Installation

Prerequisites: Rust and Cargo

ripopt is written in Rust. Install the Rust toolchain via rustup:

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
source "$HOME/.cargo/env"

Verify: rustc --version && cargo --version

Install ripopt

git clone https://github.com/jkitchin/ripopt.git
cd ripopt
make install

This builds the release binary and shared library, then installs:

• ripopt AMPL solver binary → ~/.cargo/bin/
• libripopt.dylib / libripopt.so → ~/.local/lib/

Verify: ripopt --version

Using ripopt as a Rust library

Add to your Cargo.toml:

[dependencies]
ripopt = { git = "https://github.com/jkitchin/ripopt" }

Using ripopt with Python/Pyomo

pip install ./pyomo-ripopt

from pyomo.environ import *
solver = SolverFactory('ripopt')
result = solver.solve(model, tee=True)

Using ripopt with Julia/JuMP

cargo build --release
julia -e 'import Pkg; Pkg.develop(path="Ripopt.jl")'

ENV["RIPOPT_LIBRARY_PATH"] = "/path/to/ripopt/target/release"
using JuMP, Ripopt

model = Model(Ripopt.Optimizer)
@variable(model, 1 <= x[1:4] <= 5)
set_start_value.(x, [1.0, 5.0, 5.0, 1.0])
@NLobjective(model, Min, x[1]*x[4]*(x[1]+x[2]+x[3]) + x[3])
@NLconstraint(model, x[1]*x[2]*x[3]*x[4] >= 25)
@NLconstraint(model, x[1]^2 + x[2]^2 + x[3]^2 + x[4]^2 == 40)
optimize!(model)
println(objective_value(model))  # ≈ 17.014

Using ripopt with GAMS

cargo build --release
make -C gams && sudo make -C gams install

option nlp = ripopt;
Solve mymodel using nlp minimizing obj;

Options via ripopt.opt (same format as Ipopt):

tol 1e-8
max_iter 1000
print_level 5

Using the C API

After make install, link against the shared library using ripopt.h:

cc my_program.c -I/path/to/ripopt -L~/.local/lib -lripopt -lm

Uninstall

make uninstall