Can't use 'deploy' with the container-based infrastructure

[orome]

When I use the Travis CI "container-based" infrastructure, I must have

sudo: false

set in my .travis.yml; but this appears to be incompatible with automatic deployment using, for example

deploy:
  provider: hackage

which causes my build to fail with

Installing deploy dependencies
sudo: must be setuid root

How can I use automatic deployment from Travis CI with the container-based infrastructure?

[orome]

The offending .travis.yml:

# Use new container infrastructure to enable caching
sudo: false

# Choose a lightweight base image; we provide our own build tools.
language: c

# GHC depends on GMP. You can add other dependencies here as well.
addons:
  apt:
    packages:
    - libgmp-dev

# The different configurations we want to test. You could also do things like
# change flags or use --stack-yaml to point to a different file.
env:
- ARGS="--resolver lts-3.7"
- ARGS="--resolver nightly"
#- ARGS=""

before_install:
# Download and unpack the stack executable
- mkdir -p ~/.local/bin
- export PATH=$HOME/.local/bin:$PATH
- travis_retry curl -L https://github.com/commercialhaskell/stack/releases/download/v0.1.4.0/stack-0.1.4.0-x86_64-linux.tar.gz | tar xz -C ~/.local/bin

# This line does all of the work: installs GHC if necessary, build the library,
# executables, and test suites, and runs the test suites. --no-terminal works
# around some quirks in Travis's terminal implementation.
script: stack $ARGS --no-terminal --install-ghc test --haddock

# Caching so the next build will be fast too.
cache:
  directories:
  - "$HOME/.stack"

# Deploy (tagged commits) to Hackage; generated by travis CLI
before_deploy: "echo '=== BEGIN deployment ==='"
deploy:
  provider: hackage
  username: Orome
  password:
    secure: #...
  on:
    repo: orome/crypto-enigma-hs
    branch: hackage
    tags: true
after_deploy: "echo '=== END deployment ==='"

[BanzaiMan]

hackage provider depends on cabal, which requires sudo, so you can't use it on containers.

Please use the legacy infrastructure, or Trusty.

[orome]

@BanzaiMan — When I switch to legacy infrastructure, I get

Installing deploy dependencies
E: Unable to locate package cabal

Can you help quickly point out what I'm missing and need to do to fix that?