *Table) Set(store Storelike, idx uint64, val Val) error

+ func (t *Table) Size(store Storelike) uint64

+ func (t *Table) Type(store Storelike) *TableType

+ type TableType struct

+ func NewTableType(element *ValType, min uint32, has_max bool, max uint32) *TableType

+ func (ty *TableType) AsExternType() *ExternType

+ func (ty *TableType) Close()

+ func (ty *TableType) Element() *ValType

+ func (ty *TableType) Maximum() (bool, uint32)

+ func (ty *TableType) Minimum() uint32

+ type Trap struct

+ func NewTrap(message string) *Trap

+ func (t *Trap) Close()

+ func (t *Trap) Code() *TrapCode

+ func (t *Trap) Error() string

+ func (t *Trap) Frames() []*Frame

+ func (t *Trap) Message() string

+ type TrapCode uint8

+ const BadConversionToInteger

+ const BadSignature

+ const HeapMisaligned

+ const IndirectCallToNull

+ const IntegerDivisionByZero

+ const IntegerOverflow

+ const Interrupt

+ const MemoryOutOfBounds

+ const OutOfFuel

+ const StackOverflow

+ const TableOutOfBounds

+ const UnreachableCodeReached

+ type Val struct

+ func ValExternref(val interface{}) Val

+ func ValF32(val float32) Val

+ func ValF64(val float64) Val

+ func ValFuncref(f *Func) Val

+ func ValI32(val int32) Val

+ func ValI64(val int64) Val

+ func (v Val) Externref() interface{}

+ func (v Val) F32() float32

+ func (v Val) F64() float64

+ func (v Val) Funcref() *Func

+ func (v Val) Get() interface{}

+ func (v Val) I32() int32

+ func (v Val) I64() int64

+ func (v Val) Kind() ValKind

+ type ValKind C.wasm_valkind_t

+ const KindExternref

+ const KindF32

+ const KindF64

+ const KindFuncref

+ const KindI32

+ const KindI64

+ func (ty ValKind) String() string

+ type ValType struct

+ func NewValType(kind ValKind) *ValType

+ func (t *ValType) Kind() ValKind

+ func (t *ValType) String() string

+ func (ty *ValType) Close()

+ type WasiConfig struct

+ func NewWasiConfig() *WasiConfig

+ func (c *WasiConfig) Close()

+ func (c *WasiConfig) InheritArgv()

+ func (c *WasiConfig) InheritEnv()

+ func (c *WasiConfig) InheritStderr()

+ func (c *WasiConfig) InheritStdin()

+ func (c *WasiConfig) InheritStdout()

+ func (c *WasiConfig) PreopenDir(path, guestPath string, dirPerms WasiDirPerms, filePerms WasiFilePerms) error

+ func (c *WasiConfig) SetArgv(argv []string)

+ func (c *WasiConfig) SetEnv(keys, values []string)

+ func (c *WasiConfig) SetStderrFile(path string) error

+ func (c *WasiConfig) SetStdinFile(path string) error

+ func (c *WasiConfig) SetStdoutFile(path string) error

+ type WasiDirPerms uint8

+ type WasiFilePerms uint8

Other modules containing this package

github.com/bytecodealliance/wasmtime-go

github.com/bytecodealliance/wasmtime-go/v11

github.com/bytecodealliance/wasmtime-go/v12

github.com/bytecodealliance/wasmtime-go/v13

github.com/bytecodealliance/wasmtime-go/v14

github.com/bytecodealliance/wasmtime-go/v15

github.com/bytecodealliance/wasmtime-go/v16

github.com/bytecodealliance/wasmtime-go/v17

github.com/bytecodealliance/wasmtime-go/v18

github.com/bytecodealliance/wasmtime-go/v19

github.com/bytecodealliance/wasmtime-go/v20

github.com/bytecodealliance/wasmtime-go/v21

github.com/bytecodealliance/wasmtime-go/v22

github.com/bytecodealliance/wasmtime-go/v23

github.com/bytecodealliance/wasmtime-go/v24

github.com/bytecodealliance/wasmtime-go/v25

github.com/bytecodealliance/wasmtime-go/v27

github.com/bytecodealliance/wasmtime-go/v28

github.com/bytecodealliance/wasmtime-go/v29

github.com/bytecodealliance/wasmtime-go/v3

github.com/bytecodealliance/wasmtime-go/v30

github.com/bytecodealliance/wasmtime-go/v31

github.com/bytecodealliance/wasmtime-go/v32

github.com/bytecodealliance/wasmtime-go/v33

github.com/bytecodealliance/wasmtime-go/v34

github.com/bytecodealliance/wasmtime-go/v35

github.com/bytecodealliance/wasmtime-go/v36

github.com/bytecodealliance/wasmtime-go/v37

github.com/bytecodealliance/wasmtime-go/v38

github.com/bytecodealliance/wasmtime-go/v39

github.com/bytecodealliance/wasmtime-go/v4

github.com/bytecodealliance/wasmtime-go/v40

github.com/bytecodealliance/wasmtime-go/v41

github.com/bytecodealliance/wasmtime-go/v42

github.com/bytecodealliance/wasmtime-go/v5

github.com/bytecodealliance/wasmtime-go/v6

github.com/bytecodealliance/wasmtime-go/v7

github.com/bytecodealliance/wasmtime-go/v8

github.com/bytecodealliance/wasmtime-go/v9