SMC

Show Me your Code (SMC)

An Online Code Test platform: interviewees take coding tests in the browser, and hiring managers create tests, manage candidates, and review results.

Quick start

You need backend/.env first

make smc-up      # build + start postgres → backend → frontend
make ps          # confirm containers are healthy
make healthz     # probe http://localhost:8080/api/healthz

Frontend at http://localhost:8080, backend reachable at http://localhost:8080/api/* via nginx proxy (same-origin, no CORS).

Seed problems on first run:

docker exec -i smc-postgres psql -U admin -d smcdb < backend/db/test_data.sql

Make targets

Command	What it does
make smc-up	Build images, start the stack, probe /api/healthz.
make smc-down	Stop the stack. Keeps the smc-postgres-data volume.
make smc-restart	smc-down then smc-up. Use after editing a Dockerfile or source.
make logs SERVICE=backend	Tail one service's logs (omit SERVICE= for all).
make ps	Show container status.
make healthz	Curl localhost:8080/api/healthz with 5 retries.
make help	List every target with one-line descriptions.

Wipe the database (named volume):

make smc-down
docker compose --env-file backend/.env -f docker-compose.yaml down -v
make smc-up

Deploy targets

The make deploy* targets pull prebuilt images from Docker Hub and run them via .deploy/dev/. They are intended for the host that fronts the public domain, not for laptops. Local dev uses make smc-up exclusively.

Command	What it does
make deploy	Pull lovetsmc/{frontend,backend}:dev, recreate any service whose image changed.
make deploy-frontend	Same, but only the frontend.
make deploy-backend	Same, but only the backend.
make deploy-down	Stop the deployed stack.

Repository layout

SMC/
├── frontend/          # Vite + React SPA (nginx on :8080)
├── backend/           # Go REST API + judge engine (:8081)
│   ├── internal/judge/   # Runner interface, ProcessRunner, DockerRunner
│   ├── db/               # PostgreSQL schema + seed data
│   └── ...
└── docker-compose.yaml   # Full stack: postgres + backend + frontend

Ports

Rule of thumb. Frontend uses the 8xxx range (currently just 8080). Everything in the Temporal / CD-service family uses the 7xxx range to stay visually distinct and avoid collisions. Where possible, host port equals container port so there is no host/container confusion when reading logs or config.

Service	Container port	Host port	Source compose
smc-postgres	5432	5432	root docker-compose.yaml
smc-backend	8081	8081	root docker-compose.yaml
smc-frontend	80	8080	root docker-compose.yaml
Vite dev server (local only)	5173	5173	npm run dev
Temporal server (gRPC)	7233	7233	infra/deploy/docker-compose.temporal.yaml
Temporal UI	7080	7080	infra/deploy/docker-compose.temporal.yaml
Temporal Postgres	5432	(unpublished)	infra/deploy/docker-compose.temporal.yaml
Elasticsearch (Temporal visibility)	9200	(unpublished)	infra/deploy/docker-compose.temporal.yaml
CD-service API	7082	7082	infra/deploy/docker-compose.yaml
CD-service Worker	—	—	infra/deploy/docker-compose.yaml

Quick host-port reference:

• 5173 — Vite dev server (frontend, local dev only)
• 5432 — PostgreSQL (SMC app database)
• 7080 — Temporal UI (http://localhost:7080)
• 7082 — CD-service webhook API
• 7233 — Temporal gRPC
• 8080 — SMC frontend (http://localhost:8080)
• 8081 — SMC backend API (http://localhost:8081/api)

Frontend

A single-page Vite + React 18 + TypeScript app built around @monaco-editor/react. Supports Python, JavaScript, and Go; dark / light theme toggle; per-language Monaco models so each language keeps its own buffer and undo stack. Connects to the backend API to submit code and display judge results. Served by nginx:1.27-alpine from a multi-stage Docker build on port 8080. For fast local iteration run npm run dev (Vite dev server on http://localhost:5173).

See frontend/README.md for setup, dev commands, and file layout.

Backend

A Go 1.24 REST API (backend/) that serves problems and judges code submissions against PostgreSQL-backed test cases. The judge uses a pluggable Runner interface with two backends:

• ProcessRunner — direct subprocess per language (dev only, no isolation)
• DockerRunner — one isolated container per test case (--network none, --memory 256m, --read-only); selected via JUDGE_BACKEND=docker

Results (Accepted / Wrong Answer / TLE / MLE / Runtime Error / Compile Error) are written back asynchronously; the frontend polls until a terminal status appears.

Port: 8081. See backend/README.md for the full API reference, judge design, sandbox flags, and run instructions.

sqlc-verify Guard

The backend CI runs an sqlc-verify stage as a drift guard: it runs sqlc generate from scratch and diffs the result against the committed internal/db/*.go. If anyone edits schema.sql or queries/*.sql without re-running sqlc generate locally and committing the regenerated internal/db/*.go, this check fails and blocks the PR.

To fix:

cd backend/
docker run --rm -v "$(pwd):/src" -w /src sqlc/sqlc generate

then commit the updated internal/db/ files.