From c71c1d1d3cc55b928d7a37193d054f36bef2fc34 Mon Sep 17 00:00:00 2001
From: Sebastian Lorenz <fubhy@fubhy.com>
Date: Sat, 1 Aug 2026 18:41:12 +0000
Subject: [PATCH 1/2] Add reproduction for Schedule issue

---
 packages/effect/test/Schedule.test.ts | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/packages/effect/test/Schedule.test.ts b/packages/effect/test/Schedule.test.ts
index 7200df6f4b5..50a4dc56c75 100644
--- a/packages/effect/test/Schedule.test.ts
+++ b/packages/effect/test/Schedule.test.ts
@@ -4,6 +4,19 @@ import { constant, constUndefined } from "effect/Function"
 import { TestClock } from "effect/testing"
 
 describe("Schedule", () => {
+  describe("constructors", () => {
+    it.effect("during recurs while the duration has not elapsed", () =>
+      Effect.gen(function*() {
+        const step = yield* Schedule.toStep(Schedule.during("1 second"))
+        const completed = yield* Pull.catchDone(
+          step(0, undefined).pipe(Effect.as(false)),
+          () => Effect.succeed(true)
+        )
+
+        assert.isFalse(completed)
+      }))
+  })
+
   describe("combining", () => {
     it.effect("max - outputs the slowest schedule duration", () =>
       Effect.gen(function*() {

From 18b3f1e3ea42f72ba2a0676e4d1ac53e1f53cd4e Mon Sep 17 00:00:00 2001
From: Tim Smart <hello@timsmart.co>
Date: Mon, 3 Aug 2026 10:38:51 +1200
Subject: [PATCH 2/2] Fix Schedule.during recurrence condition

---
 .changeset/fix-schedule-during.md | 5 +++++
 packages/effect/src/Schedule.ts   | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/fix-schedule-during.md

diff --git a/.changeset/fix-schedule-during.md b/.changeset/fix-schedule-during.md
new file mode 100644
index 00000000000..c881221afe4
--- /dev/null
+++ b/.changeset/fix-schedule-during.md
@@ -0,0 +1,5 @@
+---
+"effect": patch
+---
+
+Fix `Schedule.during` to recur until the configured duration has elapsed.
diff --git a/packages/effect/src/Schedule.ts b/packages/effect/src/Schedule.ts
index 1e2f50d7ca8..68782b5eb7c 100644
--- a/packages/effect/src/Schedule.ts
+++ b/packages/effect/src/Schedule.ts
@@ -753,8 +753,8 @@ export const during = (duration: Duration.Input): Schedule<Duration.Duration> =>
     effect.succeed((meta) => {
       const elapsed = Duration.millis(meta.elapsed)
       return meta.elapsed > durationMillis
-        ? effect.succeed([elapsed, Duration.zero])
-        : Cause.done(elapsed)
+        ? Cause.done(elapsed)
+        : effect.succeed([elapsed, Duration.zero])
     })
   )
 }