kleisli.io

Correctness infrastructure for the agentic era.

Built and operated for teams shipping agent-generated code.

The verification layer is missing. Agents generate code faster than any human process can check it. The bottleneck is not skill. It is architecture. Kleisli.IO is the practice that builds the missing layers.

The architecture.

  1. 06reasoning
  2. 05coordination→ cairn
  3. 04agency→ kli
  4. 03machines
  5. 01verification→ nix-effects

layers 01–02, in production

metaBuilder/examples/idl/builder.nix$ nix eval github:kleisli-io/metaBuilder#examples.idl.validation
  idl = mb.ornaments.idl;

  spec = idl.fromProtobuf {
    name = "example-idl";
    protos = [ ./schema.proto ];
    languages = [ "cpp" "java" ];
  };

  program = mb.program.fromOrnamentedSpec
    idl.IdlBuilder.T spec;
{ diagnostics = [ ]; ok = true; }

Live output. Every view above is the same spec, interpreted at nix eval time, before anything builds.

in production

Kleisli.IO operates the complete technical infrastructure for the Lie-Størmer Center, Norway's national center for mathematics.

Built on the Kleisli stack. Operated from Tromsø.

Lie-Størmer-senteretUiT The Arctic University of NorwayAMTI

Going deeper.

metaBuilderJune 2026

An Experiment in Heterogeneous Software Builds

An experiment report on metaBuilder, a typed builder DSL we built to test whether ornaments are what relate heterogeneous build descriptions, and what held under test once we did.

nixFebruary 2026

Dependent Types in Pure Nix

nix-effects embeds a Martin-Löf Type Theory proof checker in pure Nix. Dependent functions, dependent pairs, identity types with J, cumulative universes, verified extraction of plain Nix functions from proof terms. The whole system runs at nix eval time.

nixFebruary 2026

Trampolining Nix with genericClosure

Nix has no loops and no tail-call optimization. builtins.genericClosure, the package dependency primitive, doubles as a general-purpose trampoline once you break the thunk chain.

Agents write code.
Your team needs to know it is correct.