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lockstep

package module

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Versions in this module

v0

v0.2.0

Nov 1, 2026

Changes in this version

type Context

+ func (c *Context[M]) Logger() *slog.Logger

+ type Counter interface

+ Add func(n uint64)

+ type MetricLabel struct

+ Name string

+ Value string

+ type Metrics interface

+ Counter func(name, help string, labels ...MetricLabel) Counter

+ GaugeFunc func(name, help string, fn func() int64, labels ...MetricLabel)

type Option

+ func WithEffectPool(workers, queue int) Option

+ func WithLogger(l *slog.Logger) Option

+ func WithMetrics(m Metrics) Option

+ func WithThroughput(n int) Option

+ func WithWorkers(n int) Option

type SpawnOption

+ func WithActorThroughput(n int) SpawnOption

v0.1.0

Oct 25, 2026

Changes in this version

+ const DefaultEffectTimeout

+ const DefaultGoroutineWarning

+ const DefaultMaxActors

+ const DefaultWatchdogTimeout

+ var ErrActorCap = errors.New("lockstep: actor cap reached")

+ var ErrAwaitInActor = errors.New("lockstep: blocking wait inside an actor")

+ var ErrInvalidName = errors.New("lockstep: invalid name")

+ var ErrInvalidOption = errors.New("lockstep: invalid option")

+ var ErrMailboxFull = errors.New("lockstep: mailbox full")

+ var ErrNameTaken = errors.New("lockstep: name taken")

+ var ErrNoEffectHandler = errors.New("lockstep: no effect handler")

+ var ErrNotFound = errors.New("lockstep: not found")

+ var ErrNotLocal = errors.New("lockstep: address not local")

+ var ErrOverloaded = engine.ErrOverloaded

+ var ErrStopped = errors.New("lockstep: stopped")

+ var ErrTerminated = errors.New("lockstep: actor terminated")

+ var ErrTimeout = errors.New("lockstep: timeout")

+ var ErrWrongType = errors.New("lockstep: wrong message type")

+ var NoActor = StopReason

+ var Normal = StopReason

+ var ParentStopping = StopReason

+ var Shutdown = StopReason

+ func NewReply[R any](from Sender, opts ...AskOption) (ReplyTo[R], *Reply[R])

+ func Pipe[R, M any](ctx *Context[M], r *Reply[R], to func(R, error) M)

+ func SendContext[M any](ctx context.Context, from Sender, to PID[M], msg M) error

+ func Send[M any](from Sender, to PID[M], msg M) error

+ func Stop(from Sender, addr Address) error

+ func Unwatch[M any](ctx *Context[M], addr Address)

+ func Watch[M any](ctx *Context[M], addr Address) error

+ type Actor interface

+ Receive func(ctx *Context[M], msg M)

+ type ActorEstimate struct

+ Addr Address

+ MailboxBytes int64

+ StateBytes int64

+ type Address struct

+ func (a Address) IsZero() bool

+ func (a Address) Node() string

+ func (a Address) Path() string

+ func (a Address) String() string

+ func (a Address) UID() uint64

+ type AskOption func(*askConfig)

+ func WithTimeout(d time.Duration) AskOption

+ type ChildFailed struct

+ Child Address

+ Cleanup bool

+ Directive Directive

+ Err error

+ type Context struct

+ func (c *Context[M]) After(d time.Duration, msg M) TimerID

+ func (c *Context[M]) CancelEffect(id EffectID) bool

+ func (c *Context[M]) CancelTimer(id TimerID) bool

+ func (c *Context[M]) Every(d time.Duration, msg M) TimerID

+ func (c *Context[M]) Fail(err error)

+ func (c *Context[M]) Logf(format string, args ...any)

+ func (c *Context[M]) Now() time.Time

+ func (c *Context[M]) Own(r io.Closer)

+ func (c *Context[M]) Parent() Address

+ func (c *Context[M]) Rand() *rand.Rand

+ func (c *Context[M]) Self() PID[M]

+ func (c *Context[M]) Stop()

+ func (c *Context[M]) SubscribeOverload()

+ func (c *Context[M]) UnsubscribeOverload()

+ type Directive uint8

+ const DirectiveEscalate

+ const DirectiveRestart

+ const DirectiveResume

+ const DirectiveStop

+ func (d Directive) String() string

+ type Effect interface

+ Name func() string

+ Run func(ctx context.Context) (T, error)

+ type EffectID uint64

+ func Do[T, M any](ctx *Context[M], e Effect[T], done func(T, error) M, opts ...EffectOption) EffectID

+ type EffectOption func(*effectConfig)

+ func WithEffectTimeout(d time.Duration) EffectOption

+ type MailboxPolicy uint8

+ const BlockSender

+ const DropNewest

+ const DropOldest

+ const FailSend

+ func (p MailboxPolicy) String() string

+ type MemSizer interface

+ MemSize func() int

+ type Option func(*systemConfig)

+ func WithAdmission(high, low uint64) Option

+ func WithDefaultMailbox(capacity int, policy MailboxPolicy) Option

+ func WithGoroutineWarning(bound int) Option

+ func WithGuardianStrategy(s Strategy) Option

+ func WithMaxActors(n int) Option

+ func WithMemoryEstimates() Option

+ func WithNodeName(name string) Option

+ func WithWatchdog(d time.Duration) Option

+ type OverloadReason uint8

+ const OverloadBudget

+ const OverloadMemory

+ const OverloadPressure

+ func (r OverloadReason) String() string

+ type Overloaded struct

+ Active bool

+ High uint64

+ Live uint64

+ Low uint64

+ Reason OverloadReason

+ type PID struct

+ func Lookup[M any](sys *System, path string) (PID[M], error)

+ func PIDAt[M any](node, path string) PID[M]

+ func Spawn[M any](parent Spawner, name string, factory func() Actor[M], opts ...SpawnOption) (PID[M], error)

+ func (p PID[M]) Address() Address

+ func (p PID[M]) IsZero() bool

+ func (p PID[M]) String() string

+ type PanicError struct

+ Stack []byte

+ Value any

+ func (e *PanicError) Error() string

+ func (e *PanicError) Unwrap() error

+ type Reply struct

+ func Ask[M, R any](from Sender, to PID[M], build func(ReplyTo[R]) M, opts ...AskOption) *Reply[R]

+ func (r *Reply[R]) Await(ctx context.Context) (R, error)

+ type ReplyTo struct

+ func (rt ReplyTo[R]) Fail(from Sender, err error)

+ func (rt ReplyTo[R]) Send(from Sender, v R)

+ type Sender interface

+ type Signal interface

+ type SignalReceiver interface

+ Signal func(ctx *Context[M], sig Signal)

+ type Sizer interface

+ Size func() int

+ type SpawnOption func(*spawnConfig)

+ func WithMailbox(capacity int, policy MailboxPolicy) SpawnOption

+ func WithStrategy(s Strategy) SpawnOption

+ type Spawner interface

+ type Starter interface

+ Started func(ctx *Context[M])

+ type StopKind uint8

+ const StopFailed

+ const StopNoActor

+ const StopNormal

+ const StopParentStopping

+ const StopRestarting

+ const StopShutdown

+ func (k StopKind) String() string

+ type StopReason struct

+ Err error

+ Kind StopKind

+ func Failed(err error) StopReason

+ func Restarting(err error) StopReason

+ func (r StopReason) String() string

+ type Stopper interface

+ Stopped func(ctx *Context[M], reason StopReason)

+ type Strategy struct

+ Decider func(err error) Directive

+ MaxBackoff time.Duration

+ MaxRestarts int

+ MinBackoff time.Duration

+ Window time.Duration

+ func AllForOne(decider func(err error) Directive) Strategy

+ func OneForOne(decider func(err error) Directive) Strategy

+ type System struct

+ func New(opts ...Option) *System

+ func (s *System) Estimates(n int) []ActorEstimate

+ func (s *System) Incarnation() uint32

+ func (s *System) Node() string

+ func (s *System) Shutdown(ctx context.Context) error

+ type Terminated struct

+ Addr Address

+ Reason StopReason

+ type TimerID uint64