Development-environment resolution engine that predicts failures before they happen, determines root causes with verifiable evidence, and proves environment invariants.
Modern development setups fail because code does not run in isolation—it depends on runtimes, system libraries, listening ports, background services, environment variables, and OS capabilities.
Conventional "doctor" commands merely test if a command exists in PATH.
CONCORD models your project and machine as a constraint graph to answer:
Why will this project fail on this machine, what chain of dependencies causes the failure, and can we prove it before running?
Zero AI required. CONCORD is 100% deterministic systems software written in Rust.
Install the latest release with one command (no Rust, Cargo, Node, or Docker required):
curl -fsSL https://raw.githubusercontent.com/axonel/concord/main/install.sh | shThe installer verifies SHA256 checksums automatically and places concord in ~/.local/bin.
To install a specific version or custom directory:
curl -fsSL https://raw.githubusercontent.com/axonel/concord/main/install.sh | CONCORD_VERSION=v0.2.1 shconcord .CONCORD — Development Environment Engine
──────────────────────────────────────────
Project: .
Name: my-backend
Languages: python
Environment: COMPATIBLE
✓ Project requirements discovered
✓ Runtime versions compatible
✓ Required services available
✓ Declared ports available
✓ Configuration consistent
No known blockers.
CONCORD — Development Environment Engine
──────────────────────────────────────────
Project: tests/fixtures/broken-python-version
Name: broken-python-version
Languages: python
2 problems detected (2 predicted failures)
HIGH python runtime incompatibility predicted
Project expects python >=3.99.0, but Runtime 'python' version 3.12.4 does not satisfy requirement >=3.99.0. Application startup or build is predicted to fail.
HIGH Required service 'postgresql' failure predicted
Project depends on service 'postgresql', but it is not running or not installed. Connections will be refused.
Next steps:
concord explain Inspect root causes and causal dependency chains
concord verify Run read-only environment verification checks
concord explainTraces the dependency graph back to the earliest violated invariant with exact machine provenance:
CONCORD — Development Environment Engine
──────────────────────────────────────────
Root-Cause Diagnosis & Causal Chains
1. python runtime incompatibility predicted
Root Cause: python.version >= >=3.99.0
Violated Constraint: Runtime 'python' must satisfy >=3.99.0
Confidence: HIGH
Affected Components: python, build, startup
Causal Chain:
├─► Host machine state: Runtime 'python' is installed at /usr/bin/python3 (version 3.12.4)
├─► Project specification: requires python >=3.99.0
├─► Violated invariant: python.version satisfies >=3.99.0
└─► Downstream impact: python toolchain cannot initialize; build and runtime will fail
2. Required service 'postgresql' failure predicted
Root Cause: service.postgresql.running
Violated Constraint: Service 'postgresql' must be running
Confidence: HIGH
Affected Components: postgresql, database/backend
Causal Chain:
├─► Host service state: Service 'postgresql' status is Stopped
├─► Project specification: depends on active service postgresql
├─► Violated invariant: service.postgresql.status == RUNNING
└─► Downstream impact: application connections to postgresql will be refused
Verify all requirements, ports, and services non-destructively:
concord verifyCONCORD — Development Environment Engine
──────────────────────────────────────────
Read-Only Environment Verification
✓ [PASSED] project_discovery Discovered 2 requirements and 0 declared ports across ["python"]
✗ [FAILED] runtime:python Runtime 'python' version 3.12.4 does not satisfy requirement >=3.99.0
✗ [FAILED] service:postgresql Service 'postgresql' is present but currently stopped/inactive
Summary: 1/3 checks passed (2 failed)
Environment verification FAILED.
Every command supports --json for CI/CD pipelines, pre-commit hooks, and developer tooling:
concord . --json{
"project": {
"name": "broken-python-version",
"root_path": "/workspace/broken-python-version",
"languages": ["python"],
"package_managers": [],
"requirements": [...],
"declared_ports": [],
"env_vars": [],
"docker_used": false,
"evidence": [...]
},
"machine": {
"os": "Ubuntu 24.04 LTS",
"arch": "x86_64",
"cpu_count": 8,
"runtimes": [...],
"services": [...],
"listening_ports": [...]
},
"evaluated_constraints": [...],
"predictions": [
{
"title": "python runtime incompatibility predicted",
"category": "runtime_incompatibility",
"summary": "Project expects python >=3.99.0, but Runtime 'python' version 3.12.4 does not satisfy requirement >=3.99.0.",
"confidence": "HIGH",
"affected_components": ["python", "build", "startup"]
}
],
"diagnoses": [...],
"verification": {
"success": false,
"checks": [...],
"total_checks": 3,
"passed_checks": 1,
"failed_checks": 2
}
}| Category | Supported Technologies |
|---|---|
| Host OS | Linux (Ubuntu, Debian, Fedora, Arch, Alpine, etc.) on x86_64 |
| Languages & Runtimes | Node.js, Bun, Python, Rust, Go, Java |
| Package Managers | npm, pnpm, yarn, bun, uv, poetry, pipenv, cargo |
| Containers & Services | Docker (daemon socket, live containers docker ps -a, compose projects), PostgreSQL, Redis |
| Project Signals | package.json, bun.lock, pyproject.toml, requirements.txt, uv.lock, Dockerfile, docker-compose.yml, compose.yaml, .nvmrc, .python-version, .tool-versions, mise.toml, Cargo.toml, go.mod, .env.example |
If you prefer to download release binaries directly from GitHub Releases:
-
Download the archive and SHA256 checksum:
curl -LO https://github.com/axonel/concord/releases/download/v0.2.1/concord-v0.2.1-linux-x86_64.tar.gz curl -LO https://github.com/axonel/concord/releases/download/v0.2.1/concord-v0.2.1-linux-x86_64.tar.gz.sha256
-
Verify the checksum:
sha256sum -c concord-v0.2.1-linux-x86_64.tar.gz.sha256
-
Extract and move to your PATH:
tar -xzf concord-v0.2.1-linux-x86_64.tar.gz mkdir -p ~/.local/bin mv concord-v0.2.1-linux-x86_64/concord ~/.local/bin/
git clone https://github.com/axonel/concord.git
cd concord
cargo build --release
./target/release/concord --versionSee ARCHITECTURE.md for details on:
- The 8-stage deterministic resolution pipeline
- Environment IR and Evidence provenance model
- Data-driven constraint evaluation
- Graph traversal and causal chain tracing
- Planned roadmap (Minimal Repair Planner, Counterfactual Simulation, Transactional Execution)