Skip to main content

Perl on Miren

Perl isn't auto-detected, so you deploy it with a Dockerfile.miren. This guide uses Mojolicious, which ships its own production web server — no separate PSGI wiring needed. The same pattern works for Dancer2 or any PSGI app run under Plack.

Let your agent do this

Ask your AI coding agent to "set up this Perl app on Miren" after installing the Miren agent skills. It adds the Dockerfile.miren, points the server at 0.0.0.0:$PORT, and deploys — using this page as its reference.

Does this source build need a Dockerfile?​

Yes. Miren doesn't auto-detect Perl, so add a Dockerfile.miren to your project root. Miren builds from it instead of guessing the stack — see Using Dockerfile.miren.

Want native support?

Miren auto-detects and builds common stacks (Python, Node, Bun, Go, Ruby, Rust) without a Dockerfile. This language isn't one of them yet — if you'd like first-class support, request it.

Bind to the injected port​

Miren injects PORT and routes traffic to it. Mojolicious's daemon command takes a listen URL — use http://*:$PORT to bind all interfaces:

use Mojolicious::Lite -signatures;

get '/' => sub ($c) {
  $c->render(text => "Hello from Perl on Miren!\n");
};

app->start;

The Dockerfile​

Create Dockerfile.miren in your project root. Install dependencies with cpanm:

FROM perl:5.40

WORKDIR /app
RUN cpanm --notest Mojolicious
COPY . /app

EXPOSE 8080
CMD ["sh", "-c", "exec perl /app/app.pl daemon -l \"http://*:$PORT\""]

For an app with a cpanfile, install from it instead: RUN cpanm --notest --installdeps .

.dockerignore​

.git

Deploy​

The Dockerfile's CMD starts the app. Miren uses it as the web service's startup default, so you don't need a Procfile or service command.

Create .miren/app.toml naming your app and deploy from your project root:

name = "perl-bench"
miren deploy

For a PSGI app (Dancer2, Catalyst), install Plack and Starman in the Dockerfile:

RUN cpanm --notest Plack Starman

Then replace the Dockerfile's CMD with one that starts the PSGI app:

CMD ["sh", "-c", "exec plackup -s Starman --host 0.0.0.0 --port \"$PORT\" /app/app.psgi"]

Environment variables​

Set variables with miren env set — -e for plain values, -s for secrets (masked in output and logs). Read them with $ENV{KEY}:

miren env set -e MOJO_MODE=production
miren env set -s DATABASE_URL

You can also declare variables in .miren/app.toml:

[[env]]
key = "DATABASE_URL"
value = ""
required = true
sensitive = true

See App Configuration — Environment Variables.

Agent quick reference​

  • Detection: none — requires Dockerfile.miren
  • Base image: perl:5.40; cpanm --notest Mojolicious (or --installdeps . with a cpanfile)
  • Startup: inherited from the Dockerfile CMD; no Procfile or service command needed
  • Port: Mojolicious daemon -l http://*:$PORT; PSGI apps use plackup --host 0.0.0.0 --port $PORT
  • Env vars: miren env set -e/-s; read with $ENV{KEY}

Next steps​