What vibe.0 is
vibe.0 is the host cell. It is a 2015 vibe.d fork (DUB name vibe-0, git tag v1.2.1) with libasync as the only event backend, botan (and optionally OpenSSL) for TLS, and libhttp2 for HTTP/2. svelte-d does not wrap it in Node. +page.server.d, +server.d, +layout.server.d, and hooks.server.d print as vibe.0 D and registerWebInterface onto the engine’s webserver. If you have just finished Getting Started and opened svelte-engine-ws/webserver in VS Code with code-d, the identifiers that complete under import vibe.http.server; and import helpers; are the subject of this section.
It is not official vibe.d. Diet / vibe.templ are gone. vibe.web.rest is gone. Mongo is gone. The libevent / Win32 / libev drivers are gone. vibeVersionString is still "0.7.23" — the upstream tag at the fork — and the Server / User-Agent headers still say vibe.d/0.7.23 unless the app sets serverString. Do not conflate that string with the git tag.
The consumer shape is construction: VibeCustomMain, your own main(), listenHTTP, runEventLoop(). Default appmain.d static asserts otherwise. vibe.core.core starts the only backend, LibasyncDriver. One fiber per TCP connection owns HTTP/1.1 keep-alive or an HTTP/2 session. Dispatch is context.requestHandler → URLRouter.handleRequest. registerWebInterface turns public methods + @path @method @before @after into router.match entries.
import vibe.d; and import vibe.vibe; are the same public re-export list. Neither gives you a working main() in this fork. Typical host files import narrower modules (vibe.http.server, vibe.data.json, vibe.web.web) plus the engine barrel import helpers;. They do not import libwasm. A +page.server.d that does is in the wrong cell.
Barrel vs explicit imports
In vibe.d / vibe.vibe: core (args, concurrency, core, file, log, net, sync, trace), crypto.passwordhash, data.json (which public-imports serialization), db.redis.redis, HTTP (auth.basic_auth, client, fileserver, form, proxy, router, server, debugger, websockets), inet (message, url, urltransfer), mail.smtp, streams (counting, memory, operations, ssl, zlib), textfilter, utils.string, web.web, plus Phobos toDelegate / to / std.datetime / enforce.
Public but not starred — import them by name, which is what the engine and the README samples do:
| Area | Modules |
|---|---|
| HTTP | http.common, http.status, http.session, http.http2, http.cookiejar, http.log, http.auth.digest_auth |
| Stream | stream.tls (prefer over ssl), stream.botan, stream.openssl, stream.brotli |
| Data | data.xml, data.dom, data.brotli |
| DB | db.sqlite.sqlite3, db.pgsql.pgsql, db.redis.idioms, db.redis.sessionstore, db.redis.types |
| Other | crypto.cryptorand, inet.path, inet.mimetypes, inet.webform, web.common, web.validation |
vibe.core.drivers.* and vibe.internal.* (except meta.funcattr, which registerWebInterface public-imports as @before / @after) are not a stable API.
How svelte-d hangs a kit on this
svelte-d host is dub build in ws/webserver with the same LDC 1.43 as wasm and with DFLAGS / DC cleared. Generated classes are dest-unique (AdminPageServer, UsersPageServer) so every ingested route can hang on webserver/source/app.d without colliding. assembleHostRoutes writes between // svelte-d:begin-host-routes markers. registerWebInterface is called under /__svelte-d/host/; Vite keeps /. Adapters copy the host exe and public/; they do not add a Node HTTP stack.
The rest of this section is the runtime in the order you will meet it when you open a printed +page.server.d. Custom main & event loop is process start. HTTP is the connection and the request object. URLRouter is the match language. registerWebInterface is how a class becomes routes. JSON, sessions, databases is the data plane. lang=“d” on the host cell puts the same identifiers back next to the file you actually write.
svelte-d’s vibe.0 host files page is the author-facing contract. This section is the library that contract names.