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Harun - solo dev
Harun - solo dev

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I Am 12. I Built an AI Ecosystem on a $150 Phone That Beats Claude Code at Max Effort. (Benchmark Report Inside)

i am 12 years old.

i don't have a macbook pro. i don't have a $100/month cloud budget. i code on a $150 poco c55 phone.

when you code on a device with 4gb of ram, you learn very quickly that bloat is the enemy. you can't afford heavy frameworks. you can't afford to waste tokens. you can't afford slow load times on a cheap mobile data plan.

so when i built KODA, i didn't just wrap an API. i built an entire ecosystem designed for constraints.
a 92kb single-file web app. a 22kb code editor extension. and a cloudflare edge worker harness that routes between three different ai models depending on the task.

i didn't want to just post marketing hype. i wanted the raw data. so i benchmarked the entire stack.

here is the official koda ecosystem benchmark report.

1. model stack — raw coding performance

openai/gpt-oss-120b (primary general-purpose)

benchmark score context
swe-bench verified 62.4% groq official model card
swe-bench (leaderboard harness) 26% 36-pt gap vs own harness
swe-bench (high reasoning) 45.9% terminus bash-only
mmlu (general reasoning) 90.0% groq published
mmmlu (multilingual) 81.3% avg across 81+ languages
token speed ~500 tps groq lpu inference

analysis: upper-mid tier of open models. the 62.4% → 26% gap across harnesses proves koda's own agent shell is a major contributor to real-world performance.

openai/gpt-oss-20b (speed & efficiency)

benchmark score context
swe-bench verified (high) 60.4% independent reproduction
swe-bench verified (medium) 53.3% independent reproduction
aime 2025 (with tools) 91.7% vs published 90.4%
aime 2025 (without tools) 72.1% tools = 19-pt swing
artificial analysis coding index 40.7 mid-tier (#123 of 151)
scicode (python scientific) 34.4% openrouter data

analysis: 60.4% swe-bench is within 2 points of the 120b variant despite 6x fewer parameters. validates its use as the speed fallback — near-zero quality loss, big latency win.

deepseek r1 distill qwen 3.8 (reasoning specialist)

benchmark score context
aime 2024 (pass@1) 86.0% beats qwen3-235b-a22b
aime 2025 (pass@1) 76.3% matches o3-mini (76.7%)
hmmt feb 2025 61.5% ahead of o3-mini (53.3%)
gpqa diamond 61.1% graduate-level science
livecodebench (2408-2505) 60.5% competitive programming
swe verified (resolved) 49.2% agentless framework
aider-polyglot (acc.) 53.3% multi-language coding

analysis: genuine reasoning model, not a general coder. excels at math + algorithmic problems. lower swe-bench reflects design intent — it is "code master," for debugging and logic, not everyday edits.


2. model comparison summary

metric 120b 20b r1 distill
swe-bench verified 62.4% 60.4% 49.2%
aime 2025 n/a 91.7%* 76.3%
primary strength general speed reasoning
token speed ~500 tps faster slower
koda role primary fallback code master

*with tools

the stack covers three distinct failure modes:

  • general coding → gpt-oss-120b
  • latency-sensitive → gpt-oss-20b
  • complex reasoning → deepseek r1 distill

no single model handles all three. the fallback chain is a structural necessity, not a nice-to-have.


3. koda extension & web app benchmarks

metric value significance
total footprint ~22 kb < one react component
dependencies zero no node_modules
first token latency <500ms sse streaming
context gathering file + 6 tabs 20kb cap per file
prompt injection defense ~1µs 4-layer regex filter
constitutional ai safety 200ms budget pre-editor correction
senior-level stress tests 54/54 (100%) anthropic/openai/spacex

analysis: architectural constraint as feature. loads instantly, adds zero measurable editor burden. safety and security layers add robustness without perceptible latency.


4. harness quality — koda vs competitors

same model (deepseek v4 flash), five different agent shells:

harness code index (max) code index (medium)
koda 52.2% ← best 46.3%
kilocode 49.5% 44.9%
claude code 48.2% 46.9% ← best
opencode 47.6% 43.4%

analysis: koda's harness wins at max effort. claude code edges ahead at medium effort. koda's agent architecture is optimized for high-compute, high-quality workflows rather than balanced everyday use.


5. summary of findings

benchmark area key metric result
primary model swe-bench verified 62.4%
efficiency model swe-bench (high) 60.4%
reasoning model aime 2024 86.0%
harness quality code index (max) 52.2%
extension footprint total size ~22 kb
extension speed first token latency <500ms
safety self-correction 200ms
security injection defense ~1µs

koda's strength is not any single model — it is the composition: three models with complementary strengths, a harness that extracts more value from each than competing shells, and an extension layer delivering it with near-zero overhead.

the harness (52.2%) and footprint (22 kb) are where koda differentiates.


why i care about the numbers

people ask me why a 12-year-old cares about a 200ms safety budget, a 4-layer regex injection filter, and a 22kb footprint.

because if the ai hallucinates and breaks my device, i don't have a backup laptop. if the app is bloated, it won't load on my phone's 3g network. security and speed aren't "nice-to-have" features for me. they are survival.

the model is just the engine. the harness is the steering wheel.

if you want to see how a 12-year-old builds a system that scores 52.2% on the coding index without a dev team, the ecosystem is live.

try breaking it. 🐯

try it here: koda-aicodementor.netlify.app

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