How to Fix BlueSky Custom Feed Timeout Errors

BlueSky custom feeds are powerful because they let independent feed generator services choose which post URIs should appear in a topic timeline. That flexibility also creates a failure mode: if the feed service is slow, unavailable, or returns a bad skeleton response, the user sees a loading failure instead of a feed.

A timeout is usually not a content problem. It is an infrastructure and response-shape problem. The AppView asks the external feed generator for a list of post URIs, then the AppView hydrates those URIs into full post views. If that handoff is slow or malformed, the feed can appear broken even when the indexed posts still exist.

How custom feed requests work

The official BlueSky custom feeds guide explains that a feed generator service receives requests and returns post URIs with optional metadata. The getFeedSkeleton Lexicon requires a feed AT URI parameter, supports cursor pagination, and returns a feed array of skeleton feed posts.

The user requests a custom feed from the AppView.

The AppView resolves the feed generator declaration and service DID.

The AppView calls the feed generator service endpoint.

The feed generator returns a skeleton response with post AT URIs.

The AppView hydrates those post URIs into full post views for the client.

Common causes of feed timeout or 504 errors

A 504-style failure usually means an upstream service did not return in time. In custom-feed terms, that can happen when the feed generator performs expensive ranking work during the request, waits on a cold database, calls another API synchronously, or returns a response that forces retry behavior.

The feed server is cold-starting and cannot answer quickly.

Ranking queries scan too much data instead of using precomputed indexes.

The server calls LLMs, external APIs, or remote databases inside the live getFeedSkeleton request.

Pagination cursors are not stable, causing repeated or empty fetches.

The response exceeds expected shape, includes invalid post URIs, or omits the required feed array.

The HTTPS endpoint, DNS, certificate, or DID document service URL is misconfigured.

Fix the response path first

The fastest fix is to make getFeedSkeleton boring. The request should read precomputed post URIs, apply a small ranking or filter pass, return a stable cursor, and exit. Heavy indexing should happen continuously from the firehose or a background worker, not when the AppView is waiting for a feed skeleton.

Use the BlueSky feed skeleton generator helper to check payload shape, URI formatting, cursor length, reqId length, and reason metadata before debugging deeper infrastructure.

When the response path looks correct but requests fail with 401 or proxy auth errors, start by resolving service authentication mismatches and proxy authorization anomalies inside custom feed generator instances before changing ranking logic.

Check the infrastructure layer

A correct JSON response can still fail if the feed generator host is unreliable. Confirm that the feed endpoint is available over HTTPS, the service path is reachable from outside your network, the server avoids cold starts, and the database has indexes for the exact feed query.

Keep a health endpoint warm.

Precompute feed candidates ahead of the request.

Use stable cursor values that combine time and CID or another unique sortable key.

Cap result limits at the Lexicon maximum of 100.

Return only post AT URIs and supported optional metadata.

Log request IDs, response times, empty results, invalid URIs, and upstream dependency failures.

Do not depend only on third-party feeds for discovery

Custom feeds are useful, but they are not the only discovery path. If a feed generator times out or changes ranking logic, your brand still needs clear public posts that are understandable through search, profile browsing, lists, starter packs, and AI answer engines.

That is where ONYX fits. A consistent queue with text-intent keywords, natural AI Voice drafts, readable threads, and a content calendar gives feed operators better post candidates while reducing your dependence on any single third-party feed server.

A reliable ONYX-backed workflow

Plan weekly topics in the content calendar instead of chasing feed ranking changes.

Use recurring language around your real niche so feeds and search can classify the account.

Split complex ideas into threads with clear post URIs and topic terms.

Use list and feed tools for validation, but keep core posting consistent even when feed servers are slow.

Measure whether followers and replies grow from the posting rhythm, not only from one custom feed.

Use ONYX to build a feed-friendly BlueSky posting rhythm with approved posts that keep working even when external feed servers are unreliable.