igalshilman

/**
 * Standalone example: lazy conversation history with cold-prefix offload.
 *
 * ## What is stored
 *
 * Metadata and message segments are stored as independent values. `append`
 * and `offloadPrefix` opt into lazy state because they touch only selected
 * segments; `applyOffload` and `history` use eager state:
 *
 * - `history/meta` holds `messageSequence`, `headSegment`, `tailSegment`, and

igalshilman

/**
 * Standalone example: lazy conversation history with cold-prefix offload.
 *
 * ## What is stored
 *
 * Metadata and message segments are stored as independent values. `append`
 * and `offloadPrefix` opt into lazy state because they touch only selected
 * segments; `applyOffload` and `history` use eager state:
 *
 * - `history/meta` holds `messageSequence`, `headSegment`, `tailSegment`, and

igalshilman

import {
  service,
  serve,
  type Context,
  RestatePromise,
  TerminalError,
} from "@restatedev/restate-sdk";

type GeneratorState<T, TReturn> =
  | { type: "open"; gen: AsyncGenerator<T, TReturn> }

igalshilman

import {
  Operation,
  object,
  run,
} from "@restatedev/restate-sdk-gen";
import { serve } from "@restatedev/restate-sdk";
import OpenAI from "openai";
import * as utils from "./utils";

const openai = new OpenAI(); // reads OPENAI_API_KEY from the environment

igalshilman

import {
  Operation,
  object,
  service,
  invocation,
  sendClient,
  handlerRequest,
  run,
} from "@restatedev/restate-sdk-gen";
import { serve, InvocationId } from "@restatedev/restate-sdk";

igalshilman

Effect Handlers in TypeScript

OCaml-style algebraic effects built on TypeScript generators. The fiber holds the iterator and a small state machine. The continuation is a one-shot, safety-checked handle. The handler is an async scheduler that drains synchronously-runnable work and parks while external wakers are pending.

Three pieces, each with one job:

• Fiber<T> — iteration state machine

igalshilman

restate-sdk-gen internals: fibers, the scheduler, and the stack

A walkthrough of how user generators, fibers, and the scheduler interact in @restatedev/restate-sdk-gen. Aimed at JS engineers who already know Restate and durable execution; we skip framing on journals/replay and focus on the runtime model.

Source files referenced throughout:

• src/scheduler.ts — orchestration

igalshilman

RocksDB SIGTRAP on Apple Silicon: Hardened libc++ vs Custom Aligned Allocators

Summary

RocksDB crashes with SIGTRAP (EXC_BREAKPOINT, brk #0x1) on Apple Silicon (aarch64-apple-darwin) when statistics are enabled. The crash occurs inside StatisticsImpl::recordTick or StatisticsImpl::recordInHistogram during normal database operations, including DB::Open.

The root cause is an incompatibility between Apple Clang's hardened libc++ bounds checking and RocksDB's custom cache-line-aligned allocator used by StatisticsData.

Symptoms

igalshilman

R = typing.TypeVar('R', bound=typing.Callable[..., typing.Awaitable[typing.Any]])
P = typing.ParamSpec('P'
def handler(func):
    func._is_handler = True
    return func


class Box:
    __slots__ = ('value',)

igalshilman

import {
  service,
  serve,
  type Context,
  RestatePromise,
  TerminalError,
} from "@restatedev/restate-sdk";

/***
 * A durable async generator that persists its state across restarts.