effect-time-tracing-logging

• You need timeouts, deadlines, or sleeps
• You want spans for latency analysis or logs for debugging

```ts

import { Clock, Duration } from "effect"

const now = yield* Clock.currentTimeMillis

yield* Effect.sleep(Duration.seconds(1))

```

```ts

const guarded = yield* Effect.timeout(task, Duration.seconds(2))

```

```ts

const op = Effect.withSpan("operation")(Effect.succeed(1))

```

```ts

yield* Effect.logInfo("message")

yield* Effect.logDebug("debug")

yield* Effect.logError("error")

```

```ts

import { Effect, Option, Logger, LogLevel, Layer } from "effect"

export const setMinimumLogLevel = (cliLevel: Option.Option) =>

APP_CONFIG["LOG_LEVEL"].pipe(

Effect.map((envLevel) => Option.zipLeft(cliLevel, envLevel)),

Effect.map(Option.getOrElse(() => LogLevel.Info)),

Effect.map((level) => Logger.minimumLogLevel(level)),

Layer.unwrapEffect

)

```

• Prefer Duration helpers for clarity of units
• Wrap critical sections with spans; attach attributes for context
• Use structured logs and avoid ad-hoc console prints

• Mixing ms numbers → use Duration consistently
• No timeouts on external calls → risk of hanging operations

• Errors & Retries for timeouts+races
• Concurrency for coordinated time-based operations

CRITICAL: Search local Effect source before implementing

The full Effect source code is available at docs/effect-source/. Always search the actual implementation before writing Effect code.

Key Source Files

• Clock: docs/effect-source/effect/src/Clock.ts
• Duration: docs/effect-source/effect/src/Duration.ts
• Effect (withSpan, log): docs/effect-source/effect/src/Effect.ts
• Logger: docs/effect-source/effect/src/Logger.ts
• LogLevel: docs/effect-source/effect/src/LogLevel.ts

Example Searches

```bash

# Find Clock operations

grep -F "currentTimeMillis" docs/effect-source/effect/src/Clock.ts

grep -F "sleep" docs/effect-source/effect/src/Clock.ts

# Study Duration helpers

grep -F "seconds" docs/effect-source/effect/src/Duration.ts

grep -F "millis" docs/effect-source/effect/src/Duration.ts

grep -F "minutes" docs/effect-source/effect/src/Duration.ts

# Find span and logging patterns

grep -F "withSpan" docs/effect-source/effect/src/Effect.ts

grep -F "logInfo" docs/effect-source/effect/src/Effect.ts

grep -F "logError" docs/effect-source/effect/src/Effect.ts

# Look at Logger implementation

grep -F "minimumLogLevel" docs/effect-source/effect/src/Logger.ts

```

Workflow

1. Identify the time/logging API you need (e.g., Clock, Duration, withSpan)
2. Search docs/effect-source/effect/src/ for the implementation
3. Study the types and time-based patterns
4. Look at test files for usage examples
5. Write your code based on real implementations

Real source code > documentation > assumptions

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