refactor(db): Prisma → Drizzle — the fleet has one ORM

[catomean]

Stack-uniformity migration (George, 2026-09-01: "Drizzle everywhere" for fleet-owned Postgres apps). Follows the recipe proven in bitbaum/biaslens#26 — solon is the first follow-up repo with a live database (real governance data: 1 org, 2 votes, 1 proposal — nothing here may touch it).

Call sites (before → after)

solon's Prisma surface was ~10× biaslens's: 37 files imported @prisma/client or called prisma.*. All rewritten, now zero:

Layer	Files	What changed
Client	src/lib/db.ts → src/lib/db/client.ts	PrismaClient + @prisma/adapter-pg singleton → lazy drizzle(new Pool(...)) proxy (hirnli house pattern; build/CI stays hermetic)
Schema/types	src/lib/db/schema.ts (new)	9 tables, 12 pg enums, full relations(), $inferSelect row types
Enum vocabulary	src/lib/db/enums.ts (new)	dependency-free const objects with Prisma-identical semantics (MemberType.HUMAN === "HUMAN"); z.enum(DecisionCategory) keeps working. methods/prisma-enum.ts renamed db-enum.ts
Domain	voting, proposals, membership, decision, treasury, org, recognition, tally	findUnique/include → db.query.*.findFirst/with, $transaction → db.transaction, upsert → onConflictDoUpdate, count() → select({count()})/$count, Prisma.Decimal → numeric-as-string (Number() at the same call sites that already did it), Prisma.JsonValue/InputJsonValue/DbNull → unknown/null
API routes	8 routes	same shapes; relation-filtered wheres became inArray(col, subquery); repeated org-by-slug lookup extracted to orgBySlug() in domain/org.ts (DRY — 4 routes used it)
Pages/components	8 server components	same query semantics, ?? null where Prisma returned null and Drizzle returns undefined
Scripts	add-member, add-treasury-source	rewritten; $disconnect() → db.$client.end()
Tests	3 integration specs + 3 unit specs	fixtures on db.insert(...).returning(); enum imports repointed

grep -rni prisma now hits only the lockfile (drizzle-orm's own optional peers), the schema's provenance comments, and AGENTS.md's history note.

Schema parity — proven, not asserted

src/lib/db/schema.ts matches the tables Prisma's migrations created, byte-for-byte: table/column names, TIMESTAMP(3), NUMERIC(10,2)/(12,2), VARCHAR(90), PascalCase enum type names ("MemberType"), Prisma's index/constraint names (organizations_slug_key, members_organization_id_fkey, …), cascade rules, and client-side uuid minting ($defaultFn(randomUUID) — the columns carry no DB default, exactly like @default(uuid())).

Evidence 1 (replay): scratch Postgres 16 — Prisma's 0_init + 1_seed_org1 + 2_voting_methods into db A, drizzle-kit migrate (0000_init + 0001_seed_org1) into db B, normalized pg_dump --schema-only diff: 50/50 statements identical. Only spelling differences normalized away: CURRENT_TIMESTAMP vs now() (same Postgres function) and column order (Prisma's ALTERs appended columns; irrelevant on the live DB, which 0000 never touches). Seed data equal in both (orangecat org, allocation_policy v1, 2 genesis audit events).

Evidence 2 (production): pg_dump --schema-only of the live solon database vs the drizzle-built scratch DB: identical — the only extra statement on prod is COMMENT ON SCHEMA public IS ''.

Evidence 3 (behavior): all 3 integration specs (vote spine, dot allocation, founding seat — 10 tests) green against the drizzle-built scratch DB, plus an HTTP smoke of the built standalone server: GET /api/orgs/orangecat returns the seeded org, audit 200, missing org 404.

Live-DB cutover mechanism (why the deploy is a no-op)

Deploys run fleetcrown/scripts/hetzner/apply-schema.sh, which for drizzle-layout apps applies only migrations not yet recorded in the app's public._deploy_schema_history ledger — and refuses to auto-baseline a populated database. So before this PR merges, the ledger on bitbaum was seeded by hand (after proving prod schema ≡ drizzle schema, Evidence 2):

CREATE TABLE IF NOT EXISTS public._deploy_schema_history (tag text PRIMARY KEY, applied_at timestamptz NOT NULL DEFAULT now());
INSERT INTO public._deploy_schema_history(tag) VALUES ('0000_init'), ('0001_seed_org1') ON CONFLICT DO NOTHING;

✅ already applied on the box (solon database). The deploy's schema step therefore finds both tags recorded, applies nothing, and ships code only. _prisma_migrations is intentionally left in place until this deploy is verified live (a rollback deploy of a Prisma-era release would still need it); it gets dropped right after verification.

Recipe deltas vs biaslens

• Live DB: biaslens had no deploy pipeline; solon's cutover is the ledger baseline above (the step biaslens#26 predicted the follow-ups would need — mechanism differs from the predicted drizzle.__drizzle_migrations insert because prod is applied by apply-schema.sh, not drizzle-kit migrate; drizzle's own journal only matters for fresh DBs, i.e. CI).
• Seed as migration: solon ships reference data in its migration chain; ported verbatim as custom migration 0001_seed_org1 so CI's fresh-DB replay stays "baseline + seed", same as before.
• Enums as values: biaslens had none; solon imports 12 enums as runtime values in 20+ files, so they live in a dependency-free enums.ts the pgEnums are built from (one SSOT, no drift possible, client-bundle safe).
• snake_case: solon's schema was fully @mapped — no PascalCase table/column quoting needed (only enum type names keep PascalCase).
• Decimal columns: biaslens had none; solon keeps drizzle's string mode and converts with the Number() calls the code already had.
• prisma.config.ts (Prisma 7 driver-adapter era) deleted alongside the classic artifacts; CI's two prisma generate steps and the prisma migrate deploy replay became zero codegen + drizzle-kit migrate; drizzle/meta added to .prettierignore (generated, drizzle-kit owns it).

Verification

npm run verify (prettier + eslint + tsc + design:check + 82 unit tests) and npm run build green. Integration: 10/10 against a fresh drizzle-migrated Postgres. Live smoke via standalone build. Dependabot PRs #129/#132 (@prisma/*) become obsolete and will be closed on merge.

🤖 Generated with Claude Code

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