Merge pull request #20 from PolicyEngine/feat/modal-economy-sims

feat: Remove worker, add Modal auth to Cloud Run

Author: nikhilwoodruff

.env.example

@@ -21,6 +21,6 @@ LOGFIRE_TOKEN=your-logfire-token-here
 LOGFIRE_ENVIRONMENT=local
 
 # Modal.com (compute backend)
-# Authentication is via `modal token set` command, not env vars
-# Modal functions need a secret called "policyengine-db" with:
-#   DATABASE_URL, SUPABASE_URL, SUPABASE_KEY, STORAGE_BUCKET
+# Get tokens from modal.com dashboard or via `modal token new`
+MODAL_TOKEN_ID=ak-...
+MODAL_TOKEN_SECRET=as-...

.github/workflows/deploy.yml

@@ -85,6 +85,8 @@ jobs:
           TF_VAR_supabase_db_url: ${{ secrets.SUPABASE_DB_URL }}
           TF_VAR_logfire_token: ${{ secrets.LOGFIRE_TOKEN }}
           TF_VAR_logfire_environment: prod
+          TF_VAR_modal_token_id: ${{ secrets.MODAL_TOKEN_ID }}
+          TF_VAR_modal_token_secret: ${{ secrets.MODAL_TOKEN_SECRET }}
         run: terraform apply -auto-approve
 
       - name: Deploy API to Cloud Run
@@ -93,12 +95,6 @@ jobs:
             --region=${{ vars.GCP_REGION }} \
             --image=$IMAGE_URL:${{ github.sha }}
 
-      - name: Deploy worker to Cloud Run
-        run: |
-          gcloud run services update ${{ vars.WORKER_SERVICE_NAME }} \
-            --region=${{ vars.GCP_REGION }} \
-            --image=$IMAGE_URL:${{ github.sha }}
-
       - name: Get API URL
         run: |
           API_URL=$(gcloud run services describe ${{ vars.API_SERVICE_NAME }} \

CLAUDE.md

@@ -15,11 +15,12 @@ FastAPI backend for tax-benefit policy microsimulations using PolicyEngine's UK
 
 ```bash
 make install          # install dependencies with uv
-make dev              # start supabase + api + worker via docker compose
+make dev              # start supabase + api via docker compose
 make test             # run unit tests
 make integration-test # full integration tests
 make format           # ruff formatting
 make lint             # ruff linting with auto-fix
+make modal-deploy     # deploy Modal.com serverless functions
 ```
 
 Local development uses docker compose with a local Supabase instance. Copy `.env.example` to `.env` for local config.
@@ -29,7 +30,7 @@ Local development uses docker compose with a local Supabase instance. Copy `.env
 - `src/policyengine_api/api/` - FastAPI routers (14 endpoint groups)
 - `src/policyengine_api/models/` - SQLModel database models
 - `src/policyengine_api/services/` - database and storage services
-- `src/policyengine_api/tasks/` - background worker for async simulations
+- `src/policyengine_api/modal_app.py` - Modal.com serverless functions
 - `supabase/migrations/` - SQL migrations for RLS and Postgres features
 - `terraform/` - GCP Cloud Run infrastructure
 - `docs/` - Next.js documentation site
@@ -38,7 +39,7 @@ Local development uses docker compose with a local Supabase instance. Copy `.env
 
 SQLModel defines all database schemas. Use Pydantic BaseModel for request/response schemas and BaseSettings for configuration. All API endpoints should be async functions.
 
-The background worker processes simulations asynchronously. Clients poll simulation status until complete.
+Modal.com serverless functions handle compute-intensive simulations with sub-1s cold starts. Clients poll simulation status until complete.
 
 MCP server exposes all endpoints as Claude tools via streamable HTTP transport.
 

Dockerfile

@@ -1,10 +1,10 @@
 # Build docs
-FROM node:22-slim AS docs-builder
+FROM oven/bun:1 AS docs-builder
 WORKDIR /docs
 COPY docs/package.json docs/bun.lock ./
-RUN npm install
+RUN bun install
 COPY docs/ ./
-RUN npm run build
+RUN bun run build
 
 # Build API
 FROM ghcr.io/astral-sh/uv:python3.13-bookworm-slim

Makefile

@@ -120,6 +120,7 @@ modal-deploy:
 		"DATABASE_URL=$$SUPABASE_POOLER_URL" \
 		"SUPABASE_URL=$$SUPABASE_URL" \
 		"SUPABASE_KEY=$$SUPABASE_KEY" \
+		"STORAGE_BUCKET=$$STORAGE_BUCKET" \
 		--force
 	uv run modal deploy src/policyengine_api/modal_app.py
 

README.md

@@ -6,7 +6,7 @@ FastAPI service for PolicyEngine microsimulations with Supabase backend and obje
 
 - RESTful API for tax-benefit microsimulations
 - Supabase for PostgreSQL database and object storage
-- Background worker for simulation processing
+- Modal.com serverless compute with sub-1s cold starts
 - SQLModel for type-safe database models
 - Logfire observability and monitoring
 - Terraform deployment to GCP Cloud Run
@@ -171,7 +171,7 @@ This drops all tables, deletes the storage bucket, then recreates tables from SQ
 - **API server**: FastAPI application (port 8000)
 - **Database**: Supabase PostgreSQL
 - **Storage**: Supabase object storage for .h5 dataset files
-- **Worker**: Polling worker for background simulations
+- **Compute**: Modal.com serverless functions for simulations
 
 ### Data models
 
@@ -195,7 +195,7 @@ policyengine-api-v2/
 │   ├── config/           # Settings
 │   ├── models/           # SQLModel database models
 │   ├── services/         # Database, storage
-│   ├── tasks/            # Background worker
+│   ├── modal_app.py      # Modal.com serverless functions
 │   └── main.py           # FastAPI app
 ├── supabase/
 │   └── migrations/       # RLS policies and storage

docs/README.md

@@ -5,12 +5,6 @@ This is a [Next.js](https://nextjs.org) project bootstrapped with [`create-next-
 First, run the development server:
 
 ```bash
-npm run dev
-# or
-yarn dev
-# or
-pnpm dev
-# or
 bun dev
 ```
 

terraform/main.tf

@@ -106,76 +106,13 @@ resource "google_cloud_run_v2_service" "api" {
         name  = "DEBUG"
         value = "false"
       }
-    }
-  }
-
-  depends_on = [google_project_service.required_apis]
-
-  lifecycle {
-    ignore_changes = [template[0].containers[0].image]
-  }
-}
-
-# Cloud Run service for worker (always-on, polls for pending work)
-resource "google_cloud_run_v2_service" "worker" {
-  name     = "${var.project_name}-worker"
-  location = var.region
-  ingress  = "INGRESS_TRAFFIC_INTERNAL_ONLY"
-
-  template {
-    service_account = google_service_account.cloudrun.email
-
-    scaling {
-      min_instance_count = 1
-      max_instance_count = 1
-    }
-
-    containers {
-      image   = "${var.region}-docker.pkg.dev/${var.project_id}/${google_artifact_registry_repository.repo.repository_id}/${var.project_name}:latest"
-      command = ["python", "-m", "policyengine_api.tasks.worker"]
-
-      resources {
-        limits = {
-          cpu    = var.worker_cpu
-          memory = var.worker_memory
-        }
-      }
-
-      ports {
-        container_port = 8080
-      }
-
-      env {
-        name  = "SUPABASE_URL"
-        value = var.supabase_url
-      }
-      env {
-        name  = "SUPABASE_KEY"
-        value = var.supabase_key
-      }
-      env {
-        name  = "SUPABASE_DB_URL"
-        value = var.supabase_db_url
-      }
-      env {
-        name  = "LOGFIRE_TOKEN"
-        value = var.logfire_token
-      }
-      env {
-        name  = "LOGFIRE_ENVIRONMENT"
-        value = var.logfire_environment
-      }
-      env {
-        name  = "STORAGE_BUCKET"
-        value = var.storage_bucket
-      }
       env {
-        name  = "WORKER_POLL_INTERVAL"
-        value = "10"
+        name  = "MODAL_TOKEN_ID"
+        value = var.modal_token_id
       }
       env {
-        name  = "WORKER_PORT"
-        value = "8080"
+        name  = "MODAL_TOKEN_SECRET"
+        value = var.modal_token_secret
       }
     }
   }

terraform/outputs.tf

@@ -8,11 +8,6 @@ output "api_url" {
   value       = google_cloud_run_v2_service.api.uri
 }
 
-output "worker_service_name" {
-  description = "Worker service name"
-  value       = google_cloud_run_v2_service.worker.name
-}
-
 output "api_service_name" {
   description = "API service name"
   value       = google_cloud_run_v2_service.api.name

terraform/variables.tf

@@ -76,26 +76,14 @@ variable "api_max_instances" {
   default     = 10
 }
 
-variable "worker_cpu" {
-  description = "CPU for worker service"
+variable "modal_token_id" {
+  description = "Modal.com token ID for serverless compute"
   type        = string
-  default     = "2"
+  sensitive   = true
 }
 
-variable "worker_memory" {
-  description = "Memory for worker service"
+variable "modal_token_secret" {
+  description = "Modal.com token secret for serverless compute"
   type        = string
-  default     = "2Gi"
-}
-
-variable "worker_min_instances" {
-  description = "Minimum number of worker instances"
-  type        = number
-  default     = 1
-}
-
-variable "worker_max_instances" {
-  description = "Maximum number of worker instances"
-  type        = number
-  default     = 5
+  sensitive   = true
 }