Shared host — limitations

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A shared host gives you PHP, FTP/SSH, and a public_html-style document root. It does not give you root, systemd, Docker, or a way to run long-lived processes. Spora is designed to degrade gracefully under these constraints, but some features are restricted.

Mercure SSE → falls back to polling

Spora publishes task state changes to a Mercure hub for real-time UI updates (no polling). The docker/frankenphp.conf in the canonical Docker image runs Mercure natively on FrankenPHP.

On a shared host, you don’t have FrankenPHP or a way to run Mercure. The orchestrator detects this and falls back to polling. Specifically:

  • The MercurePublisher::publish() method early-returns false (logged at debug level) when the SPORA_MERCURE_URL env var is not set
  • The frontend falls back to polling /api/v1/tasks/{id} for state changes

What you lose: task state changes appear in the UI after the polling interval (default 5 s), not instantly. For most users this is invisible; for power users with many concurrent agents, it adds latency.

What to do: if your host offers a managed Mercure service, set SPORA_MERCURE_URL + SPORA_MERCURE_JWT_KEY and the publisher activates automatically. If not, ignore — the polling fallback works.

Worker daemon mode → use cron

php bin/spora worker:run --daemon requires a long-lived process. Most shared hosts don’t let you run daemons (no nohup, no systemd, the host kills background processes when your shell disconnects).

The fallback is worker:run --once --include-queue from cron:

* * * * * cd /home/user/my-spora && /usr/bin/php bin/spora worker:run --once --include-queue >> storage/spora.log 2>&1

What you lose: if a task takes longer than 60 s, the next cron fire will start a second worker process while the first is still running. The lockForUpdate() row lock in the claim transaction prevents double-processing, but you burn 2× CPU and make 2× LLM API calls.

What to do: for tasks that regularly exceed 60 s, move to Classical server and run the daemon properly. Otherwise, the cron fallback works fine for small workloads.

HTTPS termination → the host’s responsibility

Spora’s Docker image includes a FrankenPHP Caddyfile that can do TLS via ACME (Let’s Encrypt). On a shared host, you don’t control the web server — the host terminates TLS, usually via:

  • cPanel AutoSSL (Let’s Encrypt, automatic renewal)
  • Plesk SSL (same)
  • Cloudflare proxy (if you put the host behind Cloudflare)

Spora’s SPORA_APP_URL env var should match the public HTTPS URL so verification emails, password-reset links, and CSRF checks use the right origin. If the host uses a proxy that changes the host header, configure that on the host’s reverse proxy.

No Docker

If you need to deploy a custom build of Spora (your own fork, additional extensions, custom branding), the shared host path doesn’t work. You need:

Filesystem limitations

Most shared hosts have per-user disk quotas (1-50 GB). Spora’s storage footprint is small by default:

  • SQLite DB: grows with conversations, agents, and plugin data — typically 1-100 MB
  • Secret key: 32 bytes (one-time)
  • Logs: 1-10 MB/day at moderate traffic
  • Frontend assets: 5-10 MB (prebuilt, static)

If you have many plugins with high LLM traffic, logs can grow. Set up log rotation via the host’s control panel (most cPanels have a “log rotation” tool) or use logrotate if you have cron access.

PHP extensions

The Spora composer.json requires:

  • php: ^8.4
  • ext-pdo_mysql (required, even for SQLite runtime)
  • ext-json (always present in PHP 8+)
  • ext-mbstring (usually present)
  • ext-zip (required by Composer, usually present)

Most shared hosts have all of these. If composer install fails with a platform error, ask the host to enable the missing extension.

proc_open may be disabled

composer install and the plugin install CLI shell out to git, composer, and similar. If the host has disable_functions = proc_open in php.ini, the install command will fail. There’s no workaround at the application level — you need to ask the host to enable proc_open, or use a host that doesn’t disable it.

Resource limits

Shared hosts typically cap:

  • PHP memory_limit: 128-512 MB. Spora needs at least 256 MB for large LLM responses. Adjust in cPanel’s “MultiPHP INI Editor” if needed.
  • Max execution time: 30-120 s. Long agent loops can hit this. Adjust in cPanel’s “MultiPHP INI Editor” or via .user.ini.
  • Concurrent connections: 10-50. Spora’s FrankenPHP runtime is efficient but a long task per request will block others.

If your workload outgrows these, the path forward is a VPS.

What IS supported

  • ✓ bin/spora CLI commands (install, plugin install/uninstall, db:reset, db:seed, spora:install)
  • ✓ Composer-managed dependencies
  • ✓ SQLite runtime (no external service)
  • ✓ MySQL runtime (if the host offers MySQL)
  • ✓ Background tasks via cron + --once --include-queue
  • ✓ Cron-triggered scheduled agent runs
  • ✓ HTTPS via the host’s TLS termination
  • ✓ Backups via tar of the storage/ directory + .env
  • ✓ Per-tool encrypted credentials (SPORA_SECRET_KEY + ToolConfigService)

What is NOT supported

  • ✗ Long-lived worker daemon (use cron instead)
  • ✗ Native Mercure SSE (falls back to polling)
  • ✗ Docker / container builds (use a VPS or PaaS)
  • ✗ Custom system services (no systemd on shared hosts)
  • ✗ Server-pushed real-time updates (long-lived connections usually blocked)
  • ✗ Loading custom PHP extensions (no root)
  • ✗ Running Composer in production if proc_open is disabled

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