FractalvsPywen
Generated from the two spec rows. Green marks the better value where a spec has a clear direction. Everything else is just different.
Fractal
Trampoline AI · Terminal agent
#224OSS
Panel
4.62 spec wins
- Reliability
- 3.7
- Usefulness
- 4.2
- Cost
- 6.0
- Longevity
- 4.7
“The runtime is described as self-harnessed, which is a very confident way to say the loop calls itself.”
Pywen
PAMPAS Lab · Terminal agent
#261OSS
Panel
4.70 spec wins
- Reliability
- 4.3
- Usefulness
- 4.2
- Cost
- 6.7
- Longevity
- 3.5
“Its bundled agent ships a todowrite tool, so it can now record in writing the things it will not be getting to.”
Spec by spec
| Spec | Fractal | Pywen |
|---|---|---|
| Architecture | ||
| Category | Terminal agent | Terminal agent |
| Runs | local | local |
| Platforms | macos | macos, linux |
| Context window | not documented | not documented |
| Protocols | ||
| MCP client | No | No |
| MCP server | No | No |
| Capabilities | ||
| Runs terminal commands | Yes | Yes |
| Multi-file edits | Yes | Yes |
| Git operations | No | No |
| Browser control | No | No |
| Sandboxed execution | Yes | No |
| Multi-agent orchestration | Yes | Yes |
| Headless / CI mode | No | No |
| Models | ||
| Backbone | predict-rlm | Qwen, Claude |
| Bring your own model | Yes | Yes |
| Local models | No | No |
| Cost | ||
| Pricing model | byok | byok |
| Starts at | $0/mo | $0/mo |
| Free tier | Yes | Yes |
| Bring your own key | Yes | Yes |
| Openness | ||
| Open source | Yes | Yes |
| License | MIT | MIT |
| GitHub stars | 200 | 109 |
Which one would each critic pick
| Critic | Fractal | Pywen | Pick |
|---|---|---|---|
| El Juez | — | — | not enough reviews |
| El Amigo | 4.5 | 4.8 | Pywen — Pick this if your job is comparing coding agents; pick almost anything else on this board if your job is writing software with one. |
| El Crítico | 4.3 | 4.3 | no preference |
| El Profesor | 5.3 | 5.0 | Fractal — The agent is structured as a recursive language model rather than a flat loop, so decomposition is the control flow instead of a prompt convention. |
| La Inversora | 4.8 | 4.5 | Fractal — 200 stars and seventy-three public mentions in a year, from a named company, which is more attention than most projects here and more than the software has earned. |
| La Jefa | 3.5 | 4.5 | Pywen — Free across sixty seats, and it is the rare row that names permission control, an approval flow and a trajectory audit as first-class rather than as a roadmap item. |
| El Hacker | 5.5 | 5.0 | Fractal — MIT and my own key, installed by a script next to uv, which is fine; the weights still have to live somewhere other than my machine. |
Picks are derived from each critic's own scores. Humans vote on matchups on the duels page.