diff --git a/adapter/redis_collection_fastpath_test.go b/adapter/redis_collection_fastpath_test.go
index 42f40a6a..80c75dec 100644
--- a/adapter/redis_collection_fastpath_test.go
+++ b/adapter/redis_collection_fastpath_test.go
@@ -2,6 +2,7 @@ package adapter
 
 import (
 	"context"
+	"errors"
 	"testing"
 	"time"
 
@@ -30,14 +31,6 @@ import (
 
 const collectionFastPathTTL = 80 * time.Millisecond
 
-// waitForTTLExpiry sleeps past a short TTL so the next read sees the
-// key as expired. A small headroom accounts for wall-clock jitter on
-// CI; tests that are sensitive to this use short TTLs (~80 ms) so the
-// delay stays well under a second.
-func waitForTTLExpiry() {
-	time.Sleep(collectionFastPathTTL + 50*time.Millisecond)
-}
-
 func TestRedis_HGET_FastPathHit(t *testing.T) {
 	t.Parallel()
 	nodes, _, _ := createNode(t, 3)
@@ -107,10 +100,10 @@ func TestRedis_HGET_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.HSet(ctx, "h:ttl", "field", "value").Err())
 	require.NoError(t, rdb.PExpire(ctx, "h:ttl", collectionFastPathTTL).Err())
-	waitForTTLExpiry()
-
-	_, err := rdb.HGet(ctx, "h:ttl", "field").Result()
-	require.ErrorIs(t, err, redis.Nil, "HGET on an expired hash must return nil")
+	eventuallyExpired(t, collectionFastPathTTL, func() bool {
+		_, err := rdb.HGet(ctx, "h:ttl", "field").Result()
+		return errors.Is(err, redis.Nil)
+	}, "HGET on an expired hash must return nil")
 }
 
 func TestRedis_HEXISTS_FastPathHit(t *testing.T) {
@@ -184,11 +177,10 @@ func TestRedis_HEXISTS_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.HSet(ctx, "he:ttl", "field", "v").Err())
 	require.NoError(t, rdb.PExpire(ctx, "he:ttl", collectionFastPathTTL).Err())
-	waitForTTLExpiry()
-
-	ok, err := rdb.HExists(ctx, "he:ttl", "field").Result()
-	require.NoError(t, err)
-	require.False(t, ok, "HEXISTS on an expired hash must return 0")
+	eventuallyExpired(t, collectionFastPathTTL, func() bool {
+		ok, err := rdb.HExists(ctx, "he:ttl", "field").Result()
+		return err == nil && !ok
+	}, "HEXISTS on an expired hash must return 0")
 }
 
 func TestRedis_SISMEMBER_FastPathHit(t *testing.T) {
@@ -262,11 +254,10 @@ func TestRedis_SISMEMBER_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.SAdd(ctx, "s:ttl", "member").Err())
 	require.NoError(t, rdb.PExpire(ctx, "s:ttl", collectionFastPathTTL).Err())
-	waitForTTLExpiry()
-
-	ok, err := rdb.SIsMember(ctx, "s:ttl", "member").Result()
-	require.NoError(t, err)
-	require.False(t, ok, "SISMEMBER on an expired set must return 0")
+	eventuallyExpired(t, collectionFastPathTTL, func() bool {
+		ok, err := rdb.SIsMember(ctx, "s:ttl", "member").Result()
+		return err == nil && !ok
+	}, "SISMEMBER on an expired set must return 0")
 }
 
 // TestRedis_HGET_FastPathGuardDualEncoding exercises the string-
diff --git a/adapter/redis_lua_collection_fastpath_test.go b/adapter/redis_lua_collection_fastpath_test.go
index 2494a5c4..bb461f37 100644
--- a/adapter/redis_lua_collection_fastpath_test.go
+++ b/adapter/redis_lua_collection_fastpath_test.go
@@ -2,6 +2,7 @@ package adapter
 
 import (
 	"context"
+	"errors"
 	"math"
 	"strconv"
 	"testing"
@@ -29,10 +30,6 @@ import (
 
 const luaFastPathTTL = 80 * time.Millisecond
 
-func waitForLuaTTL() {
-	time.Sleep(luaFastPathTTL + 50*time.Millisecond)
-}
-
 func TestLua_HGET_FastPathHit(t *testing.T) {
 	t.Parallel()
 	nodes, _, _ := createNode(t, 3)
@@ -117,13 +114,13 @@ func TestLua_HGET_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.HSet(ctx, "lua:h:ttl", "field", "v").Err())
 	require.NoError(t, rdb.PExpire(ctx, "lua:h:ttl", luaFastPathTTL).Err())
-	waitForLuaTTL()
-
-	_, err := rdb.Eval(ctx,
-		`return redis.call("HGET", KEYS[1], "field")`,
-		[]string{"lua:h:ttl"},
-	).Result()
-	require.ErrorIs(t, err, redis.Nil, "HGET on an expired hash from Lua must surface as nil")
+	eventuallyExpired(t, luaFastPathTTL, func() bool {
+		_, err := rdb.Eval(ctx,
+			`return redis.call("HGET", KEYS[1], "field")`,
+			[]string{"lua:h:ttl"},
+		).Result()
+		return errors.Is(err, redis.Nil)
+	}, "HGET on an expired hash from Lua must surface as nil")
 }
 
 func TestLua_HEXISTS_FastPathHit(t *testing.T) {
@@ -190,14 +187,13 @@ func TestLua_HEXISTS_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.HSet(ctx, "lua:he:ttl", "f", "v").Err())
 	require.NoError(t, rdb.PExpire(ctx, "lua:he:ttl", luaFastPathTTL).Err())
-	waitForLuaTTL()
-
-	got, err := rdb.Eval(ctx,
-		`return redis.call("HEXISTS", KEYS[1], "f")`,
-		[]string{"lua:he:ttl"},
-	).Result()
-	require.NoError(t, err)
-	require.Equal(t, int64(0), got)
+	eventuallyExpired(t, luaFastPathTTL, func() bool {
+		got, err := rdb.Eval(ctx,
+			`return redis.call("HEXISTS", KEYS[1], "f")`,
+			[]string{"lua:he:ttl"},
+		).Result()
+		return err == nil && got == int64(0)
+	}, "HEXISTS on an expired hash from Lua must return 0")
 }
 
 func TestLua_SISMEMBER_FastPathHit(t *testing.T) {
@@ -553,13 +549,13 @@ func TestLua_ZSCORE_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.ZAdd(ctx, "lua:z:ttl", redis.Z{Score: 1, Member: "m"}).Err())
 	require.NoError(t, rdb.PExpire(ctx, "lua:z:ttl", luaFastPathTTL).Err())
-	waitForLuaTTL()
-
-	_, err := rdb.Eval(ctx,
-		`return redis.call("ZSCORE", KEYS[1], "m")`,
-		[]string{"lua:z:ttl"},
-	).Result()
-	require.ErrorIs(t, err, redis.Nil)
+	eventuallyExpired(t, luaFastPathTTL, func() bool {
+		_, err := rdb.Eval(ctx,
+			`return redis.call("ZSCORE", KEYS[1], "m")`,
+			[]string{"lua:z:ttl"},
+		).Result()
+		return errors.Is(err, redis.Nil)
+	}, "ZSCORE on an expired zset from Lua must return nil")
 }
 
 func TestLua_ZSCORE_SetThenZScoreReturnsWrongType(t *testing.T) {
@@ -847,14 +843,14 @@ func TestLua_ZRANGEBYSCORE_TTLExpired(t *testing.T) {
 
 	require.NoError(t, rdb.ZAdd(ctx, "lua:zr:ttl", redis.Z{Score: 1, Member: "m"}).Err())
 	require.NoError(t, rdb.PExpire(ctx, "lua:zr:ttl", luaFastPathTTL).Err())
-	waitForLuaTTL()
-
-	got, err := rdb.Eval(ctx,
-		`return redis.call("ZRANGEBYSCORE", KEYS[1], "-inf", "+inf")`,
-		[]string{"lua:zr:ttl"},
-	).Result()
-	require.NoError(t, err)
-	require.Equal(t, []any{}, got)
+	eventuallyExpired(t, luaFastPathTTL, func() bool {
+		got, err := rdb.Eval(ctx,
+			`return redis.call("ZRANGEBYSCORE", KEYS[1], "-inf", "+inf")`,
+			[]string{"lua:zr:ttl"},
+		).Result()
+		gotArr, ok := got.([]any)
+		return err == nil && ok && len(gotArr) == 0
+	}, "ZRANGEBYSCORE on an expired zset from Lua must return an empty array")
 }
 
 // --- Correctness regressions surfaced by PR #570 review ---
diff --git a/adapter/redis_misskey_compat_test.go b/adapter/redis_misskey_compat_test.go
index e7e7d30a..44cd998f 100644
--- a/adapter/redis_misskey_compat_test.go
+++ b/adapter/redis_misskey_compat_test.go
@@ -2,6 +2,7 @@ package adapter
 
 import (
 	"context"
+	"errors"
 	"testing"
 	"time"
 
@@ -43,8 +44,15 @@ func TestRedis_MisskeyConnectionCompatibility(t *testing.T) {
 	require.NoError(t, err)
 	require.Greater(t, pttl, time.Duration(0))
 
-	time.Sleep(1100 * time.Millisecond)
-	require.ErrorIs(t, rdb.Get(ctx, "lock:ap-object").Err(), redis.Nil)
+	// The "lock:ap-object" key was just SET with EX 1 (1-second TTL).
+	// Wait for it to expire via the deadline-multiplier helper rather
+	// than a fixed time.Sleep — the previous Sleep(1100ms) raced CI
+	// scheduler jitter on slow runners (the post-sleep GET could fire
+	// before the TTL had actually been processed by the sweeper).
+	const lockTTL = 1 * time.Second
+	eventuallyExpired(t, lockTTL, func() bool {
+		return errors.Is(rdb.Get(ctx, "lock:ap-object").Err(), redis.Nil)
+	}, "lock:ap-object must be gone after its 1-second EX TTL")
 }
 
 func TestRedis_MisskeyPubSubCompatibility(t *testing.T) {
diff --git a/adapter/test_util.go b/adapter/test_util.go
index ba88cfef..744249a6 100644
--- a/adapter/test_util.go
+++ b/adapter/test_util.go
@@ -707,6 +707,49 @@ func isTransientNotLeaderErr(err error) bool {
 	return strings.Contains(s, "not leader") || strings.Contains(s, "leader not found")
 }
 
+// === TTL-expiry deadline-multiplier helper =============================
+//
+// Redis TTL tests that "set a short TTL, sleep past it, assert the key is
+// gone" race their own wall clock under -race on slow CI runners. The
+// inter-call pause (typically 50–150 ms above the TTL) does not absorb
+// scheduler jitter that can push the post-sleep read past the TTL window
+// itself, so the read sometimes observes a refilled/un-expired view and
+// the test fails with "expected redis.Nil, got <value>". PR #818
+// (TestRedis_ExpiredKey_BecomesInvisible) fixed one instance by switching
+// to require.Eventually with a TTL-derived deadline. eventuallyExpired
+// generalises that pattern for any TTL-expiry condition.
+//
+// Use this helper in any new test of the form:
+//
+//	require.NoError(t, rdb.PExpire(ctx, key, ttl).Err())
+//	eventuallyExpired(t, ttl, func() bool {
+//	    _, err := rdb.<Op>(ctx, key, ...).Result()
+//	    return errors.Is(err, redis.Nil)
+//	}, "key must be gone after TTL")
+//
+// instead of `time.Sleep(ttl + N*time.Millisecond)` followed by a single
+// assertion. The deadline = ttl + 3 s gives generous CI headroom; the
+// 25 ms poll cadence matches waitForStableLeader so flake patterns stay
+// uniform across the file.
+func eventuallyExpired(t *testing.T, ttl time.Duration, condition func() bool, msg string) {
+	t.Helper()
+	const (
+		ttlExpiryHeadroom = 3 * time.Second
+		ttlExpiryPoll     = 25 * time.Millisecond
+	)
+	// Sleep past the TTL before the first poll. require.Eventually
+	// runs the condition once IMMEDIATELY before the first tick, so
+	// without this gate a regression that deletes/hides the key at
+	// PExpire time would satisfy the first poll and the test would
+	// never exercise the actual expired-after-deadline state — see
+	// codex P2 on PR #903. The post-sleep require.Eventually then
+	// has ttlExpiryHeadroom (3 s) of CI-jitter slack to observe the
+	// expired state, with a 25 ms poll cadence that matches
+	// waitForStableLeader's sampler so flake patterns stay uniform.
+	time.Sleep(ttl)
+	require.Eventually(t, condition, ttlExpiryHeadroom, ttlExpiryPoll, msg)
+}
+
 // doEventually retries do() while it returns a transient "not leader" error,
 // giving the cluster a few seconds to re-settle leadership after startup.
 // Non-"not leader" errors fail the test immediately.