# okhttp 5.5.0 — parent-5.5.0

- Product: okhttp (https://whatsnew.fyi/product/okhttp)
- Vendor: lysine-dev
- Date: 2026-08-16
- Version: 5.5.0
- Original notes: https://github.com/lysine-dev/okhttp/releases/tag/parent-5.5.0
- Permalink: https://whatsnew.fyi/product/okhttp/releases/5.5.0
- Labels: Machine-generated from commit messages — the vendor published no release notes

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Dns2, the new OkHttp DNS API with support for DNS message reading and writing, HTTPS DNS records, and Dns.lookup on DnsOverHttps.
- **added** — ECH (Encrypted Client Hello) support including service metadata in Route, configureTlsExtensions API integration, Android ECH support, and EchAwareDns.
- **added** — RFC 1008 (QUERY Method) support.
- **added** — CachingTransport for DNS caching with in-memory caching in DnsOverHttps and AndroidDns, public DnsCache API, and cache eviction.
- **added** — FakeNetwork for testing that allows completely faking out the network and TLS.
- **fixed** — Don't crash route selection when the system proxy selector throws.
- **fixed** — Reject malformed DNS messages that have infinite loops.
- **fixed** — read HTTPS mandatory SvcParamKeys as 16-bit values and read DNS RDLENGTH as an unsigned 16-bit value.
- **fixed** — Flush HTTP/1 request bodies before detachTimeout and handle unsupported AliasMode records, ECH Retry, and conscrypt provider changes.
- **changed** — Update to Okio 3.18 and support Kotlin Multiplatform in applyJavaModules.