diff --git a/packages/mcp/bootstrap.ts b/packages/mcp/bootstrap.ts
index 7deee12..e4586c3 100644
--- a/packages/mcp/bootstrap.ts
+++ b/packages/mcp/bootstrap.ts
@@ -571,7 +571,7 @@ export const deriveProject = (
   deps: DeriveProjectDeps,
 ): Effect.Effect<Option.Option<ProjectSlug>> => {
   if (deps.project !== undefined) {
-    return Effect.succeed(Option.some(deps.project))
+    return Effect.succeedSome(deps.project)
   }
   return Effect.map(deps.readGitContext(deps.cwd), (context) =>
     matchGitContext(context, {
@@ -604,7 +604,7 @@ const gitStdout = (
     Command.stderr('pipe'),
     Command.string,
     Effect.map((out) => out.trim()),
-    Effect.catchAll(() => Effect.succeed('')),
+    Effect.orElseSucceed(() => ''),
   )
 
 /**
diff --git a/packages/mcp/channels-catch-up.test.ts b/packages/mcp/channels-catch-up.test.ts
index 6778fb7..0e3c7f7 100644
--- a/packages/mcp/channels-catch-up.test.ts
+++ b/packages/mcp/channels-catch-up.test.ts
@@ -106,7 +106,7 @@ const buildHistorySpy = (
           return byThread[`${channel}/${threadName}`] ?? []
         }),
       recentThreads: () => Effect.succeed([]),
-      messagePermalink: () => Effect.succeed(Option.none()),
+      messagePermalink: () => Effect.succeedNone,
     },
   }
 }
diff --git a/packages/mcp/deployed-wiring.test.ts b/packages/mcp/deployed-wiring.test.ts
index b3a9f5b..3ebf1a0 100644
--- a/packages/mcp/deployed-wiring.test.ts
+++ b/packages/mcp/deployed-wiring.test.ts
@@ -219,11 +219,11 @@ const bootDeployedSeat = async (
   Deferred.unsafeDone(resumeOutcome, Effect.succeed(false))
   const sessionIdDeferred = Deferred.unsafeMake<SessionIdValue>(FiberId.none)
   const inMemoryCursorStore = {
-    read: () => Effect.succeed(Option.none()),
+    read: () => Effect.succeedNone,
     write: () => Effect.void,
   }
   const inMemorySubscriptionStore = {
-    read: () => Effect.succeed(Option.none()),
+    read: () => Effect.succeedNone,
     write: () => Effect.void,
   }
 
diff --git a/packages/mcp/disconnect-exit.fixture.ts b/packages/mcp/disconnect-exit.fixture.ts
index 4900a32..ef9eda0 100644
--- a/packages/mcp/disconnect-exit.fixture.ts
+++ b/packages/mcp/disconnect-exit.fixture.ts
@@ -21,7 +21,7 @@ import { memoryAdapter } from '@commy/memory/adapter'
 import { FetchHttpClient } from '@effect/platform'
 import { NodeContext, NodeRuntime } from '@effect/platform-node'
 import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js'
-import { ConfigProvider, Effect, Layer, Option } from 'effect'
+import { ConfigProvider, Effect, Layer } from 'effect'
 import { substrateAdapterLayer } from './bootstrap.ts'
 import { CursorStoreTag } from './cursor-store.ts'
 import { completeAsSubstrate } from './memory-substrate.ts'
@@ -33,12 +33,12 @@ import { SubscriptionStoreTag } from './subscription-store.ts'
 import { testBootStoresLayer } from './test-platform.ts'
 
 const inMemoryCursorStore = {
-  read: () => Effect.succeed(Option.none()),
+  read: () => Effect.succeedNone,
   write: () => Effect.void,
 }
 
 const inMemorySubscriptionStore = {
-  read: () => Effect.succeed(Option.none()),
+  read: () => Effect.succeedNone,
   write: () => Effect.void,
 }
 
diff --git a/packages/mcp/queue-state-hooks.ts b/packages/mcp/queue-state-hooks.ts
index c406c6c..1405f78 100644
--- a/packages/mcp/queue-state-hooks.ts
+++ b/packages/mcp/queue-state-hooks.ts
@@ -87,7 +87,7 @@ export const buildQueueStateHooks = (deps: {
               onNone: () =>
                 store.read(id).pipe(
                   Effect.map(Option.isNone),
-                  Effect.catchAll(() => Effect.succeed(true)),
+                  Effect.orElseSucceed(() => true),
                   Effect.flatMap((isFresh) => (isFresh ? store.write(id, queue) : Effect.void)),
                 ),
             }),
diff --git a/packages/mcp/queue-state-store.ts b/packages/mcp/queue-state-store.ts
index d607f17..a46216f 100644
--- a/packages/mcp/queue-state-store.ts
+++ b/packages/mcp/queue-state-store.ts
@@ -94,7 +94,7 @@ const readState = (
 ): Effect.Effect<Option.Option<EventQueueCursor>, PlatformError | ParseResult.ParseError> =>
   fs.readFileString(path).pipe(
     Effect.flatMap(decodeQueueStateFile),
-    Effect.map(Option.some),
+    Effect.asSome,
     Effect.catchIf(isNotFound, () => Effect.succeed(Option.none<EventQueueCursor>())),
   )
 
diff --git a/packages/mcp/server.integration.test.ts b/packages/mcp/server.integration.test.ts
index 4067032..37fd587 100644
--- a/packages/mcp/server.integration.test.ts
+++ b/packages/mcp/server.integration.test.ts
@@ -1367,7 +1367,7 @@ test('persistent boot with no prior cursor: no replay events fired, cursor initi
 test('persistent boot with a prior cursor: replay fires, mention-received notifications dispatched ahead of pump', async () => {
   const PRIOR_CURSOR_TS = 1000
   const cursorStore: CursorStore = {
-    read: () => Effect.succeed(Option.some(decodeTimestampSync(PRIOR_CURSOR_TS))),
+    read: () => Effect.succeedSome(decodeTimestampSync(PRIOR_CURSOR_TS)),
     write: () => Effect.void,
   }
 
@@ -1529,7 +1529,7 @@ test('ephemeral lazy acquire with no prior cursor: no replay, cursor initialised
 test('ephemeral lazy acquire with a prior cursor: replay fires, mention dispatched ahead of tool result', async () => {
   const PRIOR_CURSOR_TS = 1000
   const cursorStore: CursorStore = {
-    read: () => Effect.succeed(Option.some(decodeTimestampSync(PRIOR_CURSOR_TS))),
+    read: () => Effect.succeedSome(decodeTimestampSync(PRIOR_CURSOR_TS)),
     write: () => Effect.void,
   }
 
@@ -1615,7 +1615,7 @@ test('ephemeral lazy acquire with a prior cursor: replay fires, mention dispatch
 
 test('ephemeral catch-up failure is non-fatal: tool call succeeds, failure is logged', async () => {
   const cursorStore: CursorStore = {
-    read: () => Effect.succeed(Option.some(decodeTimestampSync(1000))),
+    read: () => Effect.succeedSome(decodeTimestampSync(1000)),
     write: () => Effect.void,
   }
 
@@ -1664,7 +1664,7 @@ test('ephemeral queue-ALIVE resume: history catch-up does NOT run, no duplicate
   // either would double-deliver every message the pump already carries.
   const PRIOR_CURSOR_TS = 1000
   const cursorStore: CursorStore = {
-    read: () => Effect.succeed(Option.some(decodeTimestampSync(PRIOR_CURSOR_TS))),
+    read: () => Effect.succeedSome(decodeTimestampSync(PRIOR_CURSOR_TS)),
     write: () => Effect.void,
   }
   const replayCalls: number[] = []
@@ -1720,7 +1720,7 @@ test('ephemeral queue-DEAD resume: mentions + channels catch-up run and backfill
   // messages the dead queue could not carry.
   const PRIOR_CURSOR_TS = 1000
   const cursorStore: CursorStore = {
-    read: () => Effect.succeed(Option.some(decodeTimestampSync(PRIOR_CURSOR_TS))),
+    read: () => Effect.succeedSome(decodeTimestampSync(PRIOR_CURSOR_TS)),
     write: () => Effect.void,
   }
   const mentionedIdentity = {
@@ -1997,7 +1997,7 @@ test('ephemeral subscribe persists the live narrow set (defaults + new sub) unde
   // keyed under that id with no id ever passed to write().
   const sessionIdDeferred = Deferred.unsafeMake<SessionIdValue>(FiberId.none)
   const subscriptionStore: SubscriptionStore = {
-    read: () => Effect.succeed(Option.none()),
+    read: () => Effect.succeedNone,
     write: (intents) =>
       Effect.flatMap(Deferred.await(sessionIdDeferred), (id) =>
         Effect.sync(() => {
@@ -2035,7 +2035,7 @@ test('ephemeral resume recovers its channels from the realm and does NOT re-appl
   // is what marks this a resume rather than a first launch. Resume must honour
   // both: recover `home`, and never re-add a dropped default.
   const subscriptionStore: SubscriptionStore = {
-    read: () => Effect.succeed(Option.some([])),
+    read: () => Effect.succeedSome([]),
     write: () => Effect.void,
   }
   const cap = captureSubscribes(['home'])
diff --git a/packages/mcp/server.test.ts b/packages/mcp/server.test.ts
index 04301dc..3b87ade 100644
--- a/packages/mcp/server.test.ts
+++ b/packages/mcp/server.test.ts
@@ -210,7 +210,7 @@ const buildFakeAdapter = (
         return Effect.succeed(acquiredIdentity)
       }),
     release: () => Effect.void,
-    resolve: () => Effect.succeed(Option.none()),
+    resolve: () => Effect.succeedNone,
   }
   const publisher: MessagePublisher = {
     post: () => Effect.die(new Error('unused fake')),
@@ -247,13 +247,13 @@ const buildFakeAdapter = (
     readChannel: (_channel: ChannelName, _range: Range) => Effect.succeed([]),
     readThread: (_channel: ChannelName, _threadName, _range?: Range) => Effect.succeed([]),
     recentThreads: () => Effect.succeed([]),
-    messagePermalink: () => Effect.succeed(Option.none()),
+    messagePermalink: () => Effect.succeedNone,
   }
   const directory: Directory = {
     listAgents: () => Effect.succeed([]),
     listHumans: () => Effect.succeed([]),
     listChannels: () => Effect.succeed([]),
-    channelDescription: () => Effect.succeed(Option.none()),
+    channelDescription: () => Effect.succeedNone,
     presence: (_id: Identity): Effect.Effect<Presence> => Effect.succeed('offline'),
   }
   const adapter = completeAsSubstrate(
@@ -532,20 +532,18 @@ test('boot completes for an ephemeral seat with COMMY_SUBSCRIBE and no resume ve
     { ...adapter, inbox: { ...adapter.inbox, events: neverProduces } },
     { close: async () => {} },
   )
-  const exit = await Effect.runPromise(
-    Effect.exit(
-      Effect.promise(() =>
-        runProgram(
-          { ...lazyEnv, COMMY_SUBSCRIBE: 'home' },
-          substrate,
-          {
-            loggerLayer: captureLogger([]),
-            readGitContext: () => Effect.succeed(NotInRepo()),
-          },
-          binderRef,
-        ),
-      ).pipe(Effect.timeoutFail({ duration: '5 seconds', onTimeout: () => 'boot hung' as const })),
-    ),
+  const exit = await Effect.runPromiseExit(
+    Effect.promise(() =>
+      runProgram(
+        { ...lazyEnv, COMMY_SUBSCRIBE: 'home' },
+        substrate,
+        {
+          loggerLayer: captureLogger([]),
+          readGitContext: () => Effect.succeed(NotInRepo()),
+        },
+        binderRef,
+      ),
+    ).pipe(Effect.timeoutFail({ duration: '5 seconds', onTimeout: () => 'boot hung' as const })),
   )
   expect(Exit.isSuccess(exit)).toBe(true)
 })
diff --git a/packages/mcp/server.ts b/packages/mcp/server.ts
index ce3c08b..f7c7274 100644
--- a/packages/mcp/server.ts
+++ b/packages/mcp/server.ts
@@ -456,7 +456,7 @@ export const makeProgram = (
                         Effect.map(Option.isNone),
                         // An unreadable store is treated as fresh, matching
                         // `resumeQueue`'s own best-effort degrade.
-                        Effect.catchAll(() => Effect.succeed(true)),
+                        Effect.orElseSucceed(() => true),
                         Effect.flatMap((nothingPersisted) =>
                           nothingPersisted
                             ? Deferred.succeed(resumeOutcome, false).pipe(Effect.asVoid)
@@ -524,10 +524,12 @@ export const makeProgram = (
       // Per-call project resolver. Operator override (COMMY_PROJECT)
       // is authoritative; otherwise derive from the calling session's cwd
       // at call time — process cwd is irrelevant.
-      const projectForCwd = (cwd: string | undefined): Effect.Effect<ProjectSlug | undefined> => {
-        if (parsed.project !== undefined) return Effect.succeed(parsed.project)
-        if (cwd === undefined) return Effect.succeed(undefined)
-        return Effect.map(deriveProject({ cwd, readGitContext }), Option.getOrUndefined)
+      const projectForCwd = (
+        cwd: string | undefined,
+      ): Effect.Effect<Option.Option<ProjectSlug>> => {
+        if (parsed.project !== undefined) return Effect.succeedSome(parsed.project)
+        if (cwd === undefined) return Effect.succeedNone
+        return deriveProject({ cwd, readGitContext })
       }
 
       // Sample the realm-wide editing switch once, before the tool list is
@@ -593,12 +595,10 @@ export const makeProgram = (
             Effect.succeedNone
       const rebuildNarrowSet: Effect.Effect<void> = (
         parsed.botName === undefined
-          ? Deferred.await(sessionIdDeferred).pipe(
-              Effect.map((sessionId): SessionId | undefined => sessionId),
-            )
-          : Effect.succeed(undefined)
+          ? Deferred.await(sessionIdDeferred).pipe(Effect.asSome)
+          : Effect.succeedNone
       ).pipe(
-        Effect.flatMap((sessionId) =>
+        Effect.flatMap((sessionId: Option.Option<SessionId>) =>
           withSessionContext(
             restoreSubscriptions({
               persisted: persistedTopicIntents,
@@ -606,7 +606,7 @@ export const makeProgram = (
               narrowSet,
               inbox: adapter.inbox,
             }),
-            { sessionId, project: parsed.project },
+            { sessionId: Option.getOrUndefined(sessionId), project: parsed.project },
           ),
         ),
         Effect.catchAll((err) =>
diff --git a/packages/mcp/subscription-restore.test.ts b/packages/mcp/subscription-restore.test.ts
index 48ecfd8..c6c18c8 100644
--- a/packages/mcp/subscription-restore.test.ts
+++ b/packages/mcp/subscription-restore.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, test } from 'bun:test'
 import { decodeChannelNameSync } from '@commy/core/ports'
-import { Effect, Option } from 'effect'
+import { Effect } from 'effect'
 import type { ProjectSlug } from './bootstrap.ts'
 import { createNarrowSet } from './narrow-set.ts'
 import type { SubscribeIntent } from './subscribe-parser.ts'
@@ -35,7 +35,7 @@ describe('seedDefaultsIfFresh', () => {
     await Effect.runPromise(
       seedDefaultsIfFresh(
         {
-          subscriptionStore: stubStore(() => Effect.succeed(Option.none())),
+          subscriptionStore: stubStore(() => Effect.succeedNone),
           registerDefaults: (project) =>
             Effect.sync(() => {
               defaultsCall = { project }
@@ -53,7 +53,7 @@ describe('seedDefaultsIfFresh', () => {
       seedDefaultsIfFresh(
         {
           subscriptionStore: stubStore(() =>
-            Effect.succeed(Option.some([newTopics('general'), channel('commy')])),
+            Effect.succeedSome([newTopics('general'), channel('commy')]),
           ),
           registerDefaults: () =>
             Effect.sync(() => {
@@ -71,7 +71,7 @@ describe('seedDefaultsIfFresh', () => {
     await Effect.runPromise(
       seedDefaultsIfFresh(
         {
-          subscriptionStore: stubStore(() => Effect.succeed(Option.some([]))),
+          subscriptionStore: stubStore(() => Effect.succeedSome([])),
           registerDefaults: () =>
             Effect.sync(() => {
               defaultsCalled = true
diff --git a/packages/mcp/subscription-store.ts b/packages/mcp/subscription-store.ts
index 76b1b5f..8a43fdd 100644
--- a/packages/mcp/subscription-store.ts
+++ b/packages/mcp/subscription-store.ts
@@ -178,7 +178,7 @@ const readSubscriptions = (
 > =>
   fs.readFileString(path).pipe(
     Effect.flatMap((raw) => decodeSubscriptionsFile(id, raw)),
-    Effect.map((intents) => Option.some(intents)),
+    Effect.asSome,
     Effect.catchIf(isNotFound, () => Effect.succeed(Option.none<ReadonlyArray<SubscribeIntent>>())),
   )
 
diff --git a/packages/mcp/tools-session.test.ts b/packages/mcp/tools-session.test.ts
index c03e649..4006977 100644
--- a/packages/mcp/tools-session.test.ts
+++ b/packages/mcp/tools-session.test.ts
@@ -26,7 +26,7 @@ interface SessionRig {
 
 const buildSessionRig = (
   options: {
-    readonly projectForCwd?: (cwd: string | undefined) => Effect.Effect<ProjectSlug | undefined>
+    readonly projectForCwd?: (cwd: string | undefined) => Effect.Effect<Option.Option<ProjectSlug>>
     readonly feedSessionId?: (sessionId: SessionId) => Effect.Effect<void>
   } = {},
 ): Effect.Effect<SessionRig, never, Scope.Scope> =>
@@ -430,11 +430,9 @@ test('post with session_id + cwd mints cc-<project>-<sid-prefix> derived from cw
       Effect.gen(function* () {
         const rig = yield* buildSessionRig({
           projectForCwd: (cwd) =>
-            Effect.succeed(
-              cwd === '/home/x/myproject'
-                ? Option.getOrUndefined(sanitiseProjectSlug('myproject'))
-                : undefined,
-            ),
+            cwd === '/home/x/myproject'
+              ? Effect.succeed(sanitiseProjectSlug('myproject'))
+              : Effect.succeedNone,
         })
         const result = yield* Effect.promise(() =>
           rig.client.callTool({
@@ -466,7 +464,8 @@ test('two sessions in different cwds mint two different project prefixes', () =>
           '/home/x/myproject-b': slug('myproject-b'),
         }
         const rig = yield* buildSessionRig({
-          projectForCwd: (cwd) => Effect.succeed(cwd === undefined ? undefined : cwdToSlug[cwd]),
+          projectForCwd: (cwd) =>
+            Effect.succeed(Option.fromNullable(cwd === undefined ? undefined : cwdToSlug[cwd])),
         })
         yield* Effect.promise(() =>
           rig.client.callTool({
@@ -503,9 +502,9 @@ test('post with cwd from a non-project directory falls back to bare cc-<8>', ()
   Effect.runPromise(
     Effect.scoped(
       Effect.gen(function* () {
-        // projectForCwd returns undefined when cwd is not in a known repo.
+        // projectForCwd returns none when cwd is not in a known repo.
         // The minted name must NOT inherit the plugin's own location.
-        const rig = yield* buildSessionRig({ projectForCwd: () => Effect.succeed(undefined) })
+        const rig = yield* buildSessionRig({ projectForCwd: () => Effect.succeedNone })
         yield* Effect.promise(() =>
           rig.client.callTool({
             name: 'post',
diff --git a/packages/mcp/tools.ts b/packages/mcp/tools.ts
index 96e3a5b..894589a 100644
--- a/packages/mcp/tools.ts
+++ b/packages/mcp/tools.ts
@@ -194,10 +194,10 @@ export interface RegisterToolsDeps {
    * minted `cc-<project>-<8>` name reflects the *calling* session's
    * project rather than the plugin's own location. Wired at boot in
    * `server.ts` from `COMMY_PROJECT` (operator override) and
-   * the git probe; defaults to a constant `undefined` resolver when
+   * the git probe; defaults to a resolver that always answers none when
    * omitted (tests that don't care about per-session derivation).
    */
-  readonly projectForCwd?: (cwd: string | undefined) => Effect.Effect<ProjectSlug | undefined>
+  readonly projectForCwd?: (cwd: string | undefined) => Effect.Effect<Option.Option<ProjectSlug>>
   /**
    * Restore (or seed) this session's narrow set on its first `subscribe`/
    * `unsubscribe` — memoised once per session_id in `server.ts`, so it runs
@@ -506,7 +506,7 @@ const UploadFileArgs = Schema.Struct({ path: Schema.String })
 
 const buildToolDefs = (deps: RegisterToolsDeps, cache: InternalCache): ReadonlyArray<ToolDef> => {
   const { adapter, identityCache, narrowSet } = deps
-  const projectForCwd = deps.projectForCwd ?? (() => Effect.succeed(undefined))
+  const projectForCwd = deps.projectForCwd ?? (() => Effect.succeedNone)
   /**
    * The tools that accept a host-supplied `session_id` (see
    * {@link ToolDef.hostSuppliedArgs}). EIGHT tools carry it. That is the same
@@ -548,7 +548,7 @@ const buildToolDefs = (deps: RegisterToolsDeps, cache: InternalCache): ReadonlyA
   }
   const projectForArgs = (
     args: Readonly<Record<string, unknown>>,
-  ): Effect.Effect<ProjectSlug | undefined> => projectForCwd(readCwd(args))
+  ): Effect.Effect<Option.Option<ProjectSlug>> => projectForCwd(readCwd(args))
   // Every tool call that carries arguments supplies its calling session's
   // context, uniformly. This DECIDES NOTHING about identity: it feeds the
   // shared session-id deferred (comms-k7cv) and puts the naming inputs where
@@ -569,7 +569,12 @@ const buildToolDefs = (deps: RegisterToolsDeps, cache: InternalCache): ReadonlyA
         projectForArgs(args).pipe(
           Effect.flatMap((project) =>
             feedSession(sessionId).pipe(
-              Effect.zipRight(withSessionContext(effect, { sessionId, project })),
+              Effect.zipRight(
+                withSessionContext(effect, {
+                  sessionId,
+                  project: Option.getOrUndefined(project),
+                }),
+              ),
             ),
           ),
         ),
@@ -937,7 +942,10 @@ const buildToolDefs = (deps: RegisterToolsDeps, cache: InternalCache): ReadonlyA
             // the snapshot persisted below captures the full live set and the
             // store's presence stays a true resume signal.
             if (sessionId !== undefined && deps.ensureSessionSubscriptions !== undefined) {
-              yield* deps.ensureSessionSubscriptions(sessionId, yield* projectForArgs(args))
+              yield* deps.ensureSessionSubscriptions(
+                sessionId,
+                Option.getOrUndefined(yield* projectForArgs(args)),
+              )
             }
             // Two sinks (see bootstrap.subscribeFromEnv): the consumer-side
             // narrow tells the event pump to tee matching events through;
@@ -983,7 +991,10 @@ const buildToolDefs = (deps: RegisterToolsDeps, cache: InternalCache): ReadonlyA
             // Fed by `runFor` before this effect runs (see subscribe).
             const sessionId = readSessionId(args)
             if (sessionId !== undefined && deps.ensureSessionSubscriptions !== undefined) {
-              yield* deps.ensureSessionSubscriptions(sessionId, yield* projectForArgs(args))
+              yield* deps.ensureSessionSubscriptions(
+                sessionId,
+                Option.getOrUndefined(yield* projectForArgs(args)),
+              )
             }
             yield* Effect.sync(() => narrowSet.remove(intent)).pipe(
               Effect.andThen(adapter.inbox.unsubscribe(intentToTarget(intent))),
diff --git a/packages/memory/adapter.test.ts b/packages/memory/adapter.test.ts
index d32c8e9..73a451d 100644
--- a/packages/memory/adapter.test.ts
+++ b/packages/memory/adapter.test.ts
@@ -140,10 +140,9 @@ test('concurrent acquire on a fresh adapter binds exactly one name', async () =>
   const adapter = await Effect.runPromise(memoryAdapter())
   const names = ['agent-a', 'agent-b', 'agent-c', 'agent-d'].map((n) => decodeBotNameSync(n))
   const exits = await Effect.runPromise(
-    Effect.all(
-      names.map((name) => Effect.exit(adapter.identity.acquire(name))),
-      { concurrency: 'unbounded' },
-    ),
+    Effect.forEach(names, (name) => Effect.exit(adapter.identity.acquire(name)), {
+      concurrency: 'unbounded',
+    }),
   )
   const successes = exits.filter(Exit.isSuccess)
   expect(successes).toHaveLength(1)
diff --git a/packages/testing/contract.ts b/packages/testing/contract.ts
index 1575d15..4323069 100644
--- a/packages/testing/contract.ts
+++ b/packages/testing/contract.ts
@@ -152,11 +152,7 @@ const takeUntil = (
   queue: Queue.Queue<InboundEvent>,
   predicate: (event: InboundEvent) => boolean,
 ): Effect.Effect<InboundEvent> =>
-  Queue.take(queue).pipe(
-    Effect.flatMap((event) =>
-      predicate(event) ? Effect.succeed(event) : takeUntil(queue, predicate),
-    ),
-  )
+  Queue.take(queue).pipe(Effect.filterOrElse(predicate, () => takeUntil(queue, predicate)))
 
 /**
  * Await the first event matching `predicate`, failing the test (with
diff --git a/packages/zulip/adapter-events.test.ts b/packages/zulip/adapter-events.test.ts
index e08e3c2..1429553 100644
--- a/packages/zulip/adapter-events.test.ts
+++ b/packages/zulip/adapter-events.test.ts
@@ -47,7 +47,7 @@ import { HttpClient } from '@effect/platform'
 import {
   Duration,
   Effect,
-  Option,
+  type Option,
   Queue,
   Redacted,
   type Scope,
@@ -493,7 +493,7 @@ effectTest(
     Effect.gen(function* () {
       const stub = yield* makeStubHttpClient
       const adapter = yield* buildAdapterWithQueueConfig(stub, {
-        resumeQueue: () => Effect.succeed(Option.some({ queueId: 'resumed-q', lastEventId: 41 })),
+        resumeQueue: () => Effect.succeedSome({ queueId: 'resumed-q', lastEventId: 41 }),
       })
       // The backlog buffered while the seat was dead: the reacted-to message
       // (which seeds the ref cache in-batch) followed by the reaction on it.
@@ -569,7 +569,7 @@ effectTest(
       const stub = yield* makeStubHttpClient
       const outcomes: boolean[] = []
       const adapter = yield* buildAdapterWithQueueConfig(stub, {
-        resumeQueue: () => Effect.succeed(Option.some({ queueId: 'resumed-q', lastEventId: 41 })),
+        resumeQueue: () => Effect.succeedSome({ queueId: 'resumed-q', lastEventId: 41 }),
         onResumeOutcome: (replayed) => Effect.sync(() => void outcomes.push(replayed)),
       })
       yield* stub.respondSequence('GET', '/api/v1/events', [
@@ -594,7 +594,7 @@ effectTest(
       const stub = yield* makeStubHttpClient
       const outcomes: boolean[] = []
       const adapter = yield* buildAdapterWithQueueConfig(stub, {
-        resumeQueue: () => Effect.succeed(Option.some({ queueId: 'dead-q', lastEventId: 41 })),
+        resumeQueue: () => Effect.succeedSome({ queueId: 'dead-q', lastEventId: 41 }),
         onResumeOutcome: (replayed) => Effect.sync(() => void outcomes.push(replayed)),
       })
       // Fresh register for the re-registration after the dead resume-poll.
diff --git a/packages/zulip/adapter.ts b/packages/zulip/adapter.ts
index 4b80c41..4f595c5 100644
--- a/packages/zulip/adapter.ts
+++ b/packages/zulip/adapter.ts
@@ -1161,7 +1161,7 @@ export const zulipAdapter = (
             Arr.findFirst(res.members, (u) => u.is_active && u.full_name === name).pipe(
               Option.match({
                 onNone: () => Effect.succeed(Option.none<Identity>()),
-                onSome: (match) => toIdentity(match).pipe(Effect.map(Option.some)),
+                onSome: (match) => toIdentity(match).pipe(Effect.asSome),
               }),
             ),
           ),
@@ -1339,7 +1339,10 @@ export const zulipAdapter = (
             onSome: Effect.succeed,
           }),
         ),
-        Effect.flatMap((map) => (map.has(name) ? Effect.succeed(map) : refreshKnownStreams())),
+        Effect.filterOrElse(
+          (map) => map.has(name),
+          () => refreshKnownStreams(),
+        ),
         Effect.map((map) => Option.fromNullable(map.get(name))),
       )
 
@@ -1369,7 +1372,7 @@ export const zulipAdapter = (
         Effect.flatMap((res) =>
           Option.match(fromWireDescription(res.stream.description), {
             onNone: () => Effect.succeed(Option.none<ChannelDescription>()),
-            onSome: (raw) => decodeChannelDescription(raw).pipe(Effect.map(Option.some)),
+            onSome: (raw) => decodeChannelDescription(raw).pipe(Effect.asSome),
           }),
         ),
       )
@@ -1470,7 +1473,7 @@ export const zulipAdapter = (
             Arr.last(res.messages).pipe(
               Option.match({
                 onNone: () => Effect.succeed(Option.none<MessageId>()),
-                onSome: (m) => decodeMessageId(String(m.id)).pipe(Effect.map(Option.some)),
+                onSome: (m) => decodeMessageId(String(m.id)).pipe(Effect.asSome),
               }),
             ),
           ),
@@ -2126,10 +2129,9 @@ export const zulipAdapter = (
             { operator: 'topic', operand: topic },
           ])
         return readTopic(threadName).pipe(
-          Effect.flatMap((messages) =>
-            messages.length > 0
-              ? Effect.succeed(messages)
-              : readTopic(applyResolvedPrefix(threadName, true)),
+          Effect.filterOrElse(
+            (messages) => messages.length > 0,
+            () => readTopic(applyResolvedPrefix(threadName, true)),
           ),
           Effect.mapError((cause) => new HistoryError({ operation: 'readThread', cause })),
         )
diff --git a/packages/zulip/events.test.ts b/packages/zulip/events.test.ts
index 2255573..7e5aa08 100644
--- a/packages/zulip/events.test.ts
+++ b/packages/zulip/events.test.ts
@@ -1958,7 +1958,7 @@ test(
             },
           }),
           resolveDirectory: () => Effect.succeed(directoryFor(HERMES, MAINTAINER)),
-          currentRegistration: Effect.succeed(Option.some({ queueId: 'q-stale', lastEventId: 0 })),
+          currentRegistration: Effect.succeedSome({ queueId: 'q-stale', lastEventId: 0 }),
           boundIdentity: HERMES,
           messageRefCache: createMessageRefCache(),
         }
diff --git a/packages/zulip/events.ts b/packages/zulip/events.ts
index d1ab703..4a26ea5 100644
--- a/packages/zulip/events.ts
+++ b/packages/zulip/events.ts
@@ -586,8 +586,8 @@ export const fetchMessageRef = (
     .pipe(
       Effect.flatMap((res) => {
         const message = res.messages[0]
-        if (message === undefined || message.id !== messageId) return Effect.succeed(Option.none())
-        return decodeMessageRef(message, base).pipe(Effect.map(Option.some))
+        if (message === undefined || message.id !== messageId) return Effect.succeedNone
+        return decodeMessageRef(message, base).pipe(Effect.asSome)
       }),
     )
 
diff --git a/packages/zulip/http.ts b/packages/zulip/http.ts
index b988695..3bc5f6b 100644
--- a/packages/zulip/http.ts
+++ b/packages/zulip/http.ts
@@ -372,8 +372,10 @@ export const makeZulipHttp = (
             Effect.flatMap((text) => classifyEnvelope(text, response.status, url)),
           ),
         ),
-        Effect.catchTag('RequestError', (cause) => Effect.fail(transportError(url, cause))),
-        Effect.catchTag('ResponseError', (cause) => Effect.fail(transportError(url, cause))),
+        Effect.catchTags({
+          RequestError: (cause) => Effect.fail(transportError(url, cause)),
+          ResponseError: (cause) => Effect.fail(transportError(url, cause)),
+        }),
       )
 
     const sendWithRetry = (
@@ -465,10 +467,10 @@ export const makeZulipHttp = (
                     Effect.mapError((cause) => transportError(url, cause)),
                   )
                 }),
-                Effect.catchTag('RequestError', (cause) => Effect.fail(transportError(url, cause))),
-                Effect.catchTag('ResponseError', (cause) =>
-                  Effect.fail(transportError(url, cause)),
-                ),
+                Effect.catchTags({
+                  RequestError: (cause) => Effect.fail(transportError(url, cause)),
+                  ResponseError: (cause) => Effect.fail(transportError(url, cause)),
+                }),
               )
             })()
           : Effect.die(