October 24, 2025

Serverless ClickHouse migrations with moose migrate

Run schema diffs and applies straight against a ClickHouse endpoint—perfect for OLAP-only or CI/CD environments that don't boot the full Moose runtime.

# Detect changes and persist the migration plan
moose generate migration \
  --clickhouse-url "https://user:pass@ch.serverless.dev/main" \
  --save
 
# Apply the plan directly to ClickHouse
moose migrate --clickhouse-url "https://user:pass@ch.serverless.dev/main"

PR: (#2872) | Docs: Serverless ClickHouse migrations guide

Adaptive JSON columns with ClickHouseJson

Model semi-structured payloads while locking in typed paths for the fields you care about.

import { Key, ClickHouseJson, Int64 } from "@514labs/moose-lib"; interface UserMetadata {  userId: string;  sessionId: string;} export interface UserActivity {  id: Key<string>;  // ClickHouseJson<maxDynamicPaths, maxDynamicTypes, skipPaths, skipRegexes>  metadata: UserMetadata & ClickHouseJson<256, 16, ["internal.debug"], ["^tmp\\."]>;}

PR:(#2887) | Docs: Data modeling

Moose

• moose migrate --clickhouse-url – Generate and apply migrations directly against hosted ClickHouse, ideal for OLAP-only or CI/CD workflows that run without the full Moose runtime. Docs: Serverless ClickHouse migrations | PRs #2872.
• LLM-friendly docs & endpoints – Framework pages expose TS/Py "LLM view" links and the CLI now serves /llm-ts.txt + /llm-py.txt for assistants that need scoped context. Docs: LLM docs | PRs #2892.
• Flexible JSON columns – ClickHouseJson lets models cap dynamic paths, pin typed paths, or skip keys/regexes so ingestion can accept evolving payloads without breaking typed reads. Docs: Data modeling | PRs #2887.
• Configurable source_dir – moose.config.toml can point at src/ (or any folder) instead of the default app/, simplifying adoption inside existing repos. Docs: Configuration | PRs #2886.
• Array transforms can fan out events – Transform functions that return arrays automatically emit one Kafka message per element, covering explode/normalize patterns without extra producers. Docs: Transform functions | PRs #2882.
• ClickHouse modeling controls – Table DSL now covers TTL per table/column, sampleByExpression, and fully configurable secondary indexes (type, args, granularity) so you can encode retention + performance plans directly in code. Docs: TTL | | | PRs , , .

Boreal

• Navigation slug fix – Visiting a 404 no longer strips the org ID from subsequent links, so multi-tenant operators stay on the right workspace. (commercial#1014)