# Gemini 3.6 Flash on iac-bench 2026-10

> Source: <https://www.massdriver.cloud/blogs/iac-bench-2026-10-gemini-3-6-flash>
> Published: 2026-11-04 00:00:00+00:00

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How Gemini 3.6 Flash did on iac-bench 2026-10: an overall composite of 54.3, scores per fixture, strengths, weaknesses and the patterns in its OpenTofu modules.

| Developer |  | 
| API identifier | `gemini-3.6-flash` | 
| Access | Gemini API | 
| Weights | Closed | 
| List price (USD / M tokens, in / out) | 0.75 / 3.75 (OpenRouter, 2026-10-23) | 
| Evaluated | 2026-10-22 (generation) · 2026-10-23 (judge) | 
| Attempts | 9 (3 fixtures × 3 samples) | 
| **Overall composite** | **54.3** (95% CI 40.0–61.5) | 
| Rank | 10 of 10 (95% rank interval 10–10) | 
| Mechanical only / judge only | 50.9 (rank 10) / 62.3 (rank 10) | 
| Failed gates · insecure attempts | 1/9 · 8/9 | 
| Estimated cost, all 9 attempts | $3.14 | 

Gemini 3.6 Flash places last, with security findings in 8 of 9 attempts and one failed
gate. Its defining habit is to ship secure values as *defaults on consumer-facing inputs*
rather than as fixed properties. The S3 public access block, Cloud SQL public IP and
`ssl_mode`, and App Service HTTPS are all inputs, each with a safe default and no
validation.

That one habit drives most of its losses:

`H1` lost in every attempt that planned (8/8);
Its resource mechanics, by contrast, are consistently sound.

| Fixture | Composite median (range) | Rubric median | Expertise | Judge median | ✗ gate | ⚠ security | Median inputs | Median output tokens | Median time | Median cost | 
|---|---|---|---|---|---|---|---|---|---|---|
| G001 · S3 | 62.8 (55.9–65.1) | 0.581 | 4/7 | 73.7 | 0/3 | 3/3 ( `H1` ) | 22 | 18,077 | 235 s | $0.164 | 
| G002 · Cloud SQL | 49.2 (48.2–59.2) | 0.454 | 6/9 | 55.3 | 0/3 | 3/3 ( `H1` ,`H2` ) | 33 | 28,188 | 238 s | $0.297 | 
| G003 · App Service | 51.0 (15.0–62.4) | 0.472 | 3/5 | 57.9 | 1/3 | 2/3 ( `H1` ,`H2` ) | 40 | 51,324 | 666 s | $0.473 | 

Rubric items not at full credit, counted over attempts that planned: G001: `A3` 3/3, `A5` 3/3, `B1` 1/3, `H1` 3/3, `H9` 1/3, `H12` 3/3, `H13` 3/3, `H15` 2/3; G002: `A8` 3/3, `B1` 2/3, `H1` 3/3, `H2` 3/3, `H4` 1/3, `H5` 1/3, `H7` 3/3, `H9` 3/3, `H10` 3/3, `H11` 3/3; G003: `A6` 2/2, `A7` 2/2, `H1` 2/2, `H2` 2/2, `H3` 1/2, `H4` 1/2, 1 attempt failed the gate. Definitions are in [Scoring criteria](https://www.massdriver.cloud/blogs/iac-bench-2026-10-scoring-criteria).

`H2`, 3/3.` ipv4_enabled` is an input.`ssl_mode` is an unvalidated string, and its own description lists the unencrypted mode
(excerpt below).`database_flags` turn IAM authentication off.`https_only` is missing on the
slot or exposed as an input, and the basic-auth publishing flags are never set.`H7`, `H10`, 3/3).` validation` blocks across all nine modules.`test*.tf` files.
`G002/gemini-3.6-flash-e1/variables.tf` lines 65–75

```
variable "ipv4_enabled" {
  description = "Whether public IPv4 is assigned to the instance. Default is false (Private IP only)."
  type        = bool
  default     = false
}

variable "ssl_mode" {
  description = "SSL/TLS connection mode: ENCRYPTED_ONLY, TRUSTED_CLIENT_CERTIFICATE_REQUIRED, or ALLOW_UNENCRYPTED_AND_ENCRYPTED."
  type        = string
  default     = "ENCRYPTED_ONLY"
}
```

Both defaults are secure, but each control is an unvalidated consumer input, and the description advertises the unencrypted mode. This fails both mandatory Cloud SQL items.

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